CN111826087B

CN111826087B - Water-based non-curing rubber asphalt waterproof coating and preparation method thereof

Info

Publication number: CN111826087B
Application number: CN201910313423.1A
Authority: CN
Inventors: 江宽; 刘双旺; 董大伟; 董进学; 武晋巍; 冯亚琴
Original assignee: Beijng Environmental Protection Technology Co ltd Wing Tai Luther
Current assignee: Beijng Environmental Protection Technology Co ltd Wing Tai Luther
Priority date: 2019-04-18
Filing date: 2019-04-18
Publication date: 2022-01-28
Anticipated expiration: 2039-04-18
Also published as: CN111826087A

Abstract

The invention provides a water-based non-cured rubber asphalt waterproof coating and a preparation method thereof. The coating comprises a component A and a component B, wherein the weight ratio of the component A to the component B is (20-40) to (2-10); the component A comprises emulsified modified asphalt and waste rubber emulsion, the waste rubber emulsion comprises linearized macromolecular rubber, a first emulsifier and water, wherein the linearized macromolecular rubber is obtained by sequentially carrying out desulfurization treatment and micromolecule removal on the waste rubber, and the molecular weight of the linearized macromolecular rubber is more than 10000; and the first emulsifier is a first anionic emulsifier; the component B is coagulant water solution. The water-based non-cured rubber asphalt waterproof coating does not contain volatile organic solvents, is good in environmental protection, and has good demulsification effect and strong adhesion. In addition, the raw material cost of the water-based non-cured waterproof coating can be greatly reduced by adopting the waste rubber emulsion.

Description

Water-based non-curing rubber asphalt waterproof coating and preparation method thereof

Technical Field

The invention relates to the technical field of non-cured waterproof coatings, and particularly relates to a water-based non-cured rubber asphalt waterproof coating and a preparation method thereof.

Background

Non-curable waterproof coatings are an important type of coating, and are generally classified into oil-based non-curable waterproof coatings and water-based non-curable waterproof coatings according to their solvent systems. At present, most of oily non-cured waterproof coatings need to be heated to more than 130 ℃ for secondary heating in construction to carry out spraying or brushing construction, are inconvenient to construct, easily cause the problem of environmental pollution, and are easy to scald workers. The water-based non-curing waterproof coating is favored by people because of construction at normal temperature, no need of heating, convenient construction, low equipment requirement and the like.

The invention discloses a water-based non-cured rubber asphalt coating and a preparation method thereof, and the water-based non-cured rubber asphalt coating is prepared by emulsifying modified rubber asphalt and mixed tackifying resin, and then adding a self-adhesive auxiliary agent, an interface auxiliary agent, an antifreezing agent and an anti-aging agent for compounding. The cationic emulsifier is adopted in the patent, and a proper quick-setting demulsifier is not adopted, so that the demulsification effect is influenced because the demulsification can not be separated out quickly, and the organic solvent is adopted, so that Volatile Organic Compounds (VOC) exist in the product, and the environment is not favorable.

The patent CN106398536 discloses an anionic rubber asphalt waterproof coating and a preparation method thereof, wherein the coating comprises 85-95 parts by mass of an anionic emulsion, 2-5 parts by mass of an anionic SBR latex, 4-7 parts by mass of an anionic neoprene latex, 0.1-1 part by mass of a hydrophobic agent and 0.5-2.5 parts by mass of an anti-seepage agent as a component A, and an inorganic salt solution is dissolved as a component B. The raw materials adopted by the method have higher price and higher cost.

In a word, the existing water-based non-cured waterproof coating has the problems of insufficient environmental protection, poor demulsification effect, high cost and the like.

Disclosure of Invention

The invention mainly aims to provide a water-based non-cured rubber asphalt waterproof coating and a preparation method thereof, and aims to solve the problem that the water-based non-cured rubber asphalt waterproof coating in the prior art cannot have the performances of environmental friendliness, demulsification effect, low cost and the like.

In order to achieve the above object, according to one aspect of the present invention, there is provided an aqueous non-curable rubberized asphalt waterproofing paint, comprising an a component and a B component, wherein the weight ratio of the a component to the B component is (20-40): 2-10; the component A comprises emulsified modified asphalt and waste rubber emulsion, the waste rubber emulsion comprises linearized macromolecular rubber, a first emulsifier and water, wherein the linearized macromolecular rubber is obtained by sequentially carrying out desulfurization treatment and micromolecule removal on the waste rubber, and the molecular weight of the linearized macromolecular rubber is more than 10000; and the first emulsifier is a first anionic emulsifier; the component B is coagulant water solution.

Further, the solid content of the waste rubber emulsion is 30-70%; preferably, the waste rubber emulsion comprises 40-70 parts by weight of the linearized macromolecular rubber, 0.3-10 parts by weight of the first emulsifier and 30-40 parts by weight of water.

Further, the weight ratio of the emulsified modified asphalt to the waste rubber emulsion is (60-80) to (20-40); the optimized emulsified modified asphalt comprises modified asphalt, an aqueous solution of a first reinforcing filler and a second emulsifier, wherein the second emulsifier is a second anionic emulsifier; preferably, the emulsified modified asphalt comprises 50-70 parts of modified asphalt, 29-47 parts of aqueous solution of a first reinforcing filler and 1-3 parts of a second emulsifier in parts by weight; more preferably, the modified asphalt comprises 100 parts by weight of base asphalt and 1-5 parts by weight of elastomer polymer.

Further, the matrix asphalt is 70-120 # petroleum asphalt, and the elastomer polymer is one or more of SBS, SBR and NR.

Further, the first anionic emulsifier and the second anionic emulsifier are respectively selected from one or more of carboxylate, sulfate, sulfonate and phosphate.

Further, the first reinforcing filler in the aqueous solution of the first reinforcing filler is one or more of nano-clay, kaolin, diatomite, bentonite, talcum powder and calcium powder; preferably, the solid content of the aqueous solution of the first reinforcing filler is 10-30%.

Further, the aqueous coagulant solution comprises an aqueous solution of a coagulant and a second reinforcing filler; preferably, the aqueous coagulant solution includes, by weight, 5 to 15 parts of the coagulant and 85 to 95 parts of the second reinforcing filler.

Further, the coagulant is selected from one or more of magnesium chloride, calcium chloride, aluminum sulfate, aluminum potassium sulfate, poly-phosphorus ferric chloride and poly-phosphorus aluminum chloride; preferably, the second reinforcing filler in the aqueous solution of the second reinforcing filler is one or more of nano clay, kaolin, diatomite, bentonite, talcum powder and calcium powder, and more preferably, the solid content of the aqueous solution of the first reinforcing filler is 10-30%.

According to another aspect of the present invention, there is also provided a method for preparing an aqueous non-curing rubber asphalt waterproof coating material, comprising the steps of: mixing and dispersing the emulsified modified asphalt and the waste rubber emulsion to obtain a component A; preparing a coagulant aqueous solution as component B; wherein the waste rubber emulsion is prepared by the following method: performing desulfurization degradation on the waste rubber to obtain linear active rubber; wherein the weight percentage content of the linearized molecules in the linearized active rubber is more than or equal to 75 percent; extracting linear macromolecular rubber with the molecular weight more than 10000 from the linear active rubber; mixing and emulsifying the linearized macromolecular rubber, the first emulsifier and water to obtain the waste rubber emulsion.

Further, the step of extracting the linearized macromolecular rubber comprises: mixing the linearized active rubber with a first solvent to dissolve small molecules with the molecular weight less than 10000 in the linearized active rubber to obtain a first mixture; carrying out first solid-liquid separation on the first mixture, and drying and precipitating to obtain a pre-separated substance; mixing the pre-separated substance with a second solvent to dissolve the linear macromolecular rubber with the molecular weight more than 10000 in the pre-separated substance to obtain a second mixture; carrying out second solid-liquid separation on the second mixture to obtain supernatant containing the linearized macromolecular rubber; in the process of mixing and emulsifying the linearized macromolecular rubber, the first emulsifier and water, adding the linearized macromolecular rubber in the form of supernatant, and removing a second solvent in the system after the emulsifying step to obtain waste rubber emulsion; preferably, the first solvent is one or more of acetone, ethanol, diethyl ether and isopropanol; preferably, the second solvent is one or more of hexane, pentane, cyclopentane, dichloromethane, carbon disulfide, ethyl acetate, trichloromethane and cyclohexane.

Further, the step of mixing and emulsifying the linearized macromolecular rubber, the first emulsifier and water comprises: preparing a first soap solution from a first emulsifier and water; adding the supernatant containing the linearized macromolecular rubber into the first soap solution, stirring for 5-60 min at a stirring speed of 100-1000 rpm, and shearing for 5-30 min at a shearing rate of 2000-8000 rpm to obtain a primary product; and distilling the primary product under reduced pressure to remove the second solvent in the primary product to obtain the rubber emulsion.

Further, the method of subjecting the waste rubber to the step of devulcanizing degradation employs one of the following methods:

the method comprises the following steps: in supercritical carbon dioxide, putting a mixture of rubber powder of waste rubber and a photocatalyst under ultraviolet light for photocatalytic desulfurization reaction to obtain linear active rubber; preferably, the photocatalyst is a composite inorganic photocatalyst; more preferably, the photocatalyst is selected from Co-doped TiO₂、ZrO₂/ZnO composite and ZrO₂/TiO₂One or more of the complexes; further preferably, the amount of the photocatalyst is 0.5-3% of the weight of the waste rubber powder;

the second method comprises the following steps: pretreating rubber powder of waste rubber and a regenerating agent at the temperature of 60-150 ℃ for 10-30 min, and standing at the temperature of 50-120 ℃ for 6-36 h to obtain a pretreated product; extruding the pretreated product in a screw extruder, wherein the extrusion temperature is 100-480 ℃, the extrusion pressure is 3-15 Mpa, and the reaction time is 1-15 min to obtain the linear active rubber; preferably, the regenerant comprises a softener selected from one or more of coal tar, pine tar, tall oil, naphthenic oil, dipentene, paraffin oil, oleic acid and rosin, and an activator selected from one or more of aromatic disulfide, polyalkylphenol sulfide, phenyl mercaptan and n-butylamine; preferably, the weight ratio of the waste rubber powder to the softener to the activator is 100: (5-30): (0.5-5).

The third method comprises the following steps: the step of devulcanizing and degrading the waste rubber comprises the following steps: placing rubber powder of waste rubber into a vertical depolymerizer, adding a solvent, a desulfurization catalyst and a cocatalyst, and then performing desulfurization reaction at the temperature of 160-180 ℃ and under the pressure of 0.5-0.7 MPa to obtain linear active rubber; wherein the solvent is paraffin oil and/or solid coumarone, the desulfurization catalyst is phthalic anhydride, and the cocatalyst is formalin and/or resorcinol.

Further, the emulsified modified asphalt is prepared by the following method: heating the matrix asphalt to 160-185 ℃, adding the elastomer polymer, and stirring for 20-40 min at the stirring speed of 1000-3000 rpm to obtain a premix; then, shearing the premix for 5-15 min at the temperature of 160-185 ℃ by using a high-speed shearing emulsifying machine at the shearing speed of 5000-12000 rpm to obtain a sheared substance; finally, stirring the sheared product at the temperature of 160-185 ℃ for 1-4 hours at the stirring speed of 1000-3000 rpm to obtain modified asphalt; dissolving a first reinforcing filler in water, stirring and standing, and taking supernatant as an aqueous solution of the first reinforcing filler; then adding a second emulsifier into the aqueous solution of the first reinforcing filler to obtain a second soap solution; and heating the second soap solution to 60-80 ℃, heating the modified asphalt to 150-175 ℃, mixing the second soap solution and the modified asphalt, shearing the mixture in an emulsifying machine, and cooling to obtain the emulsified modified asphalt.

Further, the step of preparing the aqueous coagulant solution comprises: dissolving a second reinforcing filler in water, stirring and standing, and taking supernatant as an aqueous solution of the second reinforcing filler; the coagulant is mixed with an aqueous solution of a second reinforcing filler to obtain an aqueous coagulant solution.

The invention provides a water-based non-cured rubber asphalt waterproof coating, which comprises a component A and a component B, wherein the weight ratio of the component A to the component B is (20-40) to (2-10); the component A comprises emulsified modified asphalt and waste rubber emulsion, the waste rubber emulsion comprises linearized macromolecular rubber, a first emulsifier and water, wherein the linearized macromolecular rubber is obtained by sequentially carrying out desulfurization treatment and micromolecule removal on the waste rubber, and the molecular weight of the linearized macromolecular rubber is more than 10000; and the first emulsifier is a first anionic emulsifier; the component B is coagulant water solution.

The water-based non-cured rubber asphalt waterproof coating does not contain volatile organic solvents, and is good in environmental protection; when the emulsion breaker is used, the emulsion breaking system can quickly break emulsion under the action of the coagulant aqueous solution after the component A and the component B are mixed, and has a good emulsion breaking effect. More importantly, the linearized macromolecular rubber in the waste rubber emulsion adopted in the invention is obtained by sequentially carrying out desulfurization treatment and micromolecule removal on waste rubber, and the molecular weight of the rubber is more than 10000. The linearized rubber with larger molecular weight can more fully exert the flexibility, cohesion and the like of the rubber, and the linearized macromolecular rubber obtained by desulfurization treatment and removal of small molecules contains more terminal functional groups, so that the water-based non-cured rubber asphalt waterproof coating has good bonding performance and stronger adhesion with a contact surface. Meanwhile, after the waste rubber is subjected to desulfurization treatment, part of carbon black, an anti-aging agent and the like are carried in the linear macromolecular rubber, so that the aging resistance of the coating can be further enhanced, and the stability of the coating can be maintained for a long time. In addition, the raw material cost of the water-based non-cured waterproof coating can be greatly reduced by adopting the waste rubber emulsion.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail with reference to examples.

As described in the background of the invention section, the aqueous non-curable waterproof coating in the prior art cannot have the performances of environmental protection, emulsion breaking effect, low cost and the like.

In order to solve the problems, the invention provides a water-based non-cured rubber asphalt waterproof coating which comprises a component A and a component B, wherein the weight ratio of the component A to the component B is (20-40) to (2-10); the component A comprises emulsified modified asphalt and waste rubber emulsion, the waste rubber emulsion comprises linearized macromolecular rubber, a first emulsifier and water, wherein the linearized macromolecular rubber is obtained by sequentially carrying out desulfurization treatment and micromolecule removal on the waste rubber, and the molecular weight of the linearized macromolecular rubber is more than 10000; and the first emulsifier is a first anionic emulsifier; the component B is coagulant water solution.

In the process of storing the aqueous non-curable rubber asphalt waterproofing paint, the component A and the component B are stored separately. And (4) after the mixture is in an actual construction site, mixing and stirring the component A and the component B, and spraying.

In order to further balance the properties of the water-based non-curable waterproof coating, in a preferred embodiment, the solid content of the waste rubber emulsion is 30-70%. Preferably, the waste rubber emulsion comprises 40-70 parts by weight of the linearized macromolecular rubber, 0.3-10 parts by weight of the first emulsifier and 30-40 parts by weight of water. The dosage relation among the linear macromolecular rubber, the first emulsifier and the water is controlled in the range, which is beneficial to further improving the stability of the waste rubber emulsion. In the manufacturing process, the waste rubber emulsion and the emulsified modified asphalt have better mixing and dispersing effects.

Under the aim of the invention, the water-based non-curing waterproof coating has better adhesion performance, extensibility, low-temperature flexibility and heat resistance. In a preferred embodiment, the weight ratio of the emulsified modified asphalt to the waste rubber emulsion is (60-80): 20-40); preferably, the emulsified modified asphalt comprises modified asphalt, an aqueous solution of a first reinforcing filler and a second emulsifier, wherein the second emulsifier is a second anionic emulsifier. The addition of the aqueous solution of the first reinforcing filler enables the water-repellent coating layer to be reinforced. And the aqueous solution of the first reinforcing filler is used as the emulsified modified asphalt raw material, which is equivalent to the first reinforcing filler which can be introduced in the stage of preparing the emulsified modified asphalt raw material, thereby better promoting the dispersibility of the reinforcing filler in an emulsion system.

Preferably, the emulsified modified asphalt comprises 50-70 parts of modified asphalt, 29-47 parts of aqueous solution of a first reinforcing filler and 1-3 parts of a second emulsifier by weight. The emulsified modified asphalt has better stability in the proportion. More preferably, the modified asphalt comprises 100 parts by weight of base asphalt and 1-5 parts by weight of elastomer polymer. The low temperature and extensibility of the matrix asphalt can be further improved by using a small amount of the elastomer polymer, so that the performance of the whole waterproof coating can be further improved.

The base asphalt can be of a type commonly used in the field, such as 70-120 # petroleum asphalt. Preferably, the elastomeric polymer includes, but is not limited to, one or more of SBS, SBR, and NR.

In a preferred embodiment, the first anionic emulsifier and the second anionic emulsifier are each selected from one or more of carboxylate, sulfate, sulfonate and phosphate salts. The emulsifiers can stabilize the aqueous emulsions in the component A, and the component A can be quickly demulsified by being matched with the coagulant. Specifically, the first anionic emulsifier and the second anionic emulsifier are respectively selected from sodium octadecyl benzene sulfonate, sodium dodecyl benzene sulfonate, sodium lignin sulfonate and the like.

The reinforcing filler used above may be of the type commonly used in the rubber field, and in a preferred embodiment, the first reinforcing filler in the aqueous solution of the first reinforcing filler is one or more of nanoclay, kaolin, diatomaceous earth, bentonite, talc and calcium powder; preferably, the solid content of the aqueous solution of the first reinforcing filler is 10-30%.

In a preferred embodiment, the aqueous coagulant solution comprises an aqueous solution of a coagulant and a second reinforcing filler. This may further introduce a portion of the reinforcing filler into the final water-repellent coating by means of an aqueous coagulant solution, thus contributing to further improvement of the strength of the water-repellent coating. Preferably, the aqueous coagulant solution includes, by weight, 5 to 15 parts of the coagulant and 85 to 95 parts of the second reinforcing filler.

In a preferred embodiment, the accelerator is selected from one or more of magnesium chloride, calcium chloride, aluminium sulphate, aluminium potassium sulphate, polyphosphazene ferric chloride and polyphosphazene aluminium chloride; preferably, the second reinforcing filler in the aqueous solution of the second reinforcing filler is one or more of nano clay, kaolin, diatomite, bentonite, talcum powder and calcium powder, and more preferably, the solid content of the aqueous solution of the first reinforcing filler is 10-30%.

According to another aspect of the present invention, there is also provided a preparation method of the above water-based non-curable rubber asphalt waterproof coating, which comprises the following steps: mixing and dispersing the emulsified modified asphalt and the waste rubber emulsion to obtain a component A; preparing a coagulant aqueous solution as component B; wherein the waste rubber emulsion is prepared by the following method: performing desulfurization degradation on the waste rubber to obtain linear active rubber; wherein the weight percentage content of the linearized molecules in the linearized active rubber is more than or equal to 75 percent; extracting linear macromolecular rubber with the molecular weight more than 10000 from the linear active rubber; mixing and emulsifying the linearized macromolecular rubber, the first emulsifier and water to obtain the waste rubber emulsion.

The water-based non-cured rubber asphalt waterproof coating prepared by the method does not contain volatile organic solvents, and is good in environmental protection property; when the emulsion breaker is used, the emulsion breaking system can quickly break emulsion under the action of the coagulant aqueous solution after the component A and the component B are mixed, and has a good emulsion breaking effect. More importantly, the linearized macromolecular rubber in the waste rubber emulsion adopted in the invention is obtained by sequentially carrying out desulfurization treatment and micromolecule removal on waste rubber, and the molecular weight of the rubber is more than 10000. The linearized rubber with larger molecular weight can more fully exert the flexibility, cohesion and the like of the rubber, and the linearized macromolecular rubber obtained by desulfurization treatment and removal of small molecules contains more terminal functional groups, so that the water-based non-cured rubber asphalt waterproof coating has good bonding performance and stronger adhesion with a contact surface. Meanwhile, after the waste rubber is subjected to desulfurization treatment, part of carbon black, an anti-aging agent and the like are carried in the linear macromolecular rubber, so that the aging resistance of the coating can be further enhanced, and the stability of the coating can be maintained for a long time. In addition, the raw material cost of the water-based non-cured waterproof coating can be greatly reduced by adopting the waste rubber emulsion. The component A and the component B jointly form the water-based non-cured rubber asphalt waterproof coating, and the water-based non-cured rubber asphalt waterproof coating is stored separately during storage and is mixed and coated according to a proportion during actual construction.

In a preferred embodiment, the step of extracting the linearized macromolecular rubber comprises: mixing the linearized active rubber with a first solvent to dissolve small molecules with the molecular weight less than 10000 in the linearized active rubber to obtain a first mixture; carrying out first solid-liquid separation on the first mixture, and drying and precipitating to obtain a pre-separated substance; mixing the pre-separated substance with a second solvent to dissolve the linear macromolecular rubber with the molecular weight more than 10000 in the pre-separated substance to obtain a second mixture; carrying out second solid-liquid separation on the second mixture to obtain supernatant containing the linearized macromolecular rubber; and in the process of mixing and emulsifying the linearized macromolecular rubber, the first emulsifier and water, adding the linearized macromolecular rubber in the form of supernatant, and removing the second solvent in the system after the emulsifying step to obtain the waste rubber emulsion.

By using the extraction method, after the linearized active rubber is mixed with the first solvent, small molecules with small molecular weight are dissolved in the first solvent, and linearized large molecules with large molecular weight, a small amount of gel-state rubber and a small amount of insoluble impurities cannot be dissolved. After the first solid-liquid separation, the insoluble matter is separated. Mixing the pre-separated matter and the second solvent, dissolving the linear macromolecular rubber in the second solvent, and separating the linear macromolecular rubber from a small amount of gel and insoluble impurities through the second solid-liquid separation to obtain supernatant containing the macromolecular linear component with molecular weight greater than 10000. In the emulsification step, the supernatant is mixed with a first emulsifier and water for emulsification, and then a second solvent is added in the system, and the second solvent is removed to form the waste rubber emulsion.

The first solvent serves to dissolve small molecules in the linearized active rubber, the second solvent serves to dissolve linearized large molecules in the pre-isolate, and in a preferred embodiment, the first solvent is one or more of acetone (56.53 ℃), ethanol (78 ℃), diethyl ether (34.6 ℃), isopropanol (82.4 ℃) (boiling point in parentheses); preferably, the second solvent is one or more of hexane (69 ℃), pentane (36 ℃), cyclopentane (49.3 ℃), dichloromethane (39.8 ℃), carbon disulfide (46.5 ℃), ethyl acetate (77.2 ℃), chloroform (61.3 ℃), cyclohexane (80.7 ℃) (boiling point in parentheses). The solvent is adopted to extract the linear macromolecular rubber component in the linear active rubber, so that the extraction effect is better.

The above specific extraction process can be adjusted, in order to further improve the extraction effect, in a preferred embodiment, in the step of mixing the linearized active rubber with the first solvent, the mixing temperature is lower than the boiling point of the first solvent, the difference between the mixing temperature and the boiling point of the first solvent is less than 10 ℃, the mixing time is 1-24 h, and the stirring speed is 100-1000 rpm; preferably, in the step of mixing the pre-separated substance and the second solvent, the mixing temperature is lower than the boiling point of the second solvent, the difference between the mixing temperature and the boiling point of the second solvent is less than 25 ℃, the mixing time is 1-24 h, and the stirring speed is 100-1000 rpm.

More preferably, the first solid-liquid separation and/or the second solid-liquid separation is centrifugal separation, the rotating speed of the centrifugal separation is 5000-12000 rpm, and the centrifugal time is 3-20 min; preferably, in the step of drying the precipitate, the drying temperature is 90-130 ℃, and the drying time is 2-10 h.

In the above emulsification process to the waste rubber emulsion, in order to further improve the emulsification effect, the step of mixing and emulsifying the linearized macromolecular rubber, the first emulsifier and the water comprises: preparing a first soap solution from a first emulsifier and water; adding the supernatant containing the linearized macromolecular rubber into the first soap solution, stirring for 5-60 min at a stirring speed of 100-1000 rpm, and shearing for 5-30 min at a shearing rate of 2000-8000 rpm to obtain a primary product; and distilling the primary product under reduced pressure to remove the second solvent in the primary product to obtain the rubber emulsion.

More preferably, in the vacuum distillation process, the vacuum degree is 20-100 KPa, the vacuum distillation temperature is lower than the boiling point of the second solvent, the difference between the vacuum distillation temperature and the boiling point of the second solvent is less than 5 ℃, and the vacuum distillation time is 0.5-6 h. Under the process condition, the reduced pressure distillation is carried out under the micro-boiling state of the second solvent, which is more beneficial to removing the second solvent in the emulsification system.

The linearized active rubber can be prepared by performing physical shearing desulfurization or high-temperature boiling degradation on waste rubber powder, and is preferably prepared by the following steps:

physical shearing desulfurization:

pretreating rubber powder of waste rubber and a regenerating agent at the temperature of 60-150 ℃ for 10-30 min, and standing at the temperature of 50-120 ℃ for 6-36 h to obtain a pretreated product; and extruding the pretreated product in a screw extruder, wherein the extrusion temperature is 100-480 ℃, the extrusion pressure is 3-15 Mpa, and the reaction time is 1-15 min, so as to obtain the linear active rubber. Preferably, the regenerant comprises a softener selected from one or more of coal tar, pine tar, tall oil, naphthenic oil, dipentene, paraffin oil, oleic acid, and rosin, and an activator selected from one or more of aromatic disulfide, polyalkylphenol sulfide, phenyl mercaptan, and n-butylamine. Preferably, the weight ratio of the waste rubber powder to the softener to the activator is 100: (5-30): (0.5-5).

Degradation by a high-temperature boiling method:

placing rubber powder of waste rubber into a vertical depolymerizer, adding a solvent, a desulfurization catalyst and a cocatalyst, and then performing desulfurization reaction at the temperature of 160-180 ℃ and under the pressure of 0.5-0.7 MPa to obtain linear active rubber; wherein the solvent is paraffin oil and/or solid coumarone, the desulfurization catalyst is phthalic anhydride, and the cocatalyst is formalin and/or resorcinol. Preferably, the raw materials in the preparation method comprise the following components in parts by weight: 100 parts of 20-50 mesh waste rubber powder, 70-90 parts of paraffin oil, 10-30 parts of solid coumarone, 2-5 parts of phthalic anhydride, 4-6 parts of formaldehyde aqueous solution and 0.2-0.5 part of resorcinol.

Compared with the physical shearing desulfurization or high-temperature boiling degradation, the more preferable linear active rubber is prepared by adopting the following method:

in supercritical carbon dioxide, a mixture of rubber powder of waste rubber and a photocatalyst is placed under ultraviolet light for photocatalytic desulfurization reaction to obtain the linearized active rubber. The waste rubber powder can be swelled by using the supercritical carbon dioxide, so that the aperture of the three-dimensional cross-linked network in the waste rubber powder is increased, and the photocatalyst is permeated into the waste rubber powder from the surface by virtue of the diffusion effect of the supercritical carbon dioxide fluid. Secondly, the photocatalyst generates a large amount of active groups under the irradiation of ultraviolet light to catalyze the breakage of S-S bonds in the waste rubber powder, thereby realizing the desulfurization and crosslinking of the waste rubber powder. Particularly, as the supercritical carbon dioxide also has excellent dissolving effect, the linear molecules formed by the desulfurization and the de-crosslinking on the surface of the waste rubber powder can be quickly peeled off from the surface of the waste rubber powder and dissolved in the supercritical carbon dioxide. Along with the continuous reaction, the waste rubber powder continuously carries out the cyclic reciprocating of 'catalyst surface permeation, photocatalytic desulfurization and desulfurization linear molecule stripping dissolution' until the waste rubber powder integrally completes desulfurization and de-crosslinking to form the linear active rubber.

Different from the mechanical shearing desulfurization regeneration method, the photocatalytic desulfurization is carried out under the swelling action of supercritical carbon dioxide, so that the method has higher selectivity on the breaking point of a cross-linked network, and the breaking point is mostly at the S-S bond cross-linking part. While the breaking point of mechanical shear desulfurization is a diversified breaking point that is not selective for S-S bond crosslinks. Therefore, based on the preparation method, the linearization structure of the rubber can be more completely maintained, and the regenerated linearization active rubber has higher molecular weight and correspondingly maintains higher performance, thereby being more beneficial to exerting the flexibility of the rubber in secondary utilization.

Compared with the mode of degradation by a high-temperature boiling method, the photocatalytic desulfurization is carried out under the swelling action of the supercritical carbon dioxide without adding a chemical desulfurizer, so that the problems of delayed vulcanization, secondary degradation and the like caused by chemical desulfurization and residue are avoided. Meanwhile, a large amount of softening additives are not added to the high-temperature boiling method, so that the influence of the softening additives on later-stage utilization is favorably avoided.

The above-mentioned photocatalyst may be of a type commonly used in the field of photocatalytic technology. In a preferred embodiment, the photocatalyst is a composite inorganic photocatalyst. The composite inorganic photocatalyst has higher catalytic activity and higher selective fracture performance on S-S crosslinking points in the waste rubber powder. More preferably, the photocatalyst is selected from Co-doped TiO₂、ZrO₂/ZnO composite and ZrO₂/TiO₂One or more of the complexes. The surface areas of the composite inorganic photocatalysts are greatly increased, so that the probability of exciting the photohole electrons under ultraviolet irradiation is further increased, and the composite inorganic photocatalysts have higher catalytic activity.

In a preferred embodiment, the process for preparing a linearized active rubber comprises the steps of: mixing rubber powder of waste rubber with a photocatalyst to obtain a mixture; under the condition of stirring, putting the mixture into supercritical carbon dioxide for swelling treatment to obtain a swelling mixture; and irradiating ultraviolet light to the swelling mixture in supercritical carbon dioxide to perform photocatalytic desulfurization reaction, thereby obtaining the linearized active rubber.

Thus, mixing the waste rubber powder with the photocatalyst in advance enables the photocatalyst to be dispersed in the waste rubber powder in advance. Secondly, the mixture is placed in supercritical carbon dioxide under the condition of stirring for swelling treatment, so that the diffusion effect of supercritical carbon dioxide fluid can be more fully exerted, the waste rubber powder is swelled as soon as possible, and the photocatalyst is enabled to permeate into the surface of the waste rubber powder more quickly. Finally, irradiating ultraviolet light to the system for photocatalytic desulfurization reaction. In the actual operation process, the desulfurization efficiency of the waste rubber powder can be further improved according to the process.

In a preferred embodiment, the swelling treatment step comprises: injecting carbon dioxide gas into a system in which the mixture is located, and then adjusting the temperature of the system to 80-140 ℃ and the pressure to 10-35 MPa to convert the carbon dioxide gas into a supercritical state so as to form supercritical carbon dioxide; and swelling the mixture for 30-120 min under the stirring condition that the stirring speed is 200-700 rpm, so as to obtain a swelling mixture. The swelling treatment is carried out in the technical process, the aperture of the cross-linked network of the waste rubber powder is larger, and the photocatalyst can be more fully permeated and more uniformly dispersed in the rubber network, so that on one hand, the desulfurization efficiency of the waste rubber powder can be further improved, and simultaneously, the fracture number of S-S bonds can be further improved, thereby improving the desulfurization degree of the waste rubber powder and obtaining the desulfurized rubber with higher linearization degree.

More preferably, the swelling treatment step comprises: injecting carbon dioxide gas into a system in which the mixture is located, and then adjusting the temperature of the system to 105-140 ℃ and the pressure to 28-35 MPa to convert the carbon dioxide gas into a supercritical state so as to form supercritical carbon dioxide; and swelling the mixture for 90-120 min under the condition that the stirring speed is 500-700 rpm, so as to obtain a swelling mixture. The desulfurization efficiency and desulfurization degree under the process condition are higher.

In a preferred embodiment, in the step of photocatalytic desulfurization, the reaction temperature is 80-140 ℃ and the reaction pressure is 10-35 MPa. Under the reaction conditions, the S-S bond desulfurization selectivity of the photocatalyst is higher, and the desulfurization degree and the desulfurization linearization degree of the waste rubber powder are higher. More preferably, the reaction temperature in the step of the photocatalytic desulfurization reaction is 105-140 ℃, and the reaction pressure is 28-35 MPa. In the actual production process, after the photocatalytic desulfurization reaction is finished, the method preferably further comprises the following steps: and (3) decompressing the reaction system, recovering carbon dioxide, stopping illumination and cooling to obtain the linearized active rubber.

In a preferred embodiment, in the step of photocatalytic desulfurization, the illumination time of the ultraviolet light is 5 to 30min, preferably 20 to 30min, and the wavelength of the ultraviolet light is 300 to 400nm, preferably 350 to 390 nm. Under the illumination condition, the photocatalyst has higher activity, and the desulfurization effect of the waste rubber powder is better.

In a preferred embodiment, the step of mixing the waste rubber powder with the photocatalyst comprises: and stirring and mixing the waste rubber powder and the photocatalyst for 5-30 min under the condition that the stirring speed is 700-1500 rpm to obtain a mixture. The waste rubber powder and the photocatalyst are mixed according to the process, and the waste rubber powder and the photocatalyst can be mutually dispersed more fully. Preferably, the waste rubber powder and the photocatalyst are stirred and mixed to the temperature of 60-85 ℃ to obtain a mixture. Shear heating can occur in the stirring process, the stirring and mixing temperature is controlled to be 60-85 ℃, and performance influence caused by overheating can be prevented on the basis of sufficient dispersion.

As described above, based on the diffusibility and good solubility of supercritical carbon dioxide, the cyclic process of "catalyst surface permeation-photocatalytic desulfurization-desulfurization linear molecule stripping dissolution" is continuously performed in the step of photocatalytic desulfurization reaction of waste rubber powder, which enables the preparation method of the present invention to achieve a higher desulfurization degree by using the cyclic process with less photocatalyst. For the purposes of saving energy and improving the desulfurization efficiency and the desulfurization degree, in a preferred embodiment, the amount of the photocatalyst is 0.5 to 3 percent, preferably 2 to 3 percent of the weight of the waste rubber powder.

In a preferred embodiment, the particle size of the waste rubber powder is 80-120 meshes; preferably, the waste rubber powder is one or more of waste tire rubber powder, waste mechanical tire rubber powder, waste sole rubber powder and waste conveyor belt rubber powder. In addition, the preparation method is suitable for waste rubber powder commonly used in the field, such as one or more of waste nitrile rubber powder, waste natural rubber powder, waste butyl rubber powder, waste ethylene propylene rubber powder and waste styrene butadiene rubber powder.

In a preferred embodiment, the emulsified modified asphalt is prepared by the following method:

heating the matrix asphalt to 160-185 ℃, adding the elastomer polymer, and stirring for 20-40 min at the stirring speed of 1000-3000 rpm to obtain a premix; then, shearing the premix for 5-15 min at the temperature of 160-185 ℃ by using a high-speed shearing emulsifying machine at the shearing speed of 5000-12000 rpm to obtain a sheared substance; finally, stirring the sheared product at the temperature of 160-185 ℃ for 1-4 hours at the stirring speed of 1000-3000 rpm to obtain modified asphalt; dissolving a first reinforcing filler in water, stirring and standing, and taking supernatant as an aqueous solution of the first reinforcing filler; then adding a second emulsifier into the aqueous solution of the first reinforcing filler to obtain a second soap solution; and heating the second soap solution to 60-80 ℃, heating the modified asphalt to 150-175 ℃, mixing the second soap solution and the modified asphalt, shearing the mixture in an emulsifying machine, and cooling to obtain the emulsified modified asphalt. Under the condition, the emulsifying effect of the emulsified asphalt is further improved, and the first reinforcing filler forms good dispersion in the emulsified modified asphalt.

In a preferred embodiment, the step of preparing the aqueous coagulant solution comprises: dissolving a second reinforcing filler in water, stirring and standing, and taking supernatant as an aqueous solution of the second reinforcing filler; the coagulant is mixed with an aqueous solution of a second reinforcing filler to obtain an aqueous coagulant solution.

The present application is described in further detail below with reference to specific examples, which should not be construed as limiting the scope of the invention as claimed.

Preparation of linearized active rubber:

examples 1 to 17

In these examples, the following processes were used to conduct the devulcanization regeneration of the waste rubber:

step 1: putting 80-mesh waste tire rubber powder and a photocatalyst into a high-speed stirring and mixing unit, stirring at the stirring speed of 1000rpm for 20min to 70 ℃, stopping stirring, putting the materials into a cooling unit, cooling and discharging to obtain a mixture;

step 2: putting the mixture into a supercritical carbon dioxide reaction kettle, injecting carbon dioxide gas into the reaction kettle by using a high-pressure pump to adjust the pressure in the reaction kettle, and simultaneously heating to convert the carbon dioxide gas into a supercritical state; starting stirring to swell the mixture in supercritical carbon dioxide to obtain a swollen mixture;

and step 3: maintaining the supercritical carbon dioxide environment, starting a built-in ultraviolet light source to perform ultraviolet irradiation on the swelling mixture, and irradiating for a certain time;

and 4, step 4: and (5) releasing pressure and recovering carbon dioxide gas, stopping illumination and cooling, and taking out a target product and testing.

Examples 1 to 17 differ in the following parameters: the type and amount of the photocatalyst (weight percentage of the waste rubber powder), the temperature of the supercritical carbon dioxide system (same swelling temperature and desulfurization reaction temperature), the pressure (same swelling pressure and desulfurization reaction pressure), the swelling time, the ultraviolet light irradiation time and the ultraviolet light wavelength are shown in table 1:

TABLE 1

Example 18

The process flow in this example is the same as in example 9, except that:

step 1: and (3) putting 120-mesh waste tire rubber powder and a photocatalyst into a high-speed stirring and mixing unit, stirring at the stirring speed of 700rpm for 30min to 60 ℃, stopping stirring, putting the materials into a cooling unit, cooling and discharging to obtain a mixture.

Example 19

The process flow in this example is the same as in example 10, except that:

step 1: and (3) putting the 120-mesh waste sole rubber powder and the photocatalyst into a high-speed stirring and mixing unit, stirring at the stirring speed of 1500rpm for 30min to 85 ℃, stopping stirring, putting the materials into a cooling unit, cooling and discharging to obtain a mixture.

Example 20

The process flow in this example is the same as in example 10, except that:

step 1: and (3) putting the 80-mesh waste conveyor belt rubber powder and the photocatalyst into a high-speed stirring and mixing unit, stirring at the stirring speed of 600rpm for 10min to 40 ℃, stopping stirring, putting the materials into a cooling unit, cooling and discharging to obtain a mixture.

Example 21

100 parts of waste tire tread rubber powder with the particle size of 1mm is adopted, 6 parts of pine tar, 4 parts of naphthenic oil, 0.5 part of phenyl mercaptan and 0.5 part of n-butylamine are added as regenerants, and the mixture is mixed and stirred for 10min at the temperature of 100 ℃ in a stirrer and then is placed for 36h at the temperature of 50 ℃. It was then fed into a co-rotating twin-screw extruder (D30 mm, L/D52/1, six heating zones) via a feeding device: screw rotation speed 150rpm, 6 temperature zones: changing the internal thread composition of the screw at 120 ℃, 180 ℃, 230 ℃, 280 ℃, 150 ℃ and 100 ℃, and adding a right-handed thread element to ensure that the maximum pressure reaches 7.5 MPa. And (3) after reacting for 5min, extruding by a screw extruder die to obtain the reclaimed rubber.

Example 22

100kg of 30-mesh vulcanized rubber powder was put into a vertical depolymerizer, and 70kg of paraffin oil, 22kg of solid coumarone resin, 3kg of phthalic anhydride, 4.5kg of formalin and 0.5kg of resorcinol were sequentially added. And sealing the material port, stirring, heating to 180 ℃, controlling the pressure at 0.5MPa, reacting for 2.5 hours, cooling, discharging residual gas, discharging, and filtering by using a 100-mesh metal sieve to obtain the reclaimed rubber.

Comparative example 1

100 parts of waste tire rubber powder and 10 parts of nano cadmium sulfide are stirred and mixed uniformly by a high-speed plasticizing reaction unit. The rotating speed of the reaction unit is firstly adjusted to 1200rpm, when the temperature reaches 90 ℃, stirring is stopped, the materials are put into a cooling unit, the rotating speed is 50rpm, and when the temperature is about 30 ℃, discharging is carried out. Placing the stirred material into a stirrer, and irradiating the material with ultraviolet lamp for 30 min. The UV lamp used was a 3kw high pressure mercury lamp with UV wavelength of 365 nm.

The main machine rotating speed of the double-screw extruder is adjusted to be 220rpm, the feeding rotating speed is adjusted to be 15rpm, and the temperatures of 7 temperature zones of the double screws are as follows: 54-67-77-76-79-73-42 ℃, the temperature of each area is not higher than 100 ℃, the production state at normal temperature and normal pressure is realized, and the discharge detection is carried out.

Comparative example 2

The process flow in this comparative example is the same as in example 10, except that the system temperature: 30 ℃, pressure 7MPa, critical parameters of CO 2: 31.26 deg.C and 7.29MPa, carbon dioxide is in non-supercritical state.

The devulcanization effect characterization was performed on the devulcanized reclaimed rubbers prepared in examples 1 to 22, comparative examples 1 and 2(D1 and D2), and the characterization results are shown in table 2, and the characterization methods are as follows:

the following treatments were carried out on each of the above products:

firstly, acetone is used as a solvent, and a Soxhlet extraction method is adopted to continuously extract for 48 hours until small molecules (acetone soluble substances) are completely extracted and separated by the acetone. Subsequently, the soluble fraction was dried in a vacuum drying oven until the mass was unchanged, the insoluble fraction was dried until the mass was unchanged, and secondary extraction was continued using toluene as a solvent to separate a macromolecular soluble substance (toluene soluble substance) and a crosslinked insoluble substance (gel).

The average molecular weights of the acetone soluble substance and the toluene soluble substance and the polymer polydispersity number PDI are respectively tested (GPC test can be simultaneously characterized, and the molecular weights and the polydispersity numbers PDI are respectively tested) by the following methods: acetone-soluble and toluene-soluble substances were sufficiently swollen with toluene, and the number average molecular weight (M) of the sample was measured by using a GPC analyzer model 515-_n) And calculating the polydispersity index (PDI) by taking tetrahydrofuran as a mobile phase and polystyrene as a standard sample, and measuring the temperature at 35 ℃.

The crosslink density of the gel was measured as follows: the crosslinking density test employs an equilibrium swelling method. The weighed sample was placed in a ground conical flask with a stopper containing 150ml of a good solvent (toluene was used as a good solvent in this experiment), immersed in a constant temperature water bath, kept at 30 ℃ for 72 hours, taken out after equilibration, weighed with an analytical balance, and dried in a vacuum desiccator at 50 ℃ for 4 hours. When the sample swells to equilibrium in a suitable solvent, the solvent molecules enter the crosslinked network at the same rate as they are expelled. And obtaining a crosslinking density formula, namely a Flory-Rehner formula, according to the basis of the rubber elasticity statistical theory.

TABLE 2

The gel content, the sol content, the average molecular weight of the sol, the sol PDI and the gel crosslinking density are the most visual and accurate means for representing the degradation degree of the crosslinked rubber. Higher sol content, lower gel crosslink density, indicate higher rubber degradation. The higher the toluene solubles content and the higher the molecular weight at the same sol content, the higher the content of linearized macromolecules in the reclaimed rubber after decrosslinking. The weight percentage of the linearized molecule is the sol content/(sol content + gel content); the weight percentage of the gradient small molecules in the linearized molecule is acetone soluble content/(acetone soluble + toluene soluble content).

1. From the comparison of the data in the above examples and comparative example 2, it can be seen that: in the supercritical carbon dioxide fluid state, the same process means is adopted, and the desulfurization and degradation degree of the waste rubber is far higher than that in the non-supercritical state (the carbon dioxide critical point is 38 ℃ and 7.38 MPa). This is due to: in the supercritical state, the carbon dioxide fluid can fully exert the excellent dissolving and extracting performances of the rubber powder, and can fully dissolve linear macromolecules and micromolecules, the macromolecules firstly desulfurized and degraded on the surface of the waste rubber powder are disentangled through the swelling effect of the supercritical carbon dioxide fluid, and are peeled from the crosslinked rubber powder body and dissolved in the fluid. And then, under the action of illumination and a catalyst, the inner layer of the crosslinked rubber powder is continuously desulfurized and degraded and has the same action as the surface layer until the whole crosslinked waste rubber powder is desulfurized and degraded. The linearized active rubber is in a pasty and semi-fluid state at normal temperature. However, in a non-supercritical state, the surface of the waste rubber powder is subjected to desulfurization degradation under the action of illumination and a catalyst, and the surface layer subjected to desulfurization degradation still wraps the surface of the rubber powder due to the absence of the action of an external solvent, so that the rubber of the desulfurized surface layer blocks the penetration of ultraviolet light, namely, the illumination cannot reach the inside of the waste rubber powder, and the inside of the waste rubber powder still is in a three-dimensional cross-linked state. Therefore, even if photocatalytic degradation is carried out in a non-supercritical carbon dioxide state, the degradation efficiency and degree are low, sufficient desulfurization degradation of the crosslinked waste rubber component cannot be realized, and the basically fully uncrosslinked linearized rubber cannot be prepared;

2. as can be seen from the comparison of the data in the above examples and comparative examples 1 and 2, the method of the present invention provides a higher degree of desulfurization of the waste rubber crumb and a higher degree of linearization of the devulcanized rubber. In particular, the twin-screw mechanical devulcanization used in example 21 was carried out without differential chain scission of the three-dimensional crosslinked network in the waste rubber powder, and therefore, the gel content was relatively low, but at the same time, the small molecules content was high, the large molecules content was low, and the molecular weight of the large molecular chains was relatively low. The preparation methods adopted in examples 1 to 20 have the advantage of selective chain scission for S-S bonds and S-C bonds in the three-dimensional cross-linked network of the waste rubber powder, so that the desulfurization linearized active rubbers prepared in examples 1 to 20 of the present invention have higher macromolecular content than that of example 21. In example 22, the rubber powder is degraded by a high-temperature boiling method, and although the degree of degradation of the rubber powder is high, the content of gradient small components in the linearized active rubber is high and the content of linearized macromolecules is low because a large amount of small-molecule softeners (paraffin oil and solid coumarone) are added in the preparation method.

3. More particularly, as can be seen from the comparison of the data in examples 1 to 17 above, the use of the composite inorganic photocatalyst to optimize the processes in the swelling treatment step and the photocatalytic desulfurization reaction step can significantly improve the desulfurization regeneration degree of the waste rubber powder, resulting in a substantially fully uncrosslinked, linearized rubber. And the process is optimized, and the prepared fully-desulfurized de-crosslinked linearized rubber has high macromolecular polymer (rubber) content, large molecular weight and narrow macromolecular chain distribution coefficient (polydispersity index PDI).

4. When photocatalytic degradation is performed under supercritical carbon dioxide, the requirements on the wavelength of ultraviolet light are not strict, and the photocatalytic degradation can be realized within the wavelength range of 350-420.

Preparing a waste rubber emulsion:

examples 23 to 44, comparative examples 3 and 4(D3 and D4)

Examples 23 to 44, comparative examples 3 and 4 waste rubber emulsions were prepared by the following methods:

linearized active or reclaimed rubber: prepared from the above examples or comparative examples, the correspondence is detailed in table 3.

The preparation process comprises the following steps:

(1) 110kg of the linearized active rubber or the reclaimed rubber prepared in the above examples or comparative examples were thoroughly mixed and stirred with 300kg of acetone (boiling point 56.53 ℃ C.) for 12hr at a stirring rate: 500rpm, mixing temperature: 55 ℃; forming a first mixture;

(2) centrifuging the first mixture in a centrifuge at 10000rpm for 10min, and collecting the supernatant to obtain centrifuged precipitate;

(3) putting the precipitate into a drying oven at 130 deg.C for 4h, and taking out to obtain dried precipitate, which is called pre-isolate;

(4) mixing all the above pre-isolates with 300kg ethyl acetate (boiling point 77.2 deg.C) under stirring for 12hr at a stirring rate: 500rpm, mixing temperature: 55 ℃; forming a second mixture;

(5) centrifuging the second mixture in a centrifugal device at 10000rpm for 10min to obtain supernatant containing macromolecular linearized components;

(6) preparing 4.2kg of anionic emulsifier (sodium octadecyl benzene sulfonate) and 49kg of deionized water into a soap solution, adding the soap solution into the supernatant containing the macromolecular linearization component, stirring for 60min at the stirring speed of 500rpm, and shearing at the shearing speed of 4000rpm for 15 min; and (3) carrying out reduced pressure distillation, wherein the vacuum degree is 80KPa, the reduced pressure distillation temperature is controlled to be the micro-boiling temperature (75 ℃) of the solution, and the reduced pressure distillation time is 3h, and fully removing the small molecular solvent ethyl acetate to obtain the waste rubber emulsion.

Example 45:

a linearized activated rubber was prepared as described above in example 1.

The preparation process comprises the following steps:

(1) 110kg of the linearized active rubber prepared in the above example was thoroughly mixed with 300kg of acetone (boiling point 56.53 ℃) for 12hr under stirring at a rate of: 500rpm, mixing temperature: 55 ℃; forming a first mixture;

(6) preparing 2kg of anionic emulsifier (sodium octadecylbenzenesulfonate) and 25.8kg of deionized water into a soap solution, adding the soap solution into the supernatant containing the macromolecular linearized component, stirring for 60min at the stirring speed of 500rpm, and shearing at the shearing speed of 4000rpm for 15 min; and (3) carrying out reduced pressure distillation, wherein the vacuum degree is 80KPa, the reduced pressure distillation temperature is controlled to be the micro-boiling temperature (75 ℃) of the solution, and the reduced pressure distillation time is 3h, and fully removing the small molecular solvent ethyl acetate to obtain the waste rubber emulsion.

Example 46:

linearization of active rubber: prepared from example 1 above.

The preparation process comprises the following steps:

(1) 62.9kg of the linearized active rubber or the reclaimed rubber prepared in the above example and 300kg of acetone (boiling point 56.53 ℃) are fully mixed and stirred for 12 hours, and the stirring speed is as follows: 500rpm, mixing temperature: 55 ℃; forming a first mixture;

(6) preparing 8kg of anionic emulsifier (sodium octadecylbenzenesulfonate) and 50.5kg of deionized water into a soap solution, adding the soap solution into the supernatant containing the macromolecular linearized component, stirring for 60min at the stirring speed of 500rpm, and shearing at the shearing speed of 4000rpm for 15 min; and (3) carrying out reduced pressure distillation, wherein the vacuum degree is 80KPa, the reduced pressure distillation temperature is controlled to be the micro-boiling temperature (75 ℃) of the solution, and the reduced pressure distillation time is 3h, and fully removing the small molecular solvent ethyl acetate to obtain the waste rubber emulsion.

Example 47:

linearization of active rubber: prepared from example 20 above.

The preparation process comprises the following steps:

(1) 80.3kg of the linearized active rubber prepared in the above example was thoroughly mixed with 300kg of acetone (boiling point 56.53 ℃) for 12hr with a stirring rate: 500rpm, mixing temperature: 55 ℃; forming a first mixture;

(6) preparing 3.3kg of anionic emulsifier (sodium octadecyl benzene sulfonate) and 39kg of deionized water into a soap solution, adding the soap solution into the supernatant containing the macromolecular linearized component, stirring for 60min at the stirring speed of 500rpm, and shearing at the shearing speed of 4000rpm for 15 min; and (3) carrying out reduced pressure distillation, wherein the vacuum degree is 80KPa, the reduced pressure distillation temperature is controlled to be the micro-boiling temperature (75 ℃) of the solution, and the reduced pressure distillation time is 3h, and fully removing the small molecular solvent ethyl acetate to obtain the waste rubber emulsion.

Example 48:

linearization of active rubber: prepared from example 21 above.

The preparation process comprises the following steps:

(1) 97.2kg of the linearized active rubber or the reclaimed rubber prepared in the above example was thoroughly mixed with 300kg of acetone (boiling point 56.53 ℃ C.) for 12hr under stirring at a rate of: 500rpm, mixing temperature: 55 ℃; forming a first mixture;

Example 49:

linearization of active rubber: prepared from example 22 above.

The preparation process comprises the following steps:

(1) 147kg of the linearized active rubber prepared in the above example was thoroughly mixed with 300kg of acetone (boiling point 56.53 ℃) for 12hr under stirring at a rate of: 500rpm, mixing temperature: 55 ℃; forming a first mixture;

(6) preparing 3.3kg of anionic emulsifier (sodium octadecyl benzene sulfonate) and 39kg of deionized water into a soap solution, adding the soap solution into the supernatant containing the macromolecular linearized component, stirring for 60min at the stirring speed of 500rpm, and shearing at the shearing speed of 4000rpm for 15 min; and (3) carrying out reduced pressure distillation, wherein the vacuum degree is 80KPa, the reduced pressure distillation temperature is controlled to be the micro-boiling temperature (75 ℃) of the solution, the reduced pressure distillation time is 3h, and the small molecular solvent ethyl acetate is fully removed to obtain the rubber emulsion.

COMPARATIVE EXAMPLE 5(D5)

The raw materials are the same as in example 23, and the preparation process is as follows: 110kg of the linearized active rubber was swollen with 300kg of ethyl acetate to give a swollen mass. Preparing 4.2kg of emulsifier and 49kg of deionized water into a soap solution, adding the soap solution into the swelling substance, stirring for 60min at the stirring speed of 500rpm, and shearing at the shearing speed of 4000rpm for 15 min; and (3) carrying out reduced pressure distillation, wherein the vacuum degree is 80KPa, the reduced pressure distillation temperature is controlled to be the micro-boiling temperature (75 ℃) of the solution, the reduced pressure distillation time is 3h, and the small molecular solvent ethyl acetate is fully removed to obtain the rubber emulsion.

And (3) performance characterization:

characterizing the basic properties of each rubber emulsion, and measuring the particle size of the latex beam by using a British Marvin Nano ZS laser particle size tester; the total solid content, viscosity and mechanical stability are measured according to the GB/T14797.1-2008 (concentrated natural latex) test method; the average molecular weight of the macromolecular linearized component in the emulsion and the PDI test method were as follows: the macromolecular linearized fraction was fully swollen with toluene, and the number average molecular weight (M) of the sample was determined using a GPC analyzer type 515-_n) And calculating the polydispersity index (PDI) by taking tetrahydrofuran as a mobile phase and polystyrene as a standard sample, and measuring the temperature at 35 ℃. The characterization results are shown in Table 3:

TABLE 3

From the above results, it can be seen that: under the same emulsion preparation process conditions, the higher the content of the linearized macromolecules, the higher the solid content of the emulsion, while the case of low linearized macromolecule rubber requires more organic solvents as dissolution aids at the same emulsion solid content (as in examples 47, 48, 49); while the rubber emulsion (as in comparative example D5) can be prepared without removing the non-uncrosslinked portion (gel component) (i.e., without performing component separation), the emulsion has very poor stability (mechanical stability and emulsion bundle particles), and the storage stability of the rubber emulsion is greatly affected by such large emulsion micelle particles (due to the particle size of the non-degraded portion), and the emulsion bundle particle size is generally 4 to 20 μm according to the well-known emulsion data capable of being stored stably in the industry.

Preparing emulsified modified asphalt:

examples 50 to 55

Emulsifier: anionic emulsifiers

Base asphalt

Elastomeric polymers

First reinforcing filler

In examples 50 to 55, emulsified asphalt was prepared from the above raw materials, and the preparation process was the same as follows:

heating the matrix asphalt to 185 ℃, adding the elastomer polymer, keeping the temperature and stirring for 20min at the stirring speed of 3000rpm to obtain a premix; then, shearing the premix at 185 ℃ for 5min at 12000rpm by using a high-speed shearing emulsifying machine to obtain a sheared substance; finally, stirring the sheared substance at 185 ℃ for 1hr at the stirring speed of 3000rpm to obtain modified asphalt; dissolving a first reinforcing filler in water, stirring and standing, and taking supernatant as an aqueous solution (solid content is 10%) of the first reinforcing filler; then adding an emulsifier into the aqueous solution of the first reinforcing filler to obtain a second soap solution; and heating the second soap solution to 80 ℃, heating the modified asphalt to 150 ℃, mixing the second soap solution and the modified asphalt, shearing the mixture in an emulsifying machine, and cooling to obtain the emulsified modified asphalt.

The difference lies in that the types and the amounts of the raw materials are different, and are specifically shown in table 4:

TABLE 4

Preparation of water-based non-cured rubber asphalt waterproof coating

Examples 56 to 69, comparative example 6(D6)

The water-based non-curing rubber asphalt waterproof coating materials are prepared in the examples 56 to 69 and the comparative example 6(D6), and the preparation process is the same as follows:

preparation of aqueous coagulant solution of component B: dissolving the second reinforcing filler in water, stirring and standing, and taking supernatant as an aqueous solution (with the solid content of 10%) of the second reinforcing filler; the coagulant (calcium chloride) is mixed with an aqueous solution of a second reinforcing filler to obtain an aqueous coagulant solution.

Preparation of component A: the emulsified modified asphalt and the waste rubber emulsion prepared in the foregoing examples or comparative examples were mixed and dispersed to obtain component a.

When in use, the A/B components are mixed and sprayed on a base surface, and the non-cured rubber asphalt waterproof coating which is fully adhered to the base surface is formed through demulsification.

The types or sources of the emulsified modified asphalt, the waste rubber emulsion, the coagulant, the aqueous solution of the second reinforcing filler, and the parts by weight used in each example or comparative example are shown in Table 5:

TABLE 5

The performance of the water-based non-cured waterproof coating prepared by the method is characterized, and the characterization method and the result are as follows:

according to the standard JC/T2428-2017, the results of the detection of the non-cured rubber asphalt waterproof coating are shown in the table 6:

TABLE 6

As can be seen from the above examples 56 to 61, as the solid content of the waste rubber emulsion and the molecular weight of the linearized macromolecular rubber component therein increase, the elongation and low-temperature flexibility of the non-cured coating material significantly increase, the increase in heat resistance is large, and the properties after heat aging are substantially unchanged. The linearized macromolecular rubber in the waste rubber emulsion has better low-temperature flexibility, and can be better entangled with asphalt and other components in a non-cured coating, so that the non-cured coating can better resist external force damage, is reflected in the performance of the non-cured coating, and can better improve the heat resistance, the low-temperature flexibility and the extensibility of the non-cured coating. The linear macromolecular rubber contains partial free carbon black and an anti-aging auxiliary agent, so that the thermal aging can be effectively resisted, the thermal stability of the non-cured coating is reflected, and the performance of the non-cured coating is basically maintained unchanged.

As can be seen from examples 59, 62, 63, the properties of the uncured coating remained essentially consistent by varying the elastomeric polymer in the emulsified modified asphalt; it can be seen from examples 64 and 66 that the addition of the nanoscale filler to the system is effective in improving the heat resistance of the non-curable coating, which is related to the better dispersion of the nanoscale filler in the system and the increased cohesion of the system.

As can be seen from the results of comparative example D6 and other examples, the uncured coatings prepared from the suspension of the rubber powder had a large difference in heat resistance, elongation, low temperature flexibility and heat aging resistance. The rubber powder particles exist in a cross-linking state in a system, actually, stress concentration points of the system are increased, the resistance to external force damage is weak, so that the heat resistance and the extensibility of the non-cured coating are greatly reduced, the thermal movement capacity of rubber molecular chains of the cross-linking state rubber powder is weak, the low-temperature flexibility of the non-cured coating is poor, carbon black and an anti-aging auxiliary agent contained in the rubber powder exist in a combined state, the anti-aging effect cannot be fully exerted, and the thermal aging performance of the non-cured coating is poor.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The water-based non-cured rubber asphalt waterproof coating is characterized by comprising a component A and a component B, wherein the weight ratio of the component A to the component B is (20-40) to (2-10); wherein the content of the first and second substances,

the component A comprises emulsified modified asphalt and waste rubber emulsion, wherein the waste rubber emulsion comprises linearized macromolecular rubber, a first emulsifier and water, the linearized macromolecular rubber is obtained by sequentially carrying out desulfurization treatment and micromolecule removal on the waste rubber, and the molecular weight of the linearized macromolecular rubber is more than 10000; and the first emulsifier is a first anionic emulsifier;

the component B is coagulant water solution;

wherein the linearized macromolecular rubber is obtained by the following method:

mixing the linearized active rubber with a first solvent to dissolve small molecules with the molecular weight less than 10000 in the linearized active rubber to obtain a first mixture;

carrying out first solid-liquid separation on the first mixture, and drying and precipitating to obtain a pre-separated substance;

mixing the pre-separated substance with a second solvent to dissolve the linear macromolecular rubber with the molecular weight more than 10000 in the pre-separated substance to obtain a second mixture;

carrying out second solid-liquid separation on the second mixture to obtain supernatant containing the linearized macromolecular rubber;

adding the linearized macromolecular rubber in the form of the supernatant in the process of mixing and emulsifying the linearized macromolecular rubber, the first emulsifier and water, and removing the second solvent in the system after the emulsifying step to obtain the waste rubber emulsion;

the first solvent is one or more of acetone, ethanol, diethyl ether and isopropanol; the second solvent is one or more of hexane, pentane, cyclopentane, dichloromethane, carbon disulfide, ethyl acetate, trichloromethane and cyclohexane;

in the step of mixing the linearized active rubber and the first solvent, the mixing temperature is lower than the boiling point of the first solvent, the difference between the mixing temperature and the boiling point of the first solvent is less than 10 ℃, the mixing time is 1-24 h, and the stirring speed is 100-1000 rpm; and in the step of mixing the pre-separated matter and the second solvent, the mixing temperature is lower than the boiling point of the second solvent, the difference between the mixing temperature and the boiling point of the second solvent is less than 25 ℃, the mixing time is 1-24 h, and the stirring speed is 100-1000 rpm.

2. The water-based non-curable rubber asphalt waterproof coating material according to claim 1, wherein the solid content of the waste rubber emulsion is 30 to 70%.

3. The aqueous non-curable rubber asphalt waterproofing coating according to claim 2, wherein the waste rubber emulsion comprises 40 to 70 parts by weight of the linearized macromolecular rubber, 0.3 to 10 parts by weight of the first emulsifier, and 30 to 40 parts by weight of water.

4. The water-based non-curable rubber asphalt waterproof coating material as claimed in claim 2, wherein the weight ratio of the emulsified modified asphalt to the waste rubber emulsion is (60-80): (20-40).

5. The aqueous non-curable rubberized asphalt waterproofing coating according to claim 4, wherein the emulsified modified asphalt comprises a modified asphalt, an aqueous solution of a first reinforcing filler, and a second emulsifier, and the second emulsifier is a second anionic emulsifier.

6. The water-based non-curable rubber asphalt waterproof coating material according to claim 5, wherein the emulsified modified asphalt comprises 50 to 70 parts by weight of the modified asphalt, 29 to 47 parts by weight of the aqueous solution of the first reinforcing filler, and 1 to 3 parts by weight of the second emulsifier.

7. The water-based non-curable rubber asphalt waterproof coating material according to claim 6, wherein the modified asphalt comprises 100 parts by weight of base asphalt and 1-5 parts by weight of elastomer polymer.

8. The water-based non-curable rubberized asphalt waterproofing paint according to claim 7, wherein the base asphalt is 70-120 # petroleum asphalt, and the elastomeric polymer is one or more of SBS, SBR and NR.

9. The aqueous non-curing rubberized asphalt waterproofing coating according to claim 5, wherein the first anionic emulsifier and the second anionic emulsifier are respectively selected from one or more of carboxylate, sulfate, sulfonate and phosphate.

10. The water-based non-curing rubber asphalt waterproof coating material as claimed in claim 5, wherein the first reinforcing filler in the aqueous solution of the first reinforcing filler is one or more of nano clay, kaolin, diatomite, bentonite, talc and calcium powder.

11. The water-based non-curable rubber asphalt waterproof coating material according to claim 10, wherein the solid content of the aqueous solution of the first reinforcing filler is 10 to 30%.

12. The aqueous non-curing rubber asphalt waterproofing coating according to any one of claims 1 to 11, wherein the aqueous accelerator solution comprises an aqueous solution of an accelerator and a second reinforcing filler.

13. The aqueous non-curable rubber asphalt waterproofing coating according to claim 12, wherein the aqueous accelerator solution comprises 5 to 15 parts by weight of the accelerator and 85 to 95 parts by weight of the aqueous solution of the second reinforcing filler.

14. The aqueous non-curable rubber asphalt waterproofing coating according to claim 12, wherein the accelerator is one or more selected from the group consisting of magnesium chloride, calcium chloride, aluminum sulfate, aluminum potassium sulfate, poly-phosphorus ferric chloride and poly-phosphorus aluminum chloride.

15. The aqueous non-curing rubber asphalt waterproofing paint according to claim 14, wherein the second reinforcing filler in the aqueous solution of the second reinforcing filler is one or more of nano clay, kaolin, diatomaceous earth, bentonite, talc and calcium powder.

16. A method for preparing the water-based non-curable rubberized asphalt waterproofing paint according to any one of claims 1 to 15, characterized by comprising the steps of: mixing and dispersing the emulsified modified asphalt and the waste rubber emulsion to obtain a component A; preparing a coagulant aqueous solution as component B; wherein the waste rubber emulsion is prepared by the following method:

performing desulfurization degradation on the waste rubber to obtain linear active rubber; wherein the weight percentage content of the linearized molecules in the linearized active rubber is more than or equal to 75 percent;

extracting the linearized macromolecular rubber with the molecular weight more than 10000 from the linearized active rubber;

mixing and emulsifying the linearized macromolecular rubber, a first emulsifier and water to obtain the waste rubber emulsion;

wherein the step of extracting the linearized macromolecular rubber comprises:

wherein the first solvent is one or more of acetone, ethanol, diethyl ether and isopropanol; the second solvent is one or more of hexane, pentane, cyclopentane, dichloromethane, carbon disulfide, ethyl acetate, trichloromethane and cyclohexane;

17. The method of claim 16, wherein the step of mixing and emulsifying the linearized macromolecular rubber, the first emulsifier and water comprises:

preparing the first emulsifier and water into a first soap solution;

adding the supernatant containing the linearized macromolecular rubber into the first soap solution, stirring for 5-60 min at a stirring speed of 100-1000 rpm, and shearing for 5-30 min at a shearing rate of 2000-8000 rpm to obtain an initial product;

and carrying out reduced pressure distillation on the initial product to remove the second solvent in the initial product, so as to obtain the rubber emulsion.

18. The production method according to claim 16, wherein the step of subjecting the waste rubber to desulfurization degradation is performed by one of the following methods:

the method comprises the following steps: in supercritical carbon dioxide, putting the mixture of the rubber powder of the waste rubber and the photocatalyst under ultraviolet light for photocatalytic desulfurization reaction to obtain the linearized active rubber;

the second method comprises the following steps: pretreating the rubber powder of the waste rubber and a regenerating agent at the temperature of 60-150 ℃ for 10-30 min, and standing at the temperature of 50-120 ℃ for 6-36 h to obtain a pretreated product; extruding the pretreated product in a screw extruder, wherein the extrusion temperature is 100-480 ℃, the extrusion pressure is 3-15 Mpa, and the reaction time is 1-15 min, so as to obtain the linearized active rubber;

the third method comprises the following steps: the step of subjecting the waste rubber to devulcanization degradation comprises: placing the rubber powder of the waste rubber into a vertical depolymerizer, adding a solvent, a desulfurization catalyst and a cocatalyst, and then performing desulfurization reaction at the temperature of 160-180 ℃ and under the pressure of 0.5-0.7 MPa to obtain the linearized active rubber; wherein the solvent is paraffin oil and/or solid coumarone, the desulfurization catalyst is phthalic anhydride, and the cocatalyst is formalin and/or resorcinol.

19. The method according to claim 18, wherein the photocatalyst is a composite inorganic photocatalyst.

20. The method of claim 19, wherein the photocatalyst is selected from Co-doped TiO₂、ZrO₂/ZnO composite and ZrO₂/TiO₂One or more of the complexes.

21. The method according to claim 19, wherein the photocatalyst is used in an amount of 0.5 to 3% by weight based on the waste rubber powder.

22. The method of claim 18, wherein the regenerant comprises a softening agent selected from one or more of coal tar, pine tar, tall oil, naphthenic oil, dipentene, paraffin oil, oleic acid, and rosin, and an activating agent selected from one or more of aromatic disulfide, polyalkylphenol sulfide, phenyl mercaptan, and n-butylamine.

23. The method according to claim 22, wherein the weight ratio of the waste rubber powder, the softener and the activator is 100: (5-30): (0.5-5).

24. The method according to any one of claims 16 to 23, wherein the emulsified modified asphalt is prepared by:

heating the matrix asphalt to 160-185 ℃, adding the elastomer polymer, and stirring for 20-40 min at the stirring speed of 1000-3000 rpm to obtain a premix; then, shearing the premix for 5-15 min at the temperature of 160-185 ℃ by using a high-speed shearing emulsifying machine at the shearing speed of 5000-12000 rpm to obtain a sheared substance; finally, stirring the sheared object at the temperature of 160-185 ℃ for 1-4 hours at the stirring speed of 1000-3000 rpm to obtain modified asphalt;

dissolving a first reinforcing filler in water, stirring and standing, and taking supernatant as an aqueous solution of the first reinforcing filler; then adding the second emulsifier into the aqueous solution of the first reinforcing filler to obtain a second soap solution;

and heating the second soap solution to 60-80 ℃, heating the modified asphalt to 150-175 ℃, mixing the second soap solution and the modified asphalt, shearing the mixture in an emulsifying machine, and cooling to obtain the emulsified modified asphalt.

25. The method according to any one of claims 16 to 23, characterized in that the step of preparing the aqueous coagulant solution comprises:

dissolving a second reinforcing filler in water, stirring and standing, and taking supernatant as an aqueous solution of the second reinforcing filler;

mixing a coagulant with an aqueous solution of the second reinforcing filler to obtain the aqueous coagulant solution.