CN114276516B - Method for preparing hard polyurethane foam by using byproducts of waste textile chemical method regeneration process - Google Patents
Method for preparing hard polyurethane foam by using byproducts of waste textile chemical method regeneration process Download PDFInfo
- Publication number
- CN114276516B CN114276516B CN202210041468.XA CN202210041468A CN114276516B CN 114276516 B CN114276516 B CN 114276516B CN 202210041468 A CN202210041468 A CN 202210041468A CN 114276516 B CN114276516 B CN 114276516B
- Authority
- CN
- China
- Prior art keywords
- parts
- reaction
- mass
- ethylene glycol
- polyurethane foam
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Polyurethanes Or Polyureas (AREA)
Abstract
The invention discloses a method for preparing hard polyurethane foam by using byproducts of a chemical method regeneration process of waste textiles, which takes the byproducts of the waste textiles in the chemical method regeneration process as raw materials, and adopts a two-step method of normal pressure azeotropic distillation-reduced pressure distillation to separate high-purity glycol so as to prepare polyester polyol; and then preparing a flame-retardant and ultraviolet-resistant modifier SDS-BTA-LDH by adopting an in-situ assembly strategy, and using the modifier to improve the related performance of the rigid polyurethane foam material. Experiments show that the material not only has low thermal conductivity and excellent mechanical properties, but also shows remarkable flame retardance and ultraviolet resistance, and can be widely applied to the fields of buildings, heat preservation, packaging and the like. The invention effectively solves the technical problem of difficult utilization of byproducts in the glycol alcoholysis-methanol transesterification regeneration process of the waste polyester textiles, and provides a new route for preparing high-performance flame-retardant and ultraviolet-resistant hard polyurethane foam materials.
Description
The technical field is as follows:
the invention relates to the technical field of polyurethane foam material preparation, in particular to a method for preparing rigid polyurethane foam by using a byproduct of a waste textile chemical method regeneration process.
Technical background:
in recent years, the accumulation of waste textiles in China is greatly increased, but the comprehensive utilization rate of the waste textiles is less than 15%, so that not only is a large amount of petroleum resources consumed, but also great harm is caused to the ecological environment in China. Compared with the traditional physical method, the chemical method can realize high-valued closed-loop recycling of the waste polyester textiles. The glycolysis-methanol ester exchange method has the advantages of mild reaction conditions, low equipment requirements, convenience in recycling regenerated monomers and the like, and shows that the glycolysis-methanol ester exchange method is extremely large in reaction conditionThe technical advantages and the industrial development prospect of the method. However, in order to truly realize the complete green and high-valued regeneration of the waste polyester textiles by glycolysis and methanol transesterification, the following problems need to be solved: (1) During the preparation and refining process of regenerated DMT (dimethyl terephthalate), a large amount of byproducts containing ethylene glycol as a main component and a small amount of diethylene glycol, methanol, BHET (ethylene terephthalate), organic pigments, alcoholysis and ester exchange catalysts are generated, and serious secondary environmental pollution is caused if the byproducts cannot be reasonably utilized. (2) The ethylene glycol in the by-product can be used as an effective raw material for developing a series of high-use-value products. However, such by-products contain a large amount of impurities, and the performance of downstream products directly prepared from the by-products as raw materials is difficult to stably regulate and control. In particular K contained in the by-product + 、Na + Alkali metal ions easily cause neutralization of acidic active sites on the surface of the catalyst in the ethylene glycol polymerization process, so that catalyst poisoning is caused, and development of downstream high-valued products of ethylene glycol in byproducts is extremely difficult. Therefore, it is highly desirable to develop a technique for efficiently purifying ethylene glycol and to find an effective method suitable for the high-value utilization of ethylene glycol as a by-product.
The rigid polyurethane foam material can be prepared by taking ethylene glycol as a raw material, has excellent mechanical property, chemical corrosion resistance and sound insulation property, and can be widely applied to the fields of furniture, buildings, automotive interiors and the like. However, polyurethane foams have low density, large specific surface area and a limiting oxygen index of only 18%, so that they are thermally unstable and are very liable to ignite. In addition, under the irradiation of sunlight, the high-energy ultraviolet light of the polyurethane material easily causes the internal thermal and photo-oxidative reactions of the material, so that the molecular chain of the polyurethane is broken, and the service life of the material is greatly shortened. Therefore, the flame retardation and ultraviolet resistance modification of the rigid polyurethane foam material become one of the research hotspots. However, when the flame retardant and ultraviolet resistant modifier is directly added into the polyurethane material, the compatibility between the matrix and the additive is poor, so that not only a good modification effect cannot be obtained, but also the mechanical properties of the material are reduced. In addition, the material added with the halogen and phosphorus flame retardant can release a large amount of toxic smoke in use, and can cause great harm to the environment and human bodies. Therefore, a green and efficient modifier for improving the flame retardant and ultraviolet resistance of the rigid polyurethane foam material is needed to be found.
Layered Double Hydroxides (LDH) are typical anionic Layered compounds, wherein the framework of a plate layer is composed of divalent and trivalent metal Hydroxides, the plate layer is electropositive and has a large number of hydroxyl groups on the surface, and compensating anions and water molecules between layers are combined with a main plate layer in the forms of hydrogen bonds, electrostatic forces, ionic bonds and the like. The interchangeability of anions among LDH layers not only enables the modifier to be organically combined with LDH, but also provides an advantageous condition for the modifier to be compounded with a polymer matrix. In addition, the LDH binds water and CO through release interlayers when the polymer/LDH composite material meets high temperature 2 And the function of diluting oxygen and reducing the surface temperature of the polymer is realized. In addition, the metal hydroxide of the LDH plate layer and the polymer generate special catalytic reaction in the combustion degradation process, and a compact carbon layer is formed on the surface of the composite material, so that external heat and oxygen are effectively prevented from permeating into the polymer, and the mass loss rate of the polymer during thermal degradation is slowed down. Therefore, the LDH can be used as a modifier to effectively improve the flame retardant and ultraviolet resistance of the rigid polyurethane foam material.
Based on the method, the byproducts of the glycolysis-methanol transesterification process of the waste polyester textiles are used as raw materials, high-purity ethylene glycol is prepared by a high-efficiency separation technology, the ethylene glycol is used as the raw material to prepare the hard polyurethane foam material, and the LDH and the ultraviolet absorber are combined to improve the flame retardant and ultraviolet resistance of the material, so that the method has important application value.
Disclosure of Invention
The invention provides a method for preparing rigid polyurethane foam by using byproducts of a waste textile chemical method regeneration process, which comprises the steps of taking the byproducts (mainly ethylene glycol) generated in a glycol alcoholysis-methanol transesterification recovery process of waste polyester textiles as raw materials, obtaining high-purity ethylene glycol through a two-step method of normal-pressure azeotropic rectification-reduced pressure distillation, then reacting the high-purity ethylene glycol with dibasic acid to generate polyester polyol, innovatively adopting an in-situ assembly strategy to prepare a flame-retardant and ultraviolet-resistant modifier SDS-BTA-LDH, and then synthesizing the halogen-free flame-retardant and ultraviolet-resistant rigid polyurethane foam material by adopting a one-step method through the polyester polyol, a catalyst, isocyanate, the SDS-BTA-LDH, a foaming agent, a cross-linking agent and a chain extender. The method has low preparation cost and simple operation condition, effectively solves the problem of difficult recycling of byproducts in the preparation and refining processes of the regenerated DMT, provides a new raw material route for the preparation of flame-retardant and ultraviolet-resistant rigid polyurethane foam materials, and powerfully promotes the development of completely green and high-valued regeneration of the glycol alcoholysis-methanol transesterification process of the waste polyester textiles.
In order to achieve the purpose, the invention adopts the following technical scheme:
a method for preparing rigid polyurethane foam by using byproducts of a chemical method regeneration process of waste textiles comprises the following steps:
(1) Preparation of polyester polyol:
feeding the mixed solution of glycol and dibasic acid into a reaction kettle filled with nitrogen protection, carrying out esterification reaction under the condition of full stirring, removing water after the reaction is finished, adding a p-toluenesulfonic acid catalyst to carry out first-stage polycondensation reaction, reducing the system temperature, vacuumizing, and then carrying out second-stage polycondensation reaction to finally obtain polyester polyol;
(2) Preparation of self-assembled modifier SDS-BTA-LDH:
slowly adding a quantitative soluble divalent and trivalent metal salt solution into a mixed solution of sodium dodecyl sulfate and a benzotriazole ultraviolet absorbent, adding a proper amount of alkaline solution into the mixed solution, carrying out hydrothermal reaction under the condition of continuous stirring, filtering to obtain a product after the reaction is finished, washing with a large amount of distilled water, and finally drying in vacuum to obtain self-assembled modified SDS-BTA-LDH;
(3) Preparing a flame-retardant and ultraviolet-resistant hard polyurethane foam material:
adding the metered polyester polyol, isocyanate, SDS-BTA-LDH, a chain extender, a cross-linking agent, a foaming agent and a catalyst into a container together, uniformly stirring for reaction, then injecting the mixture into a mold for foaming, and finally drying the foamed material in the mold to obtain the hard polyurethane foam material.
In the step (1), the glycol is a purified product containing a glycol byproduct obtained in a chemical method regeneration process of the waste textiles.
The method for purifying the ethylene glycol comprises the following steps: feeding the ethylene glycol-containing by-product and the entrainer into an azeotropic distillation tower, refining the ethylene glycol by adopting an intermittent distillation mode, distilling an azeotrope formed by the ethylene glycol and the entrainer from the tower top after the distillation is finished, cooling the azeotrope by a condenser, feeding the cooled azeotrope into a phase separator, feeding the entrainer-containing phase on the upper layer back to the distillation tower, feeding the glycol phase containing a small amount of impurities on the lower layer into a reduced pressure distillation tower for impurity separation, and finally obtaining the distillate at the tower top of the distillation tower, namely the high-purity ethylene glycol.
The entrainer is any one of toluene, n-butyl ether and m-xylene; the mass charge ratio of the ethylene glycol-containing by-product to the entrainer is 10-30:1, the operating temperature of the azeotropic distillation tower is 110-130 ℃, the operating pressure is 0.1-0.3MPa, and the reflux ratio is 1-15; the operating pressure of the reduced pressure distillation tower is 5-12KPa.
In the step (1), the dibasic acid is any one of adipic acid, terephthalic acid and isophthalic acid; the mass charge ratio of the glycol to the dibasic acid in the esterification reaction is 0.5-5:1, the esterification reaction temperature is 110-200 ℃; the addition amount of the p-toluenesulfonic acid catalyst in the first-stage polycondensation reaction accounts for 0.03-0.5% of the total feed ratio, the reaction temperature is 200-300 ℃, the reaction time is 2-5h, the system temperature is reduced to 50-80 ℃ after the first-stage polycondensation reaction is finished, the second-stage polycondensation reaction is carried out after the system acid value is reduced to 10-30mgKOH and the system is vacuumized to 500-800mmHg, and the reaction is finished when the system acid value is 1-10mgKOH, so that the polyester polyol can be obtained.
The divalent cation in the soluble divalent and trivalent metal salt solution in the step (2) is Cu 2+ 、Zn 2+ 、Ni 2+ 、Mg 2+ Wherein the trivalent cation is Fe 3+ 、Al 3+ Any one of the above; the anion in the soluble divalent metal salt and the soluble trivalent metal salt is NO 3 - 、SO 4 2- Any one of(ii) a The benzotriazole ultraviolet absorbent is any one of (2- (2-hydroxy-5-methylphenyl) benzotriazole, 2- (2-hydroxy-3-tert-butyl-5-methylphenyl) -5-chlorobenzotriazole and 2- (2-hydroxy-3,5-di-tert-phenyl) -5-chlorobenzotriazole, and the alkaline substance is any one of urea, ammonia water or sodium hydroxide.
The preparation of the self-assembly modified SDS-BTA-LDH in the step (2) takes 100 parts by mass of divalent metal salt as a reference, and the feeding amount of the other raw materials is as follows: 20-70 parts of trivalent metal salt, 10-30 parts of sodium dodecyl benzene sulfonate, 20-40 parts of benzotriazole ultraviolet absorbent and 50-200 parts of alkaline substance; the temperature of the hydrothermal reaction is 60-110 ℃, the time is 10-24h, and the pH value of the reaction system is 7-10.
In the preparation process of the hard polyurethane foam material in the step (3), 100 parts by mass of polyester polyol is taken as a reference, and the feeding amount of the other raw materials is as follows: 0.5-5 parts of SDS-BTA-LDH, 0.1-3 parts of catalyst, 90-120 parts of isocyanate, 1-10 parts of cross-linking agent, 0.1-1 part of foaming agent and 1-10 parts of chain extender, wherein the reaction temperature for preparing the hard polyurethane foam material is 20-50 ℃, the pressure is 0.1-0.5MPa, the preheating temperature of a die is 50-80 ℃, the drying temperature of the foam material is 90-150 ℃, and the drying time is 2-5h.
The isocyanate in the step (3) is any one of 4,4-diphenyl isocyanate, polymethylene polyphenyl polyisocyanate and toluene diisocyanate; the chain extender is any one of 1,3-propylene glycol, 1,6-hexanediol and neopentyl glycol; the cross-linking agent is any one of trimethylolpropane, castor oil and pentaerythritol; the foaming agent comprises any one of cyclopentane, n-pentane and dichloromethane; the catalyst is any one of triethylene diamine, dimethyl cyclohexylamine, stannous octoate and dibutyltin dilaurate.
Compared with the prior art, the invention has the following advantages:
(1) The method adopts a strategy of a two-step method of normal-pressure azeotropic distillation and reduced-pressure distillation, and successfully utilizes the byproduct of the waste polyester textile glycol alcoholysis-methanol ester exchange regeneration process to prepare the high-purity glycol, so that the high-purity glycol can be used for preparing downstream high-performance products, and the greenness and resource utilization of the regeneration process are improved.
(2) The halogen-free flame retardant modifier LDH is adopted to effectively improve the flame retardant property of the polyurethane material. In addition, by utilizing the exchangeable characteristic of anions among LDH layers, the ultraviolet light absorbent and the LDH are successfully combined, and the self-assembly modifier SDS-BTA-LDH is uniformly dispersed in the polyurethane, so that the ultraviolet resistance of the polyurethane foam material is effectively improved.
(3) Compared with the traditional preparation method of the polyurethane material, the halogen-free flame-retardant and ultraviolet-resistant polyurethane/LDH hard foam material is prepared by adopting an in-situ polymerization strategy, and the material can be widely applied to the fields of buildings, heat preservation, pipelines and the like due to excellent flame retardance, ultraviolet resistance and mechanical properties, so that high-value utilization of byproducts in a regeneration process is effectively realized, and a new raw material route is provided for preparing a high-performance polyurethane material.
Drawings
FIG. 1 is a diagram of the morphology of the self-assembled SDS-BTA-LDH of example 1.
FIG. 2 is an X-ray diffraction pattern of the self-assembled SDS-BTA-LDH of example 1.
Fig. 3 shows the results of the uv absorbance test performance of the materials prepared in examples 1,3, 5, 7, and 9.
Detailed Description
The invention is further described with reference to the accompanying drawings and the detailed description below:
example 1
(1) The ethylene glycol containing by-product was reacted with toluene according to a 10:1, under the conditions of 0.1MPa and 110 ℃, controlling the condensation reflux ratio to be 1, adopting an intermittent rectification mode to ensure that ethylene glycol and toluene form an azeotrope to be distilled off from the top of the tower, cooling the azeotrope by a condenser and then sending the cooled azeotrope into a phase separator, sending the upper layer of the azeotrope containing toluene to the rectification tower, sending the lower layer of the ethylene glycol phase containing a small amount of impurities into a reduced pressure distillation tower, separating light component impurities from the top of the tower under the operating pressure of 5KPa, and obtaining high-purity ethylene glycol from the bottom of the tower.
(2) Mixing high-purity ethylene glycol and adipic acid according to the weight ratio of 0.5: feeding the alkyd of 1 into a reaction kettle with nitrogen protection and stirring, esterifying at the reaction temperature of 110 ℃, removing water after reaction, adding a p-toluenesulfonic acid catalyst accounting for 0.03 percent of the total feeding amount to perform a first-stage polycondensation reaction, reacting at the temperature of 200 ℃ for 4 hours, then reducing the temperature to 50 ℃, vacuumizing when the acid value reaches 10mgKOH, performing a second-stage esterification reaction under the vacuum degree of 500mmHg, and finishing the reaction when the acid value is less than 1mgKOH to obtain the polyester polyol.
(3) CuSO was added to 5000 parts by mass of distilled water based on 100 parts by mass of a divalent metal salt 4 (100 parts by mass) and Al 2 (SO 4 ) 3 (20 parts by mass), sodium dodecylbenzenesulfonate (10 parts by mass), 2- (2-hydroxy-5-methylphenyl) benzotriazole (20 parts by mass), and urea (50 parts by mass). And (2) carrying out hydrothermal reaction for 10h under the condition of continuously stirring at 60 ℃ and pH =7, filtering after the reaction is finished to obtain a product, washing the product by using a large amount of distilled water, and finally drying the product for 12h in vacuum to obtain the self-assembly modifier SDS-BTA-LDH.
(4) Adding 100 parts by mass of polyester polyol, SDS-BTA-LDH (0.5 part by mass), 0.4 part by mass of catalyst (triethylene diamine), 92 parts by mass of isocyanate (4,4-diphenyl isocyanate (MDI)), chain extender (1,3-propylene glycol (1,3-PDO)), 1.8 parts by mass of cross-linking agent (trimethylolpropane (TMP)) and 0.16 part by mass of foaming agent (cyclopentane) into a reaction vessel, stirring at 20 ℃ and 0.1MPa for pre-reaction, injecting the mixture into a mold with the preheating temperature of 50 ℃ for foaming, and finally drying the mold at the temperature of 90 ℃ for 2 hours to obtain the rigid polyurethane foam material.
Example 2
(1) The ethylene glycol containing by-product was reacted with n-butyl ether according to 12:1, under the condition of 0.13MPa and 115 ℃, controlling the condensation reflux ratio to be 3, adopting an intermittent rectification mode to ensure that ethylene glycol and n-butyl ether form an azeotrope to be distilled out of the tower top, cooling the azeotrope by a condenser and then sending the cooled azeotrope into a phase separator, sending the upper-layer azeotrope containing the n-butyl ether back to the rectification tower, sending the lower-layer ethylene glycol phase containing a small amount of impurities into a reduced pressure distillation tower, separating light-component impurities from the tower top under the operating pressure of 5.4KPa, and obtaining high-purity ethylene glycol from the tower bottom.
(2) Mixing high-purity ethylene glycol and adipic acid according to the weight ratio of 0.8: feeding the alkyd of 1 into a reaction kettle with nitrogen protection and stirring, esterifying at the reaction temperature of 116 ℃, removing water after reaction, adding a p-toluenesulfonic acid catalyst accounting for 0.09 percent of the total feeding amount to perform a first-stage polycondensation reaction, reacting at the temperature of 220 ℃ for 4 hours, reducing the temperature to 53 ℃, vacuumizing when the acid value reaches 13mgKOH, performing a second-stage esterification reaction at the vacuum degree of 530mmHg, and finishing the reaction when the acid value is less than 1.7mgKOH to obtain the polyester polyol.
(3) CuSO is added to 5000 parts by mass of distilled water based on 100 parts by mass of a divalent metal salt 4 (100 parts by mass), al 2 (SO 4 ) 3 (30 parts by mass), sodium dodecylbenzenesulfonate (15 parts by mass), 2- (2-hydroxy-3-tert-butyl-5-methylphenyl) -5-chlorobenzotriazole (22 parts by mass), and urea (70 parts by mass). And (2) continuously stirring at 70 ℃ under the condition of pH =7.5 to carry out hydrothermal reaction for 12h, filtering after the reaction is finished to obtain a product, washing the product by using a large amount of distilled water, and finally drying the product in vacuum for 12h to obtain the self-assembly modifier SDS-BTA-LDH.
(4) Adding SDS-BTA-LDH (1 part by mass), a catalyst (triethylene diamine) 0.8 part by mass, isocyanate (4,4-diphenyl isocyanate (MDI)) 97 parts by mass, a chain extender (1,6-Hexanediol (HDO)) 2.1 parts by mass, a cross-linking agent (castor oil) 2.3 parts by mass and a foaming agent (cyclopentane) 0.21 part by mass into a reaction container, stirring at 23 ℃ and 0.13MPa for pre-reaction, injecting the mixture into a mold with a preheating temperature of 54 ℃ for foaming, drying the mold at 95 ℃ for 2.5 hours, and obtaining the rigid polyurethane foam material.
Example 3
(1) The ethylene glycol containing by-product was reacted with meta-xylene according to 14:1, under the condition of 0.16MPa and 118 ℃, controlling the condensation reflux ratio to be 5, adopting an intermittent rectification mode to ensure that ethylene glycol and m-xylene form an azeotrope to be distilled off from the top of the tower, cooling the azeotrope by a condenser and then sending the cooled azeotrope into a phase separator, sending the m-xylene entrainer component in the upper layer back to the rectification tower, sending the ethylene glycol phase containing a small amount of impurities in the lower layer into a reduced pressure distillation tower, separating light component impurities from the top of the tower under the operating pressure of 5.8KPa, and obtaining high-purity ethylene glycol from the bottom of the tower.
(2) High-purity ethylene glycol and terephthalic acid are mixed according to the weight ratio of 1.2: feeding the alkyd of 1 into a reaction kettle with nitrogen protection and stirring, esterifying at the reaction temperature of 123 ℃, removing water after reaction, adding a p-toluenesulfonic acid catalyst accounting for 0.12 percent of the total feeding amount to perform a first-stage polycondensation reaction, reacting at the temperature of 235 ℃ for 4 hours, reducing the temperature to 57 ℃, vacuumizing when the acid value reaches 15mgKOH, performing a second-stage esterification reaction under the vacuum degree of 570mmHg, and finishing the reaction when the acid value is less than 2mgKOH to obtain the polyester polyol.
(3) Adding ZnSO into 5000 parts by mass of distilled water based on 100 parts by mass of divalent metal salt 4 (100 parts by mass) and Fe 2 (SO 4 ) 3 (30 parts by mass), sodium dodecylbenzenesulfonate (17 parts by mass), 2- (2-hydroxy-3-tert-butyl-5-methylphenyl) -5-chlorobenzotriazole (24 parts by mass), and urea (95 parts by mass). And (2) continuously stirring at 70 ℃ under the condition of pH =8 to perform hydrothermal reaction for 14h, filtering after the reaction is finished to obtain a product, washing the product by using a large amount of distilled water, and finally performing vacuum drying for 12h to obtain the self-assembly modifier SDS-BTA-LDH.
(4) Adding 1.3 parts by mass of SDS-BTA-LDH, 1.12 parts by mass of a catalyst (dimethylcyclohexylamine), 103 parts by mass of isocyanate (4,4-diphenyl isocyanate (MDI)), 2.6 parts by mass of a chain extender (1,6-Hexanediol (HDO)), 2.8 parts by mass of a cross-linking agent (castor oil) and 0.29 part by mass of a foaming agent (cyclopentane) into a reaction vessel, stirring under the conditions of 27 ℃ and 0.17MPa for pre-reaction, injecting the pre-reaction vessel into a mold with the preheating temperature of 58 ℃ for foaming, and finally drying the mold at the temperature of 100 ℃ for 3 hours to obtain the rigid polyurethane foam material.
Example 4
(1) The ethylene glycol containing by-product was reacted with toluene according to 16:1, under the conditions of 0.18MPa and 122 ℃, controlling the condensation reflux ratio to be 7, adopting an intermittent rectification mode to ensure that ethylene glycol and toluene form an azeotrope to be distilled off from the top of the tower, cooling the azeotrope by a condenser and then sending the cooled azeotrope into a phase separator, sending the upper layer of an entrainer containing toluene back to the rectification tower, sending the lower layer of an ethylene glycol phase containing a small amount of impurities into a reduced pressure distillation tower, separating light component impurities from the top of the tower under the operating pressure of 6.3KPa, and obtaining high-purity ethylene glycol from the bottom of the tower.
(2) High-purity ethylene glycol and terephthalic acid are mixed according to the weight ratio of 1.9: feeding the alkyd with the feeding ratio of 1 into a reaction kettle with nitrogen protection and stirring, esterifying at the reaction temperature of 128 ℃, removing water after reaction, adding a p-toluenesulfonic acid catalyst accounting for 0.17 percent of the total feeding amount to perform a first-stage polycondensation reaction, reacting at the temperature of 245 ℃ for 4 hours, then reducing the temperature to 62 ℃, vacuumizing when the acid value reaches 18mgKOH, performing a second-stage esterification reaction under the vacuum degree of 610mmHg, and finishing the reaction when the acid value is less than 2.4mgKOH to obtain the polyester polyol.
(3) Mg (NO) was added to 5000 parts by mass of distilled water based on 100 parts by mass of a divalent metal salt 3 ) 2 (100 parts by mass), fe (NO) 3 ) 3 (25 parts by mass), sodium dodecylbenzenesulfonate (20 parts by mass), 2- (2-hydroxy-5-methylphenyl) benzotriazole (26 parts by mass), and sodium hydroxide (95 parts by mass). And (2) continuously stirring at 75 ℃ under the condition of pH =8.5 to carry out hydrothermal reaction for 14h, filtering after the reaction is finished to obtain a product, washing the product by using a large amount of distilled water, and finally drying the product in vacuum for 12h to obtain the self-assembly modifier SDS-BTA-LDH.
(4) Adding SDS-BTA-LDH (2.4 parts by mass), a catalyst (stannous octoate) 1.53 parts by mass, isocyanate (polymethylene polyphenyl polyisocyanate (PAPI)) 109 parts by mass, a chain extender (1,6-Hexanediol (HDO)) 3.1 parts by mass, a cross-linking agent (castor oil) 3.1 parts by mass and a foaming agent (n-pentane) 0.35 parts by mass into a reaction container, stirring at 33 ℃ and 0.23MPa for pre-reaction, injecting the mixture into a mold with the preheating temperature of 62 ℃ for foaming, and finally drying the mold at the temperature of 115 ℃ for 3.5 hours to obtain the hard polyurethane foam material.
Example 5
(1) The ethylene glycol containing by-product was reacted with n-butyl ether according to 18:1, under the conditions of 0.2MPa and 125 ℃, controlling the condensation reflux ratio to be 9, adopting an intermittent rectification mode to ensure that ethylene glycol and toluene form an azeotrope to be distilled off from the top of the tower, cooling the azeotrope by a condenser and then sending the cooled azeotrope into a phase separator, sending the upper layer of the azeotrope containing toluene back to the rectification tower, sending the lower layer of the ethylene glycol phase containing a small amount of impurities into a reduced pressure distillation tower, separating light component impurities from the top of the tower under the operating pressure of 6.6KPa, and obtaining high-purity ethylene glycol from the bottom of the tower.
(2) High-purity ethylene glycol and terephthalic acid are mixed according to the ratio of 2.2: feeding the alkyd of 1 into a reaction kettle with nitrogen protection and stirring, esterifying at the reaction temperature of 145 ℃, removing water after reaction, adding a p-toluenesulfonic acid catalyst accounting for 0.22 percent of the total feeding amount to perform a first-stage polycondensation reaction, reacting at the temperature of 255 ℃ for 4 hours, reducing the temperature to 68 ℃, vacuumizing when the acid value reaches 21mgKOH, performing a second-stage esterification reaction at the vacuum degree of 650mmHg, and finishing the reaction when the acid value is less than 3mgKOH to obtain the polyester polyol.
(3) CuSO was added to 5000 parts by mass of distilled water based on 100 parts by mass of a divalent metal salt 4 (100 parts by mass) and Fe 2 (SO 4 ) 3 (35 parts by mass), sodium dodecylbenzenesulfonate (23 parts by mass), 2- (2-hydroxy-3-tert-butyl-5-methylphenyl) -5-chlorobenzotriazole (28 parts by mass), and aqueous ammonia (105 parts by mass). And (2) carrying out hydrothermal reaction for 16h under the conditions of 80 ℃ and pH =9 by continuous stirring, filtering after the reaction is finished to obtain a product, washing the product by using a large amount of distilled water, and finally drying the product for 12h in vacuum to obtain the self-assembly modifier SDS-BTA-LDH.
(4) Adding SDS-BTA-LDH (2.8 parts by mass), a catalyst (stannous octoate) 1.92 parts by mass, isocyanate (polymethylene polyphenyl polyisocyanate (PAPI)) 113 parts by mass, a chain extender (1,6-Hexanediol (HDO)) 3.6 parts by mass, a cross-linking agent (pentaerythritol) 3.8 parts by mass and a foaming agent (n-pentane) 0.42 parts by mass into a reaction container, stirring at 36 ℃ and 0.26MPa for pre-reaction, injecting the mixture into a mold with the preheating temperature of 66 ℃ for foaming, and finally drying the mold at the temperature of 120 ℃ for 4 hours to obtain the rigid polyurethane foam material.
Example 6
(1) The ethylene glycol-containing by-product is reacted with m-xylene in a 20:1, under the condition of 0.22MPa and 116 ℃, controlling the condensation reflux ratio to be 11, adopting an intermittent rectification mode to ensure that ethylene glycol and m-xylene form an azeotrope to be distilled off from the top of the tower, cooling the azeotrope by a condenser and then sending the cooled azeotrope into a phase separator, sending the m-xylene entrainer component in the upper layer back to the rectification tower, sending the ethylene glycol phase containing a small amount of impurities in the lower layer into a reduced pressure distillation tower, separating light component impurities from the top of the tower under the operating pressure of 6.9KPa, and obtaining high-purity ethylene glycol from the bottom of the tower.
(2) High-purity ethylene glycol and isophthalic acid are mixed according to the weight ratio of 2.5: feeding the alkyd of 1 into a reaction kettle with nitrogen protection and stirring, esterifying at the reaction temperature of 148 ℃, removing water after reaction, adding a p-toluenesulfonic acid catalyst accounting for 0.28 percent of the total feeding amount to perform a first-stage polycondensation reaction, reacting at the temperature of 265 ℃ for 4 hours, then reducing the temperature to 72 ℃, vacuumizing when the acid value reaches 25mgKOH, performing a second-stage esterification reaction at the vacuum degree of 670mmHg, and finishing the reaction when the acid value is less than 3.5mgKOH to obtain the polyester polyol.
(3) NiSO is added into distilled water in an amount of 5000 parts by mass based on 100 parts by mass of a divalent metal salt 4 (100 parts by mass) and Al 2 (SO 4 ) 3 (35 parts by mass), sodium dodecylbenzenesulfonate (25 parts by mass), 2- (2-hydroxy-3,5-di-tert-phenyl) -5-chlorobenzotriazole (30 parts by mass), urea (115 parts by mass). And (2) carrying out hydrothermal reaction for 16h under the conditions of 85 ℃ and pH =9 by continuous stirring, filtering after the reaction is finished to obtain a product, washing the product by using a large amount of distilled water, and finally drying the product for 12h in vacuum to obtain the self-assembly modifier SDS-BTA-LDH.
(4) Based on 100 parts by mass of polyester polyol, adding SDS-BTA-LDH (3.2 parts by mass), a catalyst (dibutyltin dilaurate) 2.13 parts by mass, isocyanate (toluene diisocyanate (TDI)) 112 parts by mass, a chain extender (neopentyl glycol (NPG)) 4.1 parts by mass, a cross-linking agent (pentaerythritol) 4.2 parts by mass and a foaming agent (dichloromethane) 0.52 part by mass into a reaction vessel, stirring at 38 ℃ and 0.28MPa for pre-reaction, injecting the mixture into a mold with a preheating temperature of 68 ℃ for foaming, and drying the mold at 125 ℃ for 4.5 hours to obtain the rigid polyurethane foam material.
Example 7
(1) The ethylene glycol containing by-product was reacted with toluene according to 22:1, under the conditions of 0.25MPa and 123 ℃, controlling the condensation reflux ratio to be 13, adopting an intermittent rectification mode to ensure that ethylene glycol and toluene form an azeotrope to be distilled off from the top of the tower, cooling the azeotrope by a condenser and then sending the cooled azeotrope into a phase separator, sending the upper layer of the azeotrope containing toluene to the rectification tower, sending the lower layer of the ethylene glycol phase containing a small amount of impurities into a reduced pressure distillation tower, separating light component impurities from the top of the tower under the operating pressure of 7.3KPa, and obtaining high-purity ethylene glycol from the bottom of the tower.
(2) High-purity ethylene glycol and isophthalic acid are mixed according to the ratio of 2.8: feeding the alkyd with the feeding ratio of 1 into a reaction kettle with nitrogen protection and stirring, esterifying at the reaction temperature of 153 ℃, removing water after reaction, adding a p-toluenesulfonic acid catalyst accounting for 0.31 percent of the total feeding amount to perform a first-stage polycondensation reaction, reacting at the temperature of 275 ℃ for 4 hours, then reducing the temperature to 75 ℃, vacuumizing when the acid value reaches 27mgKOH, performing a second-stage esterification reaction under the vacuum degree of 730mmHg, and finishing the reaction when the acid value is less than 4mgKOH to obtain the polyester polyol.
(3) Based on 100 parts by mass of divalent metal salt, mgSO was added to 5000 parts by mass of distilled water 4 (100 parts by mass), al 2 (SO 4 ) 3 42 parts by mass, 26 parts by mass of sodium dodecylbenzenesulfonate, 32 parts by mass of 2- (2-hydroxy-5-methylphenyl) benzotriazole and 130 parts by mass of urea. Continuously stirring at 90 deg.C and pH =9.5 for hydrothermal reaction for 18h, filtering after the reaction is finished to obtain product, washing with distilled water, and vacuum washingAnd air-drying for 12h to obtain the self-assembly modifier SDS-BTA-LDH.
(4) Taking 100 parts by mass of polyester polyol as a reference, adding 2.14 parts by mass of SDS-BTA-LDH (4.2 parts by mass), 2.14 parts by mass of a catalyst (dibutyltin dilaurate), 110 parts by mass of isocyanate (toluene diisocyanate (TDI)), 5.3 parts by mass of a chain extender (neopentyl glycol (NPG)), 4.9 parts by mass of a cross-linking agent (pentaerythritol) and 0.59 part by mass of a foaming agent (dichloromethane) into a reaction vessel, stirring at 42 ℃ and 0.32MPa for pre-reaction, injecting the mixture into a mold with the preheating temperature of 70 ℃ for foaming, and finally drying the mold at 130 ℃ for 5 hours to obtain the rigid polyurethane foam material.
Example 8
(1) The ethylene glycol containing by-product was reacted with n-butyl ether according to a 24:1, under the condition of 0.28MPa and 128 ℃, controlling the condensation reflux ratio to be 15, adopting an intermittent rectification mode to ensure that ethylene glycol and n-butyl ether form an azeotrope to be distilled out from the top of the tower, cooling the azeotrope by a condenser and then sending the cooled azeotrope into a phase separator, sending the upper-layer azeotrope containing the n-butyl ether back to the rectification tower, sending the lower-layer ethylene glycol phase containing a small amount of impurities into a reduced pressure distillation tower, separating light-component impurities from the top of the tower under the operating pressure of 7.8KPa, and obtaining high-purity ethylene glycol from the bottom of the tower.
(2) High-purity ethylene glycol and adipic acid are mixed according to the ratio of 3.3: feeding the alkyd with the feeding ratio of 1 into a reaction kettle with nitrogen protection and stirring, esterifying at the reaction temperature of 162 ℃, removing water after reaction, adding a p-toluenesulfonic acid catalyst accounting for 0.35 percent of the total feeding amount to perform a first-stage polycondensation reaction, reacting at the temperature of 280 ℃ for 4 hours, then reducing the temperature to 77 ℃, vacuumizing when the acid value reaches 28mgKOH, performing a second-stage esterification reaction under the vacuum degree of 750mmHg, and finishing the reaction when the acid value is less than 5.5mgKOH to obtain the polyester polyol.
(3) Adding ZnSO into 5000 parts by mass of distilled water based on 100 parts by mass of divalent metal salt 4 (100 parts by mass), fe 2 (SO 4 ) 3 (50 parts by mass), sodium dodecylbenzenesulfonate (27 parts by mass), 2- (2-hydroxy-3-tert-butyl-5-methylphenyl) -5-chlorobenzoTriazole (34 parts by mass), and urea (150 parts by mass). And (2) carrying out hydrothermal reaction for 19h under the conditions of 95 ℃ and pH =9.5 by continuous stirring, filtering after the reaction is finished to obtain a product, washing the product by using a large amount of distilled water, and finally drying the product for 12h in vacuum to obtain the self-assembly modifier SDS-BTA-LDH.
(4) Adding SDS-BTA-LDH (4.3 parts by mass), a catalyst (triethylene diamine) 2.35 parts by mass, isocyanate (4,4-diphenyl isocyanate (MDI)) 106 parts by mass, a chain extender (1,6-Hexanediol (HDO)) 5.9 parts by mass, a cross-linking agent (castor oil) 5.4 parts by mass and a foaming agent (n-pentane) 0.63 part by mass into a reaction vessel, stirring under the conditions of 44 ℃ and 0.36MPa for pre-reaction, injecting the pre-reaction vessel into a mold with the preheating temperature of 72 ℃ for foaming, and finally drying the mold at the temperature of 135 ℃ for 3.5 hours to obtain the rigid polyurethane foam material.
Example 9
(1) The ethylene glycol containing by-product is reacted with meta-xylene according to a 26:1, under the conditions of 0.3MPa and 130 ℃, controlling the condensation reflux ratio to be 3, adopting an intermittent rectification mode to ensure that ethylene glycol and m-xylene form an azeotrope to be distilled off from the top of the tower, cooling the azeotrope by a condenser and then sending the cooled azeotrope into a phase separator, sending the m-xylene entrainer component in the upper layer back to the rectification tower, sending the ethylene glycol phase containing a small amount of impurities in the lower layer into a reduced pressure distillation tower, separating light component impurities from the top of the tower under the operating pressure of 8.4KPa, and obtaining high-purity ethylene glycol from the bottom of the tower.
(2) Mixing high-purity ethylene glycol and adipic acid according to the weight ratio of 3.7: feeding the alkyd of 1 into a reaction kettle provided with nitrogen protection and stirring, esterifying at the reaction temperature of 175 ℃, removing water after reaction, adding a p-toluenesulfonic acid catalyst accounting for 0.43 percent of the total feeding amount to perform a first-stage polycondensation reaction, reacting at the temperature of 290 ℃ for 4 hours, reducing the temperature to 80 ℃, vacuumizing when the acid value reaches 28mgKOH, performing a second-stage esterification reaction under the vacuum degree of 760mmHg, and finishing the reaction when the acid value is less than 6.5mgKOH to obtain the polyester polyol.
(3) Steaming at 5000 parts by mass based on 100 parts by mass of divalent metal saltAdding FeSO into distilled water 4 (100 parts by mass) and Fe 2 (SO 4 ) 3 (55 parts by mass), sodium dodecylbenzenesulfonate (27 parts by mass), 2- (2-hydroxy-3,5-di-tert-phenyl) -5-chlorobenzotriazole (36 parts by mass), and urea (160 parts by mass). And (2) carrying out hydrothermal reaction for 19h under the conditions of 95 ℃ and pH =9.5 by continuous stirring, filtering after the reaction is finished to obtain a product, washing the product by using a large amount of distilled water, and finally drying the product for 12h in vacuum to obtain the self-assembly modifier SDS-BTA-LDH.
(4) Adding 4.6 parts by mass of SDS-BTA-LDH, 2.54 parts by mass of a catalyst (dimethylcyclohexylamine), 115 parts by mass of isocyanate (toluene diisocyanate (TDI)), 6.5 parts by mass of a chain extender (neopentyl glycol (NPG)), 6.7 parts by mass of a cross-linking agent (pentaerythritol) and 0.76 part by mass of a foaming agent (dichloromethane) into a reaction vessel, stirring at 46 ℃ and 0.38MPa for pre-reaction, injecting the mixture into a mold with a preheating temperature of 76 ℃ for foaming, and drying the mold at 140 ℃ for 3 hours to obtain the rigid polyurethane foam material.
Example 10
(1) The ethylene glycol containing by-product was mixed with m-xylene according to a 30:1, under the conditions of 0.19MPa and 130 ℃, controlling the condensation reflux ratio to be 12, adopting an intermittent rectification mode to ensure that ethylene glycol and m-xylene form an azeotrope to be distilled off from the top of the tower, cooling the azeotrope by a condenser and then sending the cooled azeotrope into a phase separator, sending the m-xylene entrainer component containing the upper layer back to the rectification tower, sending the ethylene glycol phase containing a small amount of impurities in the lower layer into a reduced pressure distillation tower, separating light component impurities from the top of the tower under the operating pressure of 12KPa, and obtaining high-purity ethylene glycol from the bottom of the tower.
(2) Mixing high-purity ethylene glycol and adipic acid according to the ratio of 5: feeding the alkyd with the feeding ratio of 1 into a reaction kettle with nitrogen protection and stirring, esterifying at the reaction temperature of 200 ℃, removing water after reaction, adding a p-toluenesulfonic acid catalyst accounting for 0.5 percent of the total feeding amount to perform a first-stage polycondensation reaction, reacting at the temperature of 220 ℃ for 4 hours, then reducing the temperature to 65 ℃, vacuumizing when the acid value reaches 30mgKOH, performing a second-stage esterification reaction under the vacuum degree of 800mmHg, and finishing the reaction when the acid value is less than 10mgKOH to obtain the polyester polyol.
(3) FeSO is added to 5000 parts by mass of distilled water based on 100 parts by mass of a divalent metal salt 4 (100 parts by mass), fe 2 (SO 4 ) 3 (70 parts by mass), sodium dodecylbenzenesulfonate (30 parts by mass), 2- (2-hydroxy-5-methylphenyl) benzotriazole (40 parts by mass), and urea (200 parts by mass). And (2) carrying out hydrothermal reaction for 24h under the conditions of 110 ℃ and pH =10 by continuous stirring, filtering after the reaction is finished to obtain a product, washing the product by using a large amount of distilled water, and finally drying the product for 12h in vacuum to obtain the self-assembly modifier SDS-BTA-LDH.
(4) Adding SDS-BTA-LDH (5 parts by mass), a catalyst (triethylene diamine) 2.96 parts by mass, isocyanate (toluene diisocyanate (TDI)) 109 parts by mass, a chain extender (neopentyl glycol (NPG)) 9.6 parts by mass, a cross-linking agent (castor oil) 8.8 parts by mass and a foaming agent (dichloromethane) 0.99 parts by mass into a reaction container based on 100 parts by mass of polyester polyol, stirring and pre-reacting under the conditions of 50 ℃ and 0.5MPa, injecting the mixture into a mold with the preheating temperature of 80 ℃ for foaming, and drying the mold at the temperature of 150 ℃ for 2.5 hours to obtain the rigid polyurethane foam material.
Comparative example 1
(1) The ethylene glycol alcoholysis-methanol transesterification process for the waste polyester textiles comprises the steps of mixing a by-product containing ethylene glycol and adipic acid according to the weight ratio of 0.7:1, feeding the mixture into a reaction kettle provided with nitrogen protection and stirring, esterifying at the reaction temperature of 200 ℃, removing water after reaction, adding a p-toluenesulfonic acid catalyst accounting for 0.03 percent of the total feeding amount to perform a first-stage polycondensation reaction, reacting at the temperature of 220 ℃ for 4 hours, then reducing the temperature to 70 ℃, vacuumizing when the acid value reaches 15mgKOH, performing a second-stage esterification reaction under the vacuum degree of 670mmHg, and finishing the reaction when the acid value is less than 2mgKOH to obtain the polyester polyol.
(2) Adding ZnSO into 5000 parts by mass of distilled water based on 100 parts by mass of divalent metal salt 4 (100 parts by mass) and Fe 2 (SO 4 ) 3 (50 parts by mass) dodecyl benzene sulfonic acidSodium (27 parts by mass), 2- (2-hydroxy-5-methylphenyl) benzotriazole (30 parts by mass), and urea (150 parts by mass). And (2) carrying out hydrothermal reaction for 24h under the conditions of 95 ℃ and pH =9.5 by continuous stirring, filtering after the reaction is finished to obtain a product, washing the product by using a large amount of distilled water, and finally drying the product for 12h in vacuum to obtain the self-assembly modifier SDS-BTA-LDH.
(3) Adding 100 parts by mass of polyester polyol, SDS-BTA-LDH (5 parts by mass), a catalyst (triethylene diamine) 2.96 parts by mass, isocyanate (4,4-diphenyl isocyanate (MDI)) 109 parts by mass, a chain extender (1,3-propylene glycol (1,3-PDO)) 9.6 parts by mass, a crosslinking agent (trimethylolpropane (TMP)) 8.8 parts by mass and a foaming agent (cyclopentane) 0.99 part by mass into a reaction vessel, stirring at 25 ℃ and 0.1MPa for pre-reaction, injecting the mixture into a mold with the preheating temperature of 80 ℃ for foaming, and finally drying the mold at the temperature of 110 ℃ for 4 hours to obtain the rigid polyurethane foam material.
Comparative example 2
(1) The ethylene glycol containing by-product was reacted with toluene according to 27:1, under the conditions of 0.1MPa and 110.2 ℃, controlling the condensation reflux ratio to be 3, adopting an intermittent rectification mode to ensure that ethylene glycol and methylbenzene form an azeotrope to be distilled off from the top of the tower, cooling the azeotrope by a condenser, then sending the cooled azeotrope into a phase separator, sending the upper layer of the azeotrope containing methylbenzene back to the rectification tower, sending the lower layer of the ethylene glycol containing a small amount of impurities into a reduced pressure distillation tower, separating light component impurities from the top of the tower under the operating pressure of 9.8KPa, and obtaining high-purity ethylene glycol from the bottom of the tower.
(2) Mixing high-purity ethylene glycol and adipic acid according to the weight ratio of 0.7: feeding the alkyd of 1 into a reaction kettle with nitrogen protection and stirring, esterifying at the reaction temperature of 200 ℃, removing water after reaction, adding a p-toluenesulfonic acid catalyst accounting for 0.03 percent of the total feeding amount to perform a first-stage polycondensation reaction, reacting at the temperature of 220 ℃ for 4 hours, reducing the temperature to 70 ℃, vacuumizing when the acid value reaches 15mgKOH, performing a second-stage esterification reaction under the vacuum degree of 670mmHg, and finishing the reaction when the acid value is less than 2mgKOH to obtain the polyester polyol.
(3) Based on 100 parts by mass of polyester polyol, 2.96 parts by mass of a catalyst (triethylene diamine), 109 parts by mass of isocyanate (4,4-diphenyl isocyanate (MDI)), 9.6 parts by mass of a chain extender (1,3-propylene glycol (1,3-PDO)), 8.8 parts by mass of a crosslinking agent (trimethylolpropane (TMP)) and 0.99 part by mass of a foaming agent (cyclopentane) are added into a reaction vessel, stirred at 25 ℃ and 0.1MPa for pre-reaction, injected into a mold with the preheating temperature of 80 ℃ for foaming, and finally dried at the temperature of 110 ℃ for 4 hours to obtain the rigid polyurethane foam material.
Performance testing and analysis
(1) Thermal conductivity
According to the regulations GB/T10294-1988 or GB/T10295-1988, the aging of the product in the atmosphere should be more than 28d. The average temperature is 23 ℃ or 10 ℃, and the temperature difference of the cold plate and the hot plate is 23 +/-2 ℃.
(2) Dimensional stability
The procedure was as specified in GB/T21558-2008, with product sizes (100. + -.1). Times.100. + -.1). Times.25. + -. 0.5 mm, and 3 specimens per test condition. The test conditions are temperature (70 +/-2) DEG C and time of 48h.
(3) Compressive strength
According to the specification of GB/T8813-1988. The product size (100. + -.1) mm X (50. + -.1) mm, the number of specimens was 5. The test speed was 5mm/min. The direction of applied load should be parallel to the direction of product thickness (foam rise), measured as ultimate yield stress or compressive stress at 10% deformation.
(4) Limiting Oxygen Index (LOI)
Testing was carried out as specified in GB/8624-2012. That is, the sample maintains the minimum oxygen concentration for equilibrium combustion in the nitrogen-oxygen mixture under the predetermined conditions.
The examples were tested according to the evaluation criteria set forth above, and the test results are shown in fig. 1, 2, 3 and table 1.
Analyzing the results in FIG. 1, it can be found that SDS-BTA-LDH with hexagonal sheet morphology is successfully synthesized by the in situ assembly strategy.
The results of the analysis of the figure 2 show that the characteristic peak calculation at 2 theta =3.42 degrees in the X-ray diffraction diagram of the SDS-BTA-LDH shows that the modification of the SDS promotes the interlayer spacing of the LDH to 2.581nm, so that the polyurethane chain segment can smoothly enter the LDH layers, the dispersibility of the SDS-BTA-LDH in the polyurethane matrix is greatly improved, and the flame retardant and the uvioresistant performance of the material are effectively improved.
Analyzing the result of fig. 3, the ground ultraviolet light is mainly long-wave ultraviolet light (UVA) and medium-wave ultraviolet light (UVB), so the ultraviolet light absorption rate of the material in the wavelength range of 270-370nm is tested by the invention, and as can be seen from fig. 3, the ultraviolet light absorption rate of the rigid polyurethane foam material is obviously increased with the increase of the addition amount of the benzotriazole ultraviolet light absorbent, which indicates that the SDS-BTA-LDH modifier can obviously improve the ultraviolet resistance of the material.
As can be seen from Table 1:
analyzing the performance evaluation of the examples 1 to 10, it can be found that the yield and purity of the ethylene glycol are obviously improved along with the increase of the reflux ratio and the operation temperature in the azeotropic distillation tower.
By analyzing the evaluation of the properties of examples 1 to 10, it was found that the acid value of the polyester polyol showed a tendency to decrease and the hydroxyl value showed a tendency to increase as the molar ratio of the alkyd was increased. In addition, the increase of the temperature and the molar ratio of the alkyd can effectively improve the esterification rate of the reaction.
Analyzing the performance evaluation of the examples 1 to 10, it can be found that the halogen-free flame retardant and ultraviolet resistant rigid polyurethane foam material can be successfully prepared from the polyester polyol prepared by purifying the byproduct containing the hetero-ethylene glycol. Under various different synthesis schemes, the material can still maintain excellent heat resistance and mechanical properties. In addition, the limit oxygen index of the material can be effectively improved by increasing the addition amount of SDS-BTA-LDH, and the flame retardant property of the hard polyurethane foam material is greatly improved.
Analyzing the performance evaluation of comparative example 1, it can be found that the halogen-free flame-retardant and ultraviolet-resistant rigid polyurethane foam material prepared by directly using the by-product containing hetero-ethylene glycol as the raw material without rectification and purification treatment has poor heat insulation, mechanical properties and flame retardance.
Analyzing the performance evaluation of comparative example 2, it can be found that the rigid polyurethane foam material which is not flame-retardant modified with SDS-BTA-LDH has inferior flame retardancy compared to the material performance of 1-10.
TABLE 1
The above description is only exemplary of the invention and is not intended to limit the invention, which may be modified within the spirit and scope of the invention.
Claims (6)
1. A method for preparing rigid polyurethane foam by using byproducts of a chemical method regeneration process of waste textiles is characterized by comprising the following steps:
(1) Preparation of polyester polyol:
feeding the mixed solution of glycol and dibasic acid into a reaction kettle filled with nitrogen protection, carrying out esterification reaction under the condition of full stirring, removing water after the reaction is finished, adding a p-toluenesulfonic acid catalyst to carry out first-stage polycondensation reaction, reducing the system temperature, vacuumizing, and then carrying out second-stage polycondensation reaction to finally obtain polyester polyol;
the ethylene glycol is a purified product containing ethylene glycol byproducts obtained in the chemical regeneration process of the waste textiles;
the method for purifying the ethylene glycol comprises the following steps: feeding the ethylene glycol-containing by-product and an entrainer into an azeotropic distillation tower, refining ethylene glycol by adopting an intermittent distillation mode, distilling an azeotrope formed by the ethylene glycol and the entrainer from the top of the tower after the distillation is finished, cooling the azeotrope by a condenser, feeding the cooled azeotrope into a phase separator, feeding the entrainer-containing phase on the upper layer back to the distillation tower, feeding the ethylene glycol phase containing a small amount of impurities on the lower layer into a reduced pressure distillation tower for impurity separation, and finally, obtaining the distillate at the top of the distillation tower, namely the high-purity ethylene glycol;
the entrainer is any one of methylbenzene, n-butyl ether and m-xylene; the mass charge ratio of the ethylene glycol-containing by-product to the entrainer is 10-30:1, the operating temperature of the azeotropic distillation tower is 110-130 ℃, the operating pressure is 0.1-0.3MPa, and the reflux ratio is 1-15; the operating pressure of the reduced pressure distillation tower is 5-12KPa;
(2) Preparation of self-assembled modifier SDS-BTA-LDH:
slowly adding a quantitative soluble divalent and trivalent metal salt solution into a mixed solution of sodium dodecyl sulfate and a benzotriazole ultraviolet absorbent, adding a proper amount of alkaline substances into the mixed solution, carrying out hydrothermal reaction under the condition of continuous stirring, filtering to obtain a product after the reaction is finished, washing with a large amount of distilled water, and finally drying in vacuum to obtain self-assembled modified SDS-BTA-LDH;
(3) Preparing a flame-retardant and ultraviolet-resistant rigid polyurethane foam material:
adding the metered polyester polyol, isocyanate, SDS-BTA-LDH, a chain extender, a cross-linking agent, a foaming agent and a catalyst into a container together, uniformly stirring for reaction, then injecting the mixture into a mold for foaming, and finally drying the foamed material in the mold to obtain the rigid polyurethane foam.
2. The method for preparing the rigid polyurethane foam by using the byproducts of the chemical recycling process of the waste textiles as claimed in claim 1, wherein the dibasic acid in the step (1) is any one of adipic acid, terephthalic acid and isophthalic acid; the mass charge ratio of the ethylene glycol to the dibasic acid in the esterification reaction is 0.5-5:1, the esterification reaction temperature is 110-200 ℃; the addition amount of the p-toluenesulfonic acid catalyst in the first-stage polycondensation reaction accounts for 0.03-0.5% of the total feed ratio, the reaction temperature is 200-300 ℃, the reaction time is 2-5h, the system temperature is reduced to 50-80 ℃ after the first-stage polycondensation reaction is finished, the second-stage polycondensation reaction is carried out after the system acid value is reduced to 10-30mgKOH and the system is vacuumized to 500-800mmHg, and the reaction is finished when the system acid value is 1-10mgKOH, so that the polyester polyol can be obtained.
3. The method for preparing rigid polyurethane foam by using the byproduct of the chemical recycling process of waste textiles in claim 1, wherein the divalent cation in the soluble divalent and trivalent metal salt solution in the step (2) is divalent cationCu 2+ 、Zn 2+ 、Ni 2+ 、Mg 2+ Wherein the trivalent cation is Fe 3+ 、Al 3+ Any one of the above; the anion in the soluble divalent metal salt and the soluble trivalent metal salt is NO 3 - 、SO 4 2- Any one of the above; the benzotriazole ultraviolet absorbent is any one of 2- (2-hydroxy-5-methylphenyl) benzotriazole, 2- (2-hydroxy-3-tert-butyl-5-methylphenyl) -5-chlorobenzotriazole and 2- (2-hydroxy-3,5-di-tert-phenyl) -5-chlorobenzotriazole, and the alkaline substance is any one of urea, ammonia water or sodium hydroxide.
4. The method for preparing rigid polyurethane foam by using byproducts of the chemical regeneration process of waste textiles as claimed in claim 1, wherein the preparation of the self-assembled modified SDS-BTA-LDH in the step (2) is carried out by taking 100 parts by mass of divalent metal salt as a reference, and the feeding amounts of the rest raw materials are as follows: 20-70 parts of trivalent metal salt, 10-30 parts of sodium dodecyl benzene sulfonate, 20-40 parts of benzotriazole ultraviolet absorbent and 50-200 parts of alkaline substance; the temperature of the hydrothermal reaction is 60-110 ℃, the time is 10-24h, and the pH value of the reaction system is 7-10.
5. The method for preparing the rigid polyurethane foam by using the byproducts of the chemical regeneration process of the waste textiles as claimed in claim 1, wherein the rigid polyurethane foam preparation process in step (3) is based on 100 parts by mass of polyester polyol, and the feeding amounts of the other raw materials are as follows: 0.5-5 parts of SDS-BTA-LDH, 0.1-3 parts of catalyst, 90-120 parts of isocyanate, 1-10 parts of cross-linking agent, 0.1-1 part of foaming agent and 1-10 parts of chain extender, wherein the reaction temperature for preparing the hard polyurethane foam material is 20-50 ℃, the pressure is 0.1-0.5MPa, the preheating temperature of a die is 50-80 ℃, the drying temperature of the foam material is 90-150 ℃, and the drying time is 2-5h.
6. The method for preparing rigid polyurethane foam by using byproducts of a chemical recycling process of waste textiles as claimed in claim 1, wherein the isocyanate in the step (3) is any one of 4,4-diphenyl isocyanate, polymethylene polyphenyl polyisocyanate and toluene diisocyanate; the chain extender is any one of 1,3-propylene glycol, 1,6-hexanediol and neopentyl glycol; the cross-linking agent is any one of trimethylolpropane, castor oil and pentaerythritol; the foaming agent comprises any one of cyclopentane, n-pentane and dichloromethane; the catalyst is any one of triethylene diamine, dimethyl cyclohexylamine, stannous octoate and dibutyltin dilaurate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210041468.XA CN114276516B (en) | 2022-01-14 | 2022-01-14 | Method for preparing hard polyurethane foam by using byproducts of waste textile chemical method regeneration process |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210041468.XA CN114276516B (en) | 2022-01-14 | 2022-01-14 | Method for preparing hard polyurethane foam by using byproducts of waste textile chemical method regeneration process |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114276516A CN114276516A (en) | 2022-04-05 |
| CN114276516B true CN114276516B (en) | 2022-11-18 |
Family
ID=80880957
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210041468.XA Active CN114276516B (en) | 2022-01-14 | 2022-01-14 | Method for preparing hard polyurethane foam by using byproducts of waste textile chemical method regeneration process |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114276516B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117486720A (en) * | 2023-11-06 | 2024-02-02 | 浙江佳人新材料有限公司 | DMT remelting recovery process in chemical recycling process of waste textiles |
Family Cites Families (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| IT1277997B1 (en) * | 1995-05-10 | 1997-11-12 | Coim Spa | POLYESTERS POLYOLS, ESPECIALLY FOR THE PRODUCTION OF RIGID POLYURETHANE FOAMS. |
| TWI290933B (en) * | 2000-07-31 | 2007-12-11 | Mitsui Takeda Chemicals Inc | Method and apparatus for producing polyester polyol, polyester polyol and polyurethane foam |
| CN1333005C (en) * | 2005-12-19 | 2007-08-22 | 北京化工大学 | Supermolecular interlayer structured ultraviolet light absorbent, its preparation method and uses |
| CN101265323A (en) * | 2007-03-16 | 2008-09-17 | 张鹏飞 | Polyester polyol |
| JP5397170B2 (en) * | 2009-11-09 | 2014-01-22 | 川崎化成工業株式会社 | Rigid polyurethane foam composition and method for producing rigid polyurethane foam |
| CN101974220B (en) * | 2010-10-08 | 2012-01-04 | 长春工业大学 | Polyurethane foaming thermal insulation material prepared by utilizing by-product resin C of chemical alcohol and preparation method |
| PT106256A (en) * | 2012-04-17 | 2013-10-17 | Chemetall Gmbh | METHOD SURFACES COATING PROCESS WITH COATINGS CONTAINING LAMELAR DUAL HYDROXIDE PARTICLES. |
| AU2013257710B2 (en) * | 2012-05-08 | 2016-10-20 | Cellixbio Private Limited | Compositions and methods for the treatment of neurological disorders |
| CN103664516B (en) * | 2013-11-29 | 2015-08-05 | 中国五环工程有限公司 | The ethylene glycol separating technology of synthetic gas preparing ethylene glycol |
| CN104693397A (en) * | 2013-12-09 | 2015-06-10 | 南京美鼎科技有限公司 | Method for recycling waste polyurethane product |
| CN104004179A (en) * | 2014-04-19 | 2014-08-27 | 上海东大化学有限公司 | Method for preparation of polyether polyol and hard foam polyurethane from waste recovered material and products thereof |
| CN104289184A (en) * | 2014-10-23 | 2015-01-21 | 北京化工大学 | 2, 4, 6-trichlorophenol adsorbing agent and application thereof |
| CN105219066B (en) * | 2015-10-09 | 2018-02-23 | 北京化工大学 | A kind of polyurethane/nano hydrotalcite composite material with high-damping, UV absorption and toughness reinforcing performance and preparation method thereof |
| CN113185662B (en) * | 2021-04-29 | 2022-07-26 | 郑州大学 | Low-temperature-resistant ultraviolet-aging-resistant thermoplastic polyurethane elastomer and preparation method thereof |
-
2022
- 2022-01-14 CN CN202210041468.XA patent/CN114276516B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN114276516A (en) | 2022-04-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Heiran et al. | Glycolysis: An efficient route for recycling of end of life polyurethane foams | |
| CN1176965C (en) | Fine-cell water-driven rigid expanded polyurethanes foam | |
| CN114276516B (en) | Method for preparing hard polyurethane foam by using byproducts of waste textile chemical method regeneration process | |
| EP1799736A2 (en) | Method for producing rigid polyurethane foams | |
| AU2006218395A1 (en) | Novel polyols derived from a vegetable oil using an oxidation process | |
| EP4010414A1 (en) | Improved method of recycling polyurethane materials | |
| EP1893905A1 (en) | Method for the production of vacuum insulation panels | |
| US20240052126A1 (en) | Systems and Methods for Image-Based Location Determination | |
| WO2019219814A1 (en) | Improved method of recycling polyurethane materials | |
| WO2008058863A1 (en) | Method for the production of rigid polyurethane foams | |
| JP2013521354A (en) | Polyurethane production | |
| CN114127149B (en) | Low TVOC flame retardant polyurethane spray foam system | |
| RU2222550C2 (en) | Jointly initiated polyether-polyol and a method for preparation thereof | |
| CN103249752B (en) | Method for producing flexible polyurethane foams | |
| CN113402875A (en) | Graphene oxide/fly ash modified regenerated polyurethane composite material and preparation method thereof | |
| CN101029119A (en) | Production of recovered grease polybasic alcohol and its hard polyurethane foaming plate | |
| WO2014029646A1 (en) | Plastically deformable polyurethane polyamide rigid foam | |
| DE102007052599A1 (en) | Procedure for production of polyether alcohols used in manufacturing of hard foams, involves converting starting material liquid H-functional compounds with alkyl oxides at ambient temperature in presence of tertiary amines as catalysts | |
| CN105175701B (en) | A kind of preparation method and application of PET Quito member synergistic polyalcohol | |
| EP1512707A2 (en) | Open celled rigid polyurethane foams | |
| CN111372963B (en) | Method for producing open-celled rigid foams containing urethane and isocyanurate groups | |
| KR101447247B1 (en) | Preparation method of recycled polyol using specific catalyst, production method of polyurethane foam using the recycled polyol | |
| Manjunathan et al. | Integrated process towards sustainable renewable plastics: Production of 2, 5-furandicarboxylic acid from fructose in a base-free environment | |
| KR20220021779A (en) | Method for Depolymerization of Polyethylene terephthalate Using Zeolite Based Catalyst | |
| KR101476223B1 (en) | Recovering method highly efficiently from waste polyurethane using recycled polyol |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |