Classifications

• • E—FIXED CONSTRUCTIONS
  • E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
  • E01C—CONSTRUCTION OF, OR SURFACES FOR, ROADS, SPORTS GROUNDS, OR THE LIKE; MACHINES OR AUXILIARY TOOLS FOR CONSTRUCTION OR REPAIR
  • E01C7/00—Coherent pavings made in situ
  • E01C7/08—Coherent pavings made in situ made of road-metal and binders
  • E01C7/18—Coherent pavings made in situ made of road-metal and binders of road-metal and bituminous binders
  • E01C7/26—Coherent pavings made in situ made of road-metal and binders of road-metal and bituminous binders mixed with other materials, e.g. cement, rubber, leather, fibre
  • E01C7/267—Coherent pavings made in situ made of road-metal and binders of road-metal and bituminous binders mixed with other materials, e.g. cement, rubber, leather, fibre with sulfur
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L95/00—Compositions of bituminous materials, e.g. asphalt, tar, pitch
• • E—FIXED CONSTRUCTIONS
  • E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
  • E01C—CONSTRUCTION OF, OR SURFACES FOR, ROADS, SPORTS GROUNDS, OR THE LIKE; MACHINES OR AUXILIARY TOOLS FOR CONSTRUCTION OR REPAIR
  • E01C7/00—Coherent pavings made in situ
  • E01C7/08—Coherent pavings made in situ made of road-metal and binders
  • E01C7/18—Coherent pavings made in situ made of road-metal and binders of road-metal and bituminous binders
  • E01C7/26—Coherent pavings made in situ made of road-metal and binders of road-metal and bituminous binders mixed with other materials, e.g. cement, rubber, leather, fibre
  • E01C7/265—Coherent pavings made in situ made of road-metal and binders of road-metal and bituminous binders mixed with other materials, e.g. cement, rubber, leather, fibre with rubber or synthetic resin, e.g. with rubber aggregate, with synthetic resin binder

Definitions

• bitumens have been modified by the addition of polymers in order to improve their rheological properties and, moreover, to slow down their ability to age.
• Two main effects are sought. First increase the plasticity range, so that in high temperature conditions, the bitumen retains a sufficient viscosity so that it prevents asphalt mixes and sheets of waterproofing complexes from deforming. Secondly, in particular at low temperatures, reduce its rigidity by transferring large elastic deformation capacities to it in order to allow it to withstand high stresses.
• polymers are commonly used to make this type of modification to bitumen. Mention may be made of: polyolefins, polyvinyl acetates or chlorides, elastomers, etc.
• bitumens these are the elastomers which best contribute to give elasticity and possibly plasticity.
• the introduction of these polymers into bitumens is not easy. It is the morphological composition of the base bitumen; that is to say its groups of chemical components: saturated, aromatic, polar and asphaltenes, which condition the choice of the polymer (s) and limit the solubility (ies).
• the level of modification that we can hope to achieve is almost predefined in advance.
• STYRENE-BUTADIENE STYRENE-BUTADIENE
• SB STYRENE-BUTADIENE
• SBS STYRENE- BUTADIENE-STYRENE
• SI STYRENE-ISOPRENE
• SIS STYRENE-ISOPRENE-STYRENE
• EPDM ETHYLENE-PROPYLENE-DIENE
• This product is not strictly speaking a real polymer. It is its low molecular weight and the judicious choice of the styrene / butadiene distribution which makes it compatible with all bitumens. Depending on the penetration of the bitumen it is up to contents which can exceed thirty percent which can be dissolved. In return, this one, without the use of the chemical reaction with sulfur, modifies very little the natural properties of the starting bitumen. Nevertheless, for order-makers of six percent in SB polymer, these crosslinked products tend to evolve as soon as the crosslinking produced and to polymerize, in their entirety during manufacture or during their storage (formation of a gelatinous mass).
• the principle was: in a heated and stirred reactor, are introduced with stirring, in the quantities required by the formulation, successively, the necessary bitumen, then for a relatively long time, depending on the quantity to be used, the polymer, with possibly l '' using a liquid / solid grinder helping to accelerate the dissolution of the solid and if necessary additives.
• the mixture reaches an aspect of satisfactory homogeneity, it is then proceeded to the incorporation of sulfur or any other molecule capable, by thermal decomposition of producing it, taking great care that the solid, at the time of its contact with the surface of the medium, be immediately entrained within the mixture.
• a binder containing between three and four percent of polymer six to seven hours are necessary to manufacture such a product with a phase of at least two hours between the start of introduction of the sulfur, the end of agitation and the transfer of the binding to storage.
• an SB polymer bitumen concentrate physical type of mixture, from the range of penetration bitumens between 60/70 (0.01 mm) and 600/800 (0.01 mm), and of polymers of styrene-butadiene, styrene-butadiene-styrene, styrene-isoprene, styrene-isoprene-styrene type polymers.
• 200/500 penetration bitumens will be used in which 10 to 30 percent of polymer, preferably of the styrene-butadiene type, whose molecular weight will be between 55,000 and 95,000 grams, may be added. After dissolution, this product will represent the basic concentrate of polymer bitumen.
• a second bitumen constituent containing the chemical reagent preferably sulfur or a sulfur donor, to be chosen from molecules of the polysulfide type, etc.
• the bitumen will be chosen from bitumen with a penetration between 10/20 and 180/200.
• the amount of sulfur or equivalent sulfur released by the donor agent will be between 1 and 15 percent.
• a third base may be produced containing other polymers of noble quality or from recovery, of the polyethylene or polypropylene or acetate or vinyl chloride or polyurethane type, or recovery rubber from tires.
• the bitumen will preferably be chosen from soft bitumen with high penetration.
• the polymer concentration will depend on the type (s) of polymers used. Depending on compatibility, it may be between 5 and 15 per cent relative to the bitumen and may also be introduced, chemical additives surfactant (polyamines, fatty organic acids)
• the installation will include the following equipment: injection pumps, mass flow meters, regulated and slaved valves, temperature indicators, check valves.
• the whole is connected by piping traced with hot oil and connected to the various tanks. All these pipes lead to the inlet / supply of an in-line mixer which can be in various forms: static mixer or chamber with dynamic agitators.
• the static mixer will preferably be chosen, of simple design and will be sized for the hourly production range sought and for the different viscosity values of the products it will have to mix. Of course the definition of the characteristics of the mixer will condition the characteristics of the metering pumps and in particular their discharge pressure.
• all the tanks and all the equipment will be kept at high temperatures and adapted to the type of product stored, i.e. between 140 ° and 250 ° C. At the required proportion, the different pumps will send each basic mixture to the mixer:
• the online mixer designed to disperse intimately, continuously, inside, all of the components between them, will help to initiate the reaction between the constituents of the bitumen, the sulfur and the polymer SB, then to promote its development leading on obtaining the finished crosslinked concentrated polymer bitumen at the outlet.
• the binder is sent directly to the application unit, preferably by connecting the outlet pipe by means of a shortest length possible either to: a coating plant mixer or injection ramp of a drum-dryer-mixer-wrapper type (TSM / E) of a fixed or mobile coating plant or of a drum of a coating plant of a mobile hot recycling unit of asphalt or at the feed head of a colloidal mill for emulsion production or at the feed of a coating machine for the production of sheets or waterproofing complexes.
• TSM / E drum-dryer-mixer-wrapper type
• the process for manufacturing a cross-linked bitumen with 12 percent SB polymer and 0.3 percent sulfur is shown.
• Two mixtures are prepared, the first (A) perfectly homogeneous and hot at 180 ° C will consist of 85 parts of a direct distillation bitumen of penetration 350 (0.01 mm) with 15 parts of a biblock styrene-butadiene polymer proportion 25/75; the second mixture (B) maintained at 160 ° C. is composed of 98.5 parts of the same bitumen of penetration 350 with 1.5 parts of dissolved sulfur.
• Two pumps, with sufficient discharge pressure to overcome the pressure losses of the entire circuit, will inject the two fluids separately on the supply head of the static mixer.
• each pump will be regulated by mass meters acting on slave solenoid valves. Likewise, the temperatures of the mixtures will be identified and regulated.
• the two mixtures are then injected in the proportion of 80 parts of (A) and 20 parts of (B).
• the product obtained from the mixer immediately exhibits all of its properties for use in a new application as cross-linked bitumen with 12 percent polymer.
• This invention has extremely interesting advantages. It will allow the use of crosslinked binders with polymer contents greater than 10 or even up to 35 percent for the manufacture of special asphalt for the road. Binders from the batch process did not allow such materials to be obtained. In this, this invention opens the way to obtaining mixes with very high properties, which will lead to mixes intended for new uses guaranteeing a longer life for pavement structures: reinforcing mixes and flexible mixes very highly draining (with a high degree of voids> 30 percent) coated with ultra-thin etc.
• binders with a very high polymer concentration, can be produced as an agent for regenerating old bitumens contained in old asphalt mixes and using the propagation capacity of the crosslinking reaction provided by a sulfur crosslinked polymer bitumen to any other new or aged natural bitumen as claimed in Spanish patent application P 9601837.
• the recovery of old coated materials by the hot recycling technique consists in reproducing a new bitumen by reusing all of the old materials.
• the initial quantity of bitumen contained in a material to be regenerated is generally of the order of 5 percent or even more, which leaves a small possibility of quantity of addition of regenerating agent (1.5 or even ⁇ 1 percent ).
• the formulation of such a regenerating agent should contain a quantity of vulcanized polymer so high that no process would allow its production today. It can therefore be seen, the advantage of the invention which allows the production of a bitumen concentrated in crosslinked polymer, just at the time, or this binder "regenerating agent" is introduced into the mixer or in TSM / E. This technique implies that the materials are previously divided, so that they can be advantageously reheated.
• the waterproofing industry also represents another example of application of the invention.
• For the manufacture of complex sheets and waterproofing screeds it uses binders modified by high concentrations of polymers. Because of the problems previously exposed, the mixtures produced cannot exceed 10 percent and these products after their manufacture cannot be stored. The use of the continuous production process would allow continuous and custom feeding of coating machines, eliminating known problems, while benefiting from the new performance provided by these new binders. DESCRIPTION OF THE INVENTION
• a first series of tests is carried out, consisting of making six mixes with increasing polymer content (3,6,9, 12, 15 and 20 percent) and this with each type of polymer. This operation will be carried out in glass flasks fitted with agitators, condensers and heated by temperature-controlled flask heaters. Temperatures and duration of agitation will be adapted according to each formulation, the type of bitumen, the nature and the quantity of polymer. The higher the hardness of the bitumen and the quantity of polymer, the greater the duration of agitation and the temperature. For these tests the temperature will be between 160 ° and 195 ° C and the stirring time will vary between '3 and 12 hours. The homogeneity of the dispersion will be checked by visual observation of a glass rod immersed in the medium. A final control will be done by sieving on a fine sieve (80 microns), (see table n ° 2)
• bitumen (A) and (B) dissolves in bitumen (A) and (B) at least up to a concentration of 20 percent and also in bitumen (C) up to a concentration of at least 15 percent
• Polymer (d) is soluble at least up to 9 percent in bitumens (A) and (B) as well as polymer (c) in bitumen (B). At a content of 6 percent the polymer (a) is insoluble in bitumen (B) and at this same concentration polymers (a) and (c) are insoluble in bitumen (C). Generally, at a concentration of 3 percent, the four polymers are soluble in the three bitumens.
• bituminous binder per cent of aggregates.
• the bitumen used will be of the modified type, obtained according to the process of the invention and leaving at 180 ° C from the static mixer to be poured into hot aggregates brought to 180 ° C.
• the binder will be introduced, in the desired quantity, into the kneaded and heated aggregates.
• MARSHALL test pieces will be manufactured according to the standard: compacting by 75 strokes on each side. After regulatory conservation (dry and wet), the CANTABRO test, consisting in monitoring the loss of mix by impact and attrition of MARSHALL test pieces placed in a LOS ANGELES cylinder, will be carried out according to protocol conditions. For a type of asphalt draining to such a degree of vacuum, the material losses are remarkably reduced:
• Example 3A Under the same conditions as in Example 3A, the same type of asphalt will be manufactured, but using a crosslinked binder obtained according to the traditional method, of batch discontinuous type, containing 12 percent of polymer SB (b ). It is bitumen RCb (pd) which has been previously maintained for 24 hours in a closed container, placed in an oven at 170 ° C. Two hours before the manufacture of the mix, the temperature of the oven will be increased at 180 ° C. It will be noted that during the manufacture of the draining asphalt, the bitumen RCb (pd) due to its very high viscosity does not allow the correct coating of the gravel. Another test of the manufacture of the mix will then be repeated, bringing the temperature of the two components to 210 ° C. beforehand. This will not improve the quality of the coating. Nevertheless, on this latter coated MARSHALL test tubes will be produced under the same conditions as above. The results found are as follows:
• the results of the 3A mix are of a level higher than the best 0/10 type drainers based on traditional polymer bitumen, while the mix obtained with the binder from the normal process, despite having a level of characteristics. equivalent modification, could not be used without subsequent risk of disorders.
• the bitumen RCb (pc) produced according to the invention will be produced at a temperature of 185 ° C just at the time of the manufacture of the mix, in order to be injected on the materials heated 180 ° C
• the asphalt obtained will have a homogeneous and normal appearance. It will be compacted in the form of plates until a well-densified material is obtained.
• the other bitumen, RCb (pd) will be previously kept for 24 hours in an oven at 170 ° C, then brought to 180 ° C two hours before manufacturing the mix; the aggregates being them maintained at 180 ° C. Under these conditions and with this formulation, it will not be possible to coat the large elements.
• the binder will be made from the same material as that used in Example 3A.
• the modified bitumen obtained according to the process will be of the RAb (pc) type, using the base bitumen (A) with a final polymer content (b) of 12 parts as well as with 0.15 parts of sulfur for 87.85 parts of bitumen.
• the static mixer output will be connected to the input a colloid mill for the production of bituminous emulsions.
• We will choose a production rate of polymer bitumen crosslinked continuously through the static mixer, compatible with that of the emulsifier.
• the temperature used for the manufacture of the modified binder will be between 160 ° and 165 ° C and an aqueous phase of the following composition will be prepared:
• the introduction of the binder exiting from the static mixer is done gradually, so as to bring its speed to a ratio of 65% relative to the total emulsion.
• an emulsion of normal appearance is obtained which is at a temperature of 92 ° C.
• the analysis will indicate a pH of 2.8 and a water content of 34.6%.
• Emulsion will be deposited on metal cups. These will be placed for 15 days in a ventilated oven and maintained at 50 ° C. The binder thus recovered will be used to prepare tensile test pieces which will be tested by giving the results below:
• Binder Rab (pc) recovered by Elongation at break Stress on evaporation after passing 900% rupture 4.2 kg / cm2 emulsion
• the regenerated mix type 0/14, must have the following characteristics:
• Table 5 indicates the composition of the old asphalt to recycle, its bitumen content is 4.52 ppc.
• bitumen (A) of penetration 347 (0.01 mm) of Example No. 1 From the bitumen (A) of penetration 347 (0.01 mm) of Example No. 1 and by the addition of 11% of a bitumen of penetration 90 (0.01 mm) of the same origin as bitumen (A), we will obtain by mixing a new penetration bitumen 300 called “regenerating agent” (AR).
• AR regenerating agent
• bitumen (AR) a bitumen concentrated in polymer (b) is prepared with 10 parts of polymer (b) for 90 parts of bitumen (AR). After dissolution, 0.15 parts of sulfur are slowly added to this mixture. After two hours of stirring, a conventional crosslinked polymer bitumen is obtained called “conventional crosslinked regenerating agent” (ARRC). From the bitumen (AR) penetrating 300 (0.01 mm), we will prepare a polymer concentrate (b) by dissolving 12.5 parts of polymer (b) for 87.5 parts of bitumen (AR). On the other hand, we will achieve with this same bitumen (AR), a mixture with 0.75 part of sulfur in 99.25 parts of bitumen (AR).
• ARRC conventional crosslinked regenerating agent
• a regenerating bitumen will be produced continuously, according to the method of the invention, by mixing by injection into the static mixer, 80 parts of the polymer concentrate with 20 parts. bitumen sulfur. At the end of it, we will obtain a crosslinked polymer bitumen called “crosslinked regenerating agent, continuous process” (ARRPC).
• ARRPC crosslinked regenerating agent, continuous process
• the old bitumen will be extracted by dissolution and then evaporation of the solvent, and from the three types of binder above indicated, the regenerated bitumen as produced in the context of will be reconstituted by simylation. a hot recycling operation.
• Each binder will be regenerated by mixing 76 parts of bitumen extracted from the mills with 24 parts successively of each of the three bitumens considered as a regeneration additive.
• Each of the three new binders thus obtained will be analyzed: Regenerated bitumen; Conventional crosslinked regenerated polymer bitumen (BRRC) and Continuously regenerated crosslinked polymer bitumen (BRRPC); see values gathered in table n ° 6. table n ° 6
• ARRC regenerating agent
• a regeneration agent having a very high polymer concentration will be produced according to the continuous production process of the invention, taking into account that the millet to be recycled is a mix of type 0/14 which contains 5, 2% bitumen. Knowing that the performance of recycled asphalt requires a contribution of 2.5% in the regenerated bitumen, the formulation of the two components to be produced previously used for the continuous production of the regenerating agent will be as follows: polymer bitumen with 23.4 parts of polymer (b) in 76.6 parts of bitumen (A) and bitumen sulfur with 3.75 parts of sulfur in 96.25 parts of bitumen (A).
• this regenerating agent will be done through the installation described previously, the metering pumps will inject the two components into the static mixer in line according to the proportions of 80 parts of polymer bitumen for 20 parts of the mixture of sulfur bitumen, with a mixer outlet temperature of 180 ° C.
• this regenerating agent will be used to manufacture a recycled asphalt, followed by the preparation of the set of test pieces for evaluation and the evaluation results are shown in table 10 below.
• Example 5A Referring to the conditions of Example 5A, that is to say with the use of the regenerating agent (ARRPC), 10 parts of low density polyethylene polymer will be added to the reactive bitumen mixture in 90 parts of the bitumen mixture. reagent. With this new product and by repeating the same conditions as those of Example 5A, according to the process of the invention, we will manufacture:
• the good characteristics noted confirm the good integration of the polyethylene in the crosslinked network, contributing to bringing more rigidity to the bituminous medium.
• This criterion is assessed by comparing the values of the recycled bitumen BR and the regenerated bitumen BRRPC of Example 5A and confirm the possibilities of reuse of the used polymers through the invention.
• a polymer bitumen crosslinked with 28% styrene-butadiene polymer will be made by mixing 31, 1 parts of polymer (b) in 68.9 parts of bitumen (A): compound (J) and on the other hand, reactive mixture by introducing 1, 3 parts of sulfur into 98.7 parts of bitumen (A): compound (K). From the above equipment and respecting the same protocol as that of Example No. 3A, 90 parts of the polymer bitumen (J) will be mixed in 10 parts of reactive sulfur bitumen (K).
• Table No. 12 The evaluation of the characteristics of the binder resulting from the continuous production are summarized in table No. 12 below.
• Priority data KG, KZ, MD, RU, TJ, TM), European patent (AT, BE, CH,
• the invention concerns the continuous production of bituminous materials modified by addition of polymers and reacted with sulfur.
• the binders resulting from said method can contain very high amounts of polymers also combined with secondary materials such as: rubber, various plastics and waste lubricants.
• This type of binders which cannot be obtained by discontinuous batch technology, results from the continuous mixing of several bituminous constituents through a static mixer.
• Said binders provide very high performance bituminous materials and agents for regenerating old bituminous materials contained in waste road materials, in the process of hot recycling of coated materials. They are also used for producing novel emulsions of highly modified binders, with multiple applications and in particular for cold recycling.
• This novel method by regeneration of old bitumen contained in waste coated materials, represents a means for waste conversion and for limiting the use of bitumen and road surfacing aggregates.
• bitumens modified by adding polymers and reacted with sulfur It is a continuous manufacturing process for bitumens modified by adding polymers and reacted with sulfur.
• the binders resulting from this process can contain very large quantities of polymers also associated with recovery materials such as: rubber, various plastics and used lubricants.
• the continuous mixing of several bituminous constituents, through a static mixer, leads to this type of binder, which cannot be obtained with batch batch technology. They make it possible to obtain bituminous materials with a very high level of performance and regenerating agents for old bitumens contained in worn pavement materials, within the framework of hot recycling of asphalt. They also contribute to obtaining new emulsions of highly modified binders, for multiple applications and in particular for cold recycling.
• This new process by regenerating the old bitumens contained in used asphalt, represents a means of recovery and limitation of the use of bitumen and road aggregates.
• the polymer (s) introduced into the bitumen are of the elastomer type synthetic, preferably chosen from: styrene-butadiene statistics or styrene-butadiene (SB) sequenced or styrene-isoprene bisequenced or styrene-butadiene-styrene triblock (SBS) or styrene-isoprene-styrene triblock (SIS) or ethylene-propylene-diene copolymer type (EPDM).
• SB styrene-butadiene statistics or styrene-butadiene (SB) sequenced or styrene-isoprene bisequenced or styrene-butadiene-styrene triblock (SBS) or styrene-isoprene-styrene triblock (SIS) or ethylene-propylene-diene copo
• ELASTOMERICS AND THERMOSPLATICS according to claims 1 ° to 4 ° in which the second constituent to be injected is a bituminous mixture, composed of sulfur or any another sulfur compound capable of releasing free sulfur by thermal decomposition.
• PROCESS FOR THE CONTINUOUS MANUFACTURE OF BITUMS MODIFIED BY HIGH POLYMER CONCENTRATIONS AND BY SULFUR REACTION, PERFORMING THE RECYCLING OF USED PLASTICS AND RUBBER AND HAVING ELASTOMERIC AND THERMOSPLATIC PROPERTIES according to claims 1 ° to 15 ° its use allows the manufacture for immediate use, of elastomeric bitumens reacted with sulfur with very high polymer concentrations, these products being impossible to obtain by the batch production process.
• PROCESS FOR THE CONTINUOUS MANUFACTURE OF BITUMS MODIFIED BY HIGH POLYMER CONCENTRATIONS AND BY SULFUR REACTION, PERFORMING THE RECYCLING OF USED PLASTICS AND RUBBER AND HAVING ELASTOMERIC AND THERMOSPLATIC PROPERTIES according to claims 1 to 17 the immediate union of the output of the manufacturing device as resulting from the invention, or of the mixer, at the feed head of a colloid mill for manufacturing emulsions, makes it possible to obtain emulsions in which the dispersed bitumen has a crosslinked polymer concentration of between 0.5 to 35 parts of polymer per 99.5 to 65 parts of bitumen.

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• Engineering & Computer Science (AREA)
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• Chemical & Material Sciences (AREA)
• Architecture (AREA)
• Health & Medical Sciences (AREA)
• Materials Engineering (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• Compositions Of Macromolecular Compounds (AREA)
• Road Paving Structures (AREA)
• Processes Of Treating Macromolecular Substances (AREA)

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• 1998
  • 1998-05-14 US US09/424,662 patent/US6380284B1/en not_active Expired - Lifetime
  • 1998-05-14 CA CA002290678A patent/CA2290678A1/fr not_active Abandoned
  • 1998-05-14 WO PCT/FR1998/000956 patent/WO1998054263A1/fr active Application Filing
  • 1998-05-14 BR BR9809513-7A patent/BR9809513A/pt not_active IP Right Cessation
  • 1998-05-14 EP EP98925705A patent/EP0994922A1/de not_active Withdrawn
  • 1998-05-14 AU AU77724/98A patent/AU7772498A/en not_active Abandoned
  • 1998-05-29 AR ARP980102510A patent/AR008197A1/es unknown

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