Abstract: A process is developed for recycling a polyolefin cross-linked substance having a cross-linkage, a polyolefin foamed substance free from a cross-linkage or a polyolefin foamed substance having a cross-linkage. The process includes the step of heating the polyolefin cross-linked substance together with a cross-linkage breaking agent, whereby breaking the cross-linkage to recycle the polyolefin cross-linked substance into a moldable thermoplastic resin. Further, the process includes the step of adding a foaming-agent-decomposition facilitating agent to the polyolefin foamed substance in the course of thermally melting the polyolefin foamed substance, whereby decomposing a residual foaming agent remaining in the polyolefin foamed substance.

Abstract: Tires are converted to rubber particles and inorganic compounds are removed from the tires by treating the tires in a closed reactor with a nitric acid solution having a nitric acid concentration above 60%. In the preferred embodiment, any steel belts contained in the tires are first removed. The tires are then treated with a solution of concentrated nitric acid in which the acid concentration is maintained above 60% which extracts inorganic compounds such as zinc, sulfur and calcium from the tires and converts the tires into rubber particles.

Abstract: Polycarbonates are recycled without the need for chemical modification by dissolution in a solvent followed by removal of any insoluble materials and precipitation by addition of a non-solvent. The precipitation step may be followed by solid state polymerization of the recycled polycarbonate. Particularly when solid state polymerization is to be performed, the use of a combination of solvent and non-solvent which produces a crystalline intermediate is performed, and use of a modifying reagent increasing the hydroxy end group concentration of the polycarbonate may be advantageous.

Abstract: Improved thermoplastic compositions comprising a blend of ground vulcanized rubber and olefin polymer which have improved compatibility and mechanical properties are described; they are improved by incorporation of an alpha olefin copolymer.

Abstract: A method for recycling discarded articles comprising sorting the discarded articles into thermoplastic, thermosetting, and rubber articles, crushing the discarded articles to form thermosetting granules, thermoplastic granules, and rubber granules, and depositing the granules into a molding tool. The molding tool is heated under pressure such that the thermoplastic granules melt, and the molding tool is abruptly cooled to cause the molting material to assume a shape in the molding tool.

Abstract: A process and resulting product is provided in which a solid particulate, such as vulcanized crumb rubber, has the surface functional groups oxidized by ozonation using a nonpolar solvent. The ozonation process renders the treated crumb rubber more suitable for use in new rubber formulations. As a result, larger loading levels of the treated crumb rubber can be used in new rubber mixtures.

Abstract: Stable rubberized bitumen concentrates are prepared by initially forming a mass comprising bitumen and crumb rubber particles in an amount of at least about 15 wt % of the mass with the crumb rubber being swollen in-situ, and applying shear and temperature conditions to the mass to dissociate the vulcanizate network of the rubber particles and to incorporate the digested vulcanizate into the bitumen. The stable rubberized bitumen concentrate is stable against sedimentation of rubber particles both following storage of the concentrate at about 320.degree. F. for 48 hours and dilution to a lower concentration in the ASTM solubility test.

Abstract: An improved rubber-modified asphalt paving binder is provided by incorporating a minor proportion of a polyoctenamer into the heated liquid asphalt cement. The binder can contain from about 80% to about 99% by weight of asphalt cement, from about 0.5% to about 20% by weight of crumb rubber, such as ground tire rubber ("GTR"), and from about 0.01% to about 10% by weight of the polyoctenamer. The polyoctenamer can be of the trans- or cis- form, such as that sold under the brand name VESTENAMER.RTM.. A paving concrete is provided by adding the improved asphalt binder, with mixing, to conventional aggregate materials, which materials can also contain additional crumb rubber.

Abstract: The present invention relates to synthetic wood chips and methods for making the same. The synthetic wood chips are made from rubber particles, such as ground up tires, and a colorant which colors the rubber particles to look like natural mulch. The synthetic mulch is available in a wide variety of shapes and sizes, however, it is preferred for the synthetic mulch to look like wood chips, tree bark, or pea gravel.

Abstract: A method of processing used tires and the recovery of the products thereof. The process includes adding shredded automobile tire to a bath containing a combination of isocyanide, polyurethane, latex, and soybean oil. The resultant mixture is then heated at approximately 700.degree. F. for a period of 10 minutes. The process allows the recovery of the following products, including but not limited to: oil, steel, vinyl chloride, carbon, and carbon black. The addition of soybean oil to the bath mixture provides a safer and more economical process. The current process does not require the use of a special atmosphere nor does it require the use of a high pressure system.

Abstract: This invention is based upon the unexpected discovery that cured rubber can be devulcanized by heating it to a temperature of at least about 150.degree. C. under a pressure of at least about 3.4.times.10.sup.6 Pascals in the presence of 2-butanol. The molecular weight of the rubber can be maintained at a relatively high level if the devulcanization is carried out in the presence of the 2-butanol at a temperature of no more than about 300.degree. C. This devulcanization technique does not significantly change the microstructure of the rubber and it can accordingly be used in the same types of applications as was the original rubber. In other words, the devulcanized rubber can be recompounded and recurred into useful articles in substantially the same way as was the original rubber.

Abstract: Tires are converted to rubber particles and inorganic compounds are removed from the tires by treating the tires in a closed reactor with a nitric acid solution having a nitric acid concentration above 60%. In the preferred embodiment, any steel belts contained in the tires are first removed. The tires are then treated with a solution of concentrated nitric acid in which the acid concentration is maintained above 60% which extracts inorganic compounds such as zinc, sulfur and calcium from the tires and converts the tires into rubber particles.

Abstract: A process involving (a) homogeneously dispersing tetrathiodipropionic acid in a recycled rubber having an individual particle size no greater than 420 microns, (b) mixing the treated recycled rubber with unvulcanized rubber and (c) vulcanizing the rubber mixture.

Abstract: Reclaim rubber is obtained from vulcanized rubber by subjecting a mass of the rubber to mechanical working applying highly intensive impact forces to the mass. The process is relatively energy efficient and therefore produces reclaim rubber at relatively low cost. It also mitigates the objectionable smell associated with known reclaim rubber products. The process can be used with the addition of small amounts (usually of the order of 1% to 2% by weight) of various chemicals known to retard cure rates in rubber, but it has been shown to be efficient on a production basis to operate without the addition of, or dependence on, any added chemicals.

Abstract: Processes for spray drying water-soluble and water-swellable vinyl-addition polymer-containing dispersions, emulsions and microemulsions to obtain substantially dry water-soluble or water-swellable polymer particles, compositions of substantially dry water-soluble or water-swellable polymer particles, methods of agglomerating spray-dried polymer particles, and methods of using spray-dried polymer particles and agglomerates in water-treating, mining, paper, food processing, soil conditioning, solution thickening, biotechnological, and oil recovery applications are disclosed.

Abstract: An apparatus (10) for liquefying tires is shown in a first form including a plurality of tire modules (12) holding tires which are immersed in and preheated by a slurry located in a tank (22). After preheating, the tire module (12) and tires held thereon are removed from the preheat tank (22) and are immersed in a slurry located in a high temperature tank (28). The temperature of the slurry in the high temperature tank (28) is sufficient to liquify the tires. As the tires liquify, the slurry produced is retained in the high temperature tank (28) to immerse further tires and also overflows from the high temperature tank (28) to the preheat tank (22) and then to a storage tank (36). The slurry from the storage tank (36) can be pumped to the burner (42) of the heat exchanger (48) for heating the slurry in the high temperature tank (28) or can be used for other purposes.

Abstract: In one embodiment, the present invention relates to a method of separating a coating from a base plastic in a multilayered structure, comprising the steps of (A) providing the multilayered structure comprising at least a coating and a base plastic; (B) contacting the multilayered structure with a mixture comprising (i) a major amount of water, (ii) at least one basic compound or acid compound, (iii) at least one lifting agent, and (iv) at least one accelerator; and (C) separating the coating from the base plastic. In another embodiment, the present invention relates to a separating composition containing a major amount of water, at least one basic compound or acid compound, at least one lifting agent, and at least one accelerator. The inventive methods and compositions overcome numerous problems in the art by enabling the efficient recycling of coated polymer articles whereby clear and/or colorless recycled polymers may be obtained.

Abstract: A waste plastic containing a polymer such as polystyrene polypropylene or ABS resin is dissolved in a solvent to form a solution of the waste plastic at an elevated temperature. The solution is filtered to remove labels or other adhered foreign debris. The filtrate is heated to a temperature of 200.degree.-300.degree. C. under a pressure of 1-75 torrs to remove the solvent by evaporation, and the resulting plastic melt is extruded into pellet whereby the waste plastic is recovered. On the other hand, the solvent separated by the vacuum-evaporation is condensed by a water-, brine- and/or refrigerant-cooled condensers, refined by a vacuum-evaporated and recycled to use it as a solvent for the incoming subsequent waste plastic. The pelleted styrene recycle product is free of debris such as labels and accordingly has a good color. Moreover, this recycle product has a good transparency when the waste plastic is transparent.

Abstract: A pyrolysis batch process is disclosed for recycling hydrocarbon containing used material such as plastics including ABS, polystyrene styrene and other non-chlorinated hydrocarbons, car fluff such as solid plastics, foam plastics, fabrics and the like, and more particularly scrap tires so as to obtain useful light oil and fuel gases. Used tire cuttings are loaded into a rotatable reactor which is closed, evacuated, rotated and heated until exothermic reaction is initiated. The reactor internal pressure is then allowed to increase to and is regulated within the range of atmospheric pressure and above. Upon continuing reactor rotation and heating, condensable hydrocarbon vapors and gaseous hydrocarbons are produced. The vapors are condensed into oil while the gaseous hydrocarbons are used as a fuel for reactor heating.

Abstract: A method of making polymeric particulates wherein polymeric scrap material, virgin polymeric material and mixtures thereof are supplied to intermeshing extruder screws which are rotated to transport the polymeric material along their length and subject the polymeric material to solid state shear pulverization and in-situ polymer compatibilization, if two or more incompatible polymers are present. Uniform pulverized particulates are produced without addition of a compatibilizing agent. The pulverized particulates are directly melt processable (as powder feedstock) and surprisingly yield a substantially homogeneous light color product.

Abstract: A method of preparing an asphalt emulsion composition comprises mixing an aqueous asphalt emulsion, water, latex rubber, and a solids mix composition comprising reclaimed rubber particles passing through a 40 mesh U.S. series sieve and one or more solid addends selected from the group consisting of a rheological agent, gilsonite, carbon black, surface active clay and polymer fibers, and mixtures thereof and wherein the ratio of latex rubber:rubber particles is between about 1:1 and about 1:10, by weight, respectively, and mixing the components at substantially ambient temperature.

Abstract: Waste plastic material is treated so as to make possible its utilization as a binder component in road surfacing materials, as a fuel, or for other desirable purposes. The waste plastic material is made at least partially fluid by mixing it with a solvent. The solvent is waste fats produced in refining or by treating animal and/or vegetable fats, crude fatty acids obtained as byproducts of refining fats, or fatty acids or pitch obtained by distilling hydrolyzed fats. The solvent is typically mixed with waste plastic material in the ratio of less than 1:2, preferably about 1:3, and at a temperature of between about 150.degree.-250.degree. C.

Abstract: A process for devulcanizing and functionalizing a rubber vulcanizate by desulfurization involves suspending a rubber vulcanizate crumb in a solvent which preferably swells the rubber vulcanizate before or during the devulcanization reaction and adding an alkali metal, such as sodium, to the suspension. The alkali metal cleaves mono-, di- and polysulfidic cross-linkages in the rubber vulcanizate to liberate rubber polymer having a molecular weight substantially equal to that of the rubber polymer prior to vulcanization. Functional groups derived from the solvent molecules bond to the devulcanized rubber's polymeric backbone. In addition to the functionalized devulcanized rubber polymer, carbon black may also be recovered for re-use in accordance with the process of the present invention. The functionalized devulcanized rubber may be subjected to a re-vulcanization reaction without separation of rubber polymer from the solvent by addition of an appropriate curing mixture.

Abstract: A composite building material is disclosed produced from recycled materials. The composite building material is composed of an extruded mixture of high density polyethylene and a thermoplastic coated fiber material such as fiberglass. The resulting material has increased strength and is useful in high stress applications such as railroad ties.

Abstract: The invention relates to the technology of reprocessing industrial and domestic waste. The problem addressed is reducing energy consumption and the quantity of toxic waste which enters the environment when rubber waste is reprocessed. This problem is solved by the use of superheated steam for the pyrolysis of the waste material. Superheated steam, amounting to between 18 and 110 percent of the mass of the rubber waste, is used as the heat carrier. The gaseous products of pyrolysis are condensed together with the steam, and the condensate thus obtained is mixed with the solid residue which has first undergone preliminary grinding to produce particles of between 0.001 and 0.210 mm in size. The quantity of solid residue in the mixture is set at between 23 and 55.8 percent of the total mass of the mixture. This process results in the production of a liquid fuel with improved environmental characteristics.

Abstract: Reground rubber from used tires is mixed with a styrene-butadiene copolymer and polypropylene or polyethylene. The mixture is placed under temperatures and pressures to form a plasticized, moldable material, which is then injected into a mold to form sheet material suitable for street signs and other products. Alternatively, acetal resin is substituted for the polypropylene or polyethylene. Alteratively, a moldable product is formed from 75% reground rubber and 25% styrene-butadiene copolymer, which is then combined with ground polypropylene and virgin rubber, in which the combination is comprised of 25% virgin rubber, by weight. The combination is then partially plasticized under temperature and pressure, and then injected into a mold to form sheet material for street signs and other products.

Abstract: A process for the manufacture of devulcanized rubbers from a base material composed of scrap rubber products is provided which produces high grade, low viscosity rubber products. The process is carried out in at least two stages, the first stage comprising mixing a polymeric additive to the base material at elevated temperatures and the second stage comprising mixing unvulcanized virgin rubber with the mixture of base material and polymeric additive at elevated temperatures. The process also may comprise a preliminary stage in which a chemically modified epoxidized natural rubber is mixed with the base material at ambient temperature prior to the first stage.

Abstract: A resin composition useful in well completion and remedial methods having improved flexibility upon setting or curing is disclosed. The resin composition includes a polymerizable resin, an oil soluble acid catalyst capable of causing polymerization of the resin at formation temperatures, and 10 to 70% by volume rubber. The rubber may be in the form of ground rubber or an aqueous dispersion or emulsion. Also disclosed are methods for the use of the resin composition in well completion and remediation.

Abstract: The invention comprises processes for the production of useful fluid or grease from curable silicone compositions or silicone rubbers, preferably reclaimed or scrap silicone rubber. The processes involve the application of energy in such a manner that a un-curable silicone grease or liquid that contains essentially all of the original material is produced from curable silicone compositions and grease or liquid is produced from silicone rubbers. Suitable energy forms include thermal and mechanical. The fluid or grease produced by the processes are useful as raw materials for the manufacture of silicone products such as: antifoam compounds (defoamers), greases, conformal coatings or rubbers. The materials produced by these processes were unexpectedly found to have exceptional antifoam properties without requiring the addition of other materials or further processing.

Abstract: By utilizing the process of the present invention, a free-flowing crumb rubber composition can be easily prepared on a commercial scale. This invention more specifically discloses a process for preparing a free-flowing crumb rubber composition which comprises the steps of:(1) adding a wax emulsion to a latex of a rubbery polymer to produce a latex which contains the wax, wherein the wax has a melting point which is within the range of about 40.degree. C. to about 175.degree. C.;(2) agitating the latex which contains the wax in a manner whereby the wax is distributed throughout the latex;(3) coagulating the latex which contains the wax to produce a slurry of wax coated crumb rubber in water;(4) recovering the wax-coated crumb rubber from the water in the slurry; and(5) drying the wax-coated rubbery polymer in a hot air medium under forced motion to produce the free-flowing crumb rubber composition, wherein the hot air medium is at a temperature which is within the range of about 20.degree. C. to about 99.

Abstract: A modified asphalt composition having improved low-temperature fracture properties is obtained by devulcanizing crumb rubber, preferably ground rubber tire. The devulcanization is effected without the use of harsh oxidizing treatments or the addition of potentially hazardous solvents, by fractional distillation of a mixture of the rubber and crude oil to a temperature at which substantially complete devulcanization occurs and harmful volatiles are driven off, around 300.degree. C. The resulting compositions are relatively inexpensive and simple to produce and, not having been oxidized, may be expected to show better long-term aging and fatigue performance compared to air-blown asphalts and the like. They are also preferable, on grounds of health and safety, to prior paving asphalts containing significant proportions of volatile organic aliphatic or aromatic hydrocarbons.

Abstract: A process for reclaiming cured or semi-cured rubber, by subjecting a mass of rubber to be reclaimed to a solvent effective to swell said mass, passing the formed swollen mass of rubber through restriction means having small openings, such as a perforated plate, deleterious or devulcanizing substances being comprised in at least one of said restriction means and said swollen mass of rubber.

Abstract: A process for producing reclaimed rubber has the steps of: mixing waste vulcanized rubber with unvulcanized new rubber and a devulcanizing agent; and kneading the resulting mixture in a heating atmosphere for mastication of the unvulcanized new rubber and simultaneously reclamation of the waste vulcanized rubber. Furthermore, the obtained unvulcanized reclaimed rubber can be vulcanized with a vulcanizing agent.

Abstract: The invention manufactures mechanical strong objects from a mixture of a plurality of fractions, which together have a high filling grade by accommodating them in plastic, preferably a thermosetter of the low viscosity type. The plastic is preferably resistant against leaching as defined in the Concept Bouwstoffenbesluit, when pollutions in the fractions are present. Finally the invention gives objects with good mechanical properties at low cost price, because of the relatively small use of plastic (to only 8 volume % or less) and the favorable mechanical properties of strongly densified waste, residual or filler materials. Coloring of the objects is possible and the surface can be very smooth. Fibres or residues of fibres containing waste materials can improve the obtained products still further.

Abstract: An improved method is provided for separating acrylonitrile butadiene styrene (ABS) and high impact polystyrene (HIPS) plastics from each other. The ABS and HIPS plastics are shredded to provide a selected particle size. The shredded particles of the ABS and HIPS plastics are applied to a solution having a solution density in a predefined range between 1.055 gm/cm.sup.3 and 1.07 gm/cm.sup.3, a predefined surface tension in a range between 22 dynes/cm to 40 dynes/cm and a pH in the range of 1.77 and 2.05. In accordance with a feature of the invention, the novel method is provided for separating ABS and HIPS, two solid thermoplastics which have similar densities by selectively modifying the effective density of the HIPS using a binary solution with the appropriate properties, such as pH, density and surface tension, such as a solution of acetic acid and water or a quaternary solution having the appropriate density, surface tension, and pH.

Abstract: An elastic paving material includes a mixture of 90-50% by weight of fibrous rubber chips each having a length of 3-30 mm and a diameter of 0.3-3 mm, and 10-50% by weight of crushed pieces of golf balls having a particle size of 3-50 mesh. A curable liquid binder is added so as to bond the fibrous rubber chips and the crushed pieces of golf balls. Another elastic paving material includes only pieces of golf balls having a particle size of 3-50 mesh, and a curable liquid binder is added thereto so as to bond the pieces of golf balls. The crushed pieces of golf balls have a color different from that of the fibrous rubber chips, consist of particles having various colors, or are colored in advance.

Abstract: The invention comprises processes for the production of useful fluid or grease from curable silicone compositions or silicone rubbers, preferably reclaimed or scrap silicone rubber. The processes involve the application of energy in such a manner that a un-curable silicone grease or liquid that contains essentially all of the original material is produced from curable silicone compositions and grease or liquid is produced from silicone rubbers. Suitable energy forms include thermal and mechanical. The fluid or grease produced by the processes are useful as raw materials for the manufacture of silicone products such as: antifoam compounds (defoamers), greases, conformal coatings or rubbers. The materials produced by these processes were unexpectedly found to have exceptional antifoam properties without requiring the addition of other materials or further processing.

Abstract: A depolymerized natural rubber having a number-average molecular weight of from 2,000 to 50,000 obtained by the depolymerization of a deproteinized natural rubber. A process for the preparation of a depolymerized natural rubber comprises dissolving a deproteinized natural rubber into an organic solvent so as to give a concentration of from 1 to 30% by weight and then carrying out air oxidation of the resulting solution in the presence of a metallic catalyst. The depolymerized natural rubber can provide the same physical properties as ordinary vulcanized rubbers, exhibits no odor or color characteristic to natural rubbers and causes no immediate allergy induced by protein.

Abstract: A method of processing used tires and the recovery of the products thereof. The process includes adding shredded automobile tire to a bath containing a combination of isocyanide, polyurethane, latex, and soybean oil. The resultant mixture is then heated at approximately 700.degree. F. for a period of 10 minutes. The process allows the recovery of the following products, including but not limited to: oil, steel, vinyl chloride, and carbon. The addition of soybean oil to the bath mixture provides a safer and more economical process. The current process does not require the use of a special atmosphere nor does it require the use of a high pressure system.

Abstract: An improved floatation separation process wherein the improvement comprises dissolving in a floatation bath sufficient alkali metal salt or alkaline earth metal salt of a phosphate, a pyrophosphate, a metaphosphate or a polyphosphate to provide a concentration greater than 1.0 grams per cubic centimeter and generally about 1.05 to about 1.6. g/cc. A particular salt is sodium dihydrogen phosphate. Preferably, the floatation process is employed to separate physical mixtures of plastic parts.

Abstract: The invention comprises processes for the production of useful fluid or grease from curable silicone compositions or silicone rubbers, preferably reclaimed or scrap silicone rubber. The processes involve the application of energy in such a manner that a un-curable silicone grease or liquid that contains essentially all of the original material is produced from curable silicone compositions and grease or liquid is produced from silicone rubbers. Suitable energy forms include thermal and mechanical. The fluid or grease produced by the processes are useful as raw materials for the manufacture of silicone products such as: antifoam compounds (defoamers), greases, conformal coatings or rubbers. The materials produced by these processes were unexpectedly found to have exceptional antifoam properties without requiring the addition of other materials or further processing.

Abstract: Method of manufacture of paint and adhesive of rubber from vulcanized rubber that is reclaimed, becoming a product that provides impermeability, flexibility and resistance to the pellicle by process of reduction to small particles through cracking beater mills, immersed in adequate solvents and recovered in ball mills to which is added products such as dyeing, pigments, asphalts, oils, accelerators, resins, etc., which give to the paint or adhesive its final characteristics.

Abstract: A dry liquid concentrate mixture is disclosed comprising crumb rubber particles and tall oil, tall oil derivatives or other fatty acids, which may be enhanced by other components, such as modifiers, for use to enhance the properties of parent materials, such as thermoplastic compounding and coatings and elastomers and recycles and asphalt and epoxies and aliphatic urethane.

Abstract: A process for devulcanizing a rubber vulcanizate by desulfurization involves suspending a rubber vulcanizate crumb in a solvent which preferably swells the rubber vulcanizate before or during the devulcanization reaction and adding an alkali metal, such as sodium, to the suspension. The alkali metal cleaves mono-, di- and polysulfidic cross-linkages in the rubber vulcanizate to liberate rubber polymer having a molecular weight substantially equal to that of the rubber polymer prior to vulcanization. Carbon black may also be recovered for re-use in accordance with the process of the present invention. Devulcanized rubber may be subjected to a re-vulcanization reaction without separation of rubber polymer from the solvent by addition of an appropriate curing mixture.

Abstract: The invention is a method of using enzymes from thiophyllic microbes for selectively breaking the sulfur rubber cross-link bonds in vulcanized rubber. The process is halted at the sulfoxide or sulfone step so that a devulcanized layer is reactive with virgin rubber.

Abstract: A process for preparing a homogenous asphalt composition includes introducing distillation tower bottoms at a temperature of about 425.degree.-470.degree. F. to a vessel through which air is flowing at about 6-15 psi pressure, introducing ground tire rubber to the vessel and bombarding the distillation tower bottoms and ground tire rubber with the air until the mixture is completely and stably homogenized, and recovering the homogenized asphalt composition. The homogenized asphalt composition is a two-component composition of distillation tower bottoms and ground tire rubber abrasively absorbed therein.

Abstract: The invention provides an apparatus and method of its use, for recovering either devulcanized rubber or purified carbon and volatiles from a crumb rubber feed material. The apparatus comprises a chamber; a vacuum pump for providing reduced pressure within the chamber; an inlet for feeding crumb rubber into the chamber; an auger for providing continuous movement of the crumb rubber though the chamber; a battery of microtrons for providing substantially precise energy input into the crumb rubber as it is continuously moved through the chamber by the auger; at least one condenser for recovering volatiles from the crumb rubber after it has been sufficiently heated by said the microtrons; and an outlet for withdrawing either a devulcanized rubber or a purified carbon product residue from the chamber.

Abstract: There are provided a deproteinized natural rubber latex which comprises a purified product of proteolytically treated natural rubber latex and contains fine particles of natural rubber latex, a deproteinized natural rubber which comprises a dehydrated product of the deproteinized natural rubber latex, and a process for the production of deproteinized natural rubber latex which comprises subjecting a latex solution prepared by (1) adding water and/or a surfactant to a natural rubber latex and then proteolytically treating the resulting latex solution or (2) proteolytically treating a natural rubber latex and then adding water and/or a surfactant to the treated natural rubber latex, to purification using a rotary plate membrane separation apparatus.

Abstract: A rubber compound obtained by compounding a raw rubber, powdered vulcanized scrap rubber with its surface partially processed via a swelling treatment, a vulcanizing agent and a vulcanizing accelerator. When manufacturing the compound, the scrap rubber is treated beforhand under ordinary temperature atomosphere by being mixed with a reclaiming agent that contains petroleum process oil.

Abstract: A method of preparing an asphalt emulsion-rubber paving composition comprises combining an aqueous asphalt emulsion, water, latex rubber, minus 40 size rubber particles, and a thickening agent, mixing said materials at substantially ambient temperature to form a substantially homogeneous liquid composition, adding to said liquid composition between about 5 and about 15 pounds of aggregate per gallon of said gallon, and mixing the components at substantially ambient temperature to form such paving composition.