Abstract: The process and catalyst system of this invention can be utilized to synthesize a highly random styrene-butadiene rubber having a high trans content by solution polymerization. The styrene-butadiene rubber made by the process of this invention can be utilized in tire tread rubbers that exhibit improved wear characteristics. This invention more specifically reveals a catalyst system for use in exothermal polymerizations which consists essentially of (a) an organolithium compound, (b) a barium alkoxide and (c) a lithium alkoxide. The subject invention further discloses a process for synthesizing a random styrene-butadiene rubber having a low vinyl content by a process which comprises copolymerizing styrene and 1,3-butadiene under isothermal conditions in an organic solvent in the presence of a catalyst system which consists essentially of (a) an organolithium compound, (b) a barium alkoxide and (c) a lithium alkoxide.

Abstract: This invention reveals steel alloys for use in manufacturing reinforcing wires for rubber products, such as tires. The steel filaments made with such steel alloys have an outstanding combination of strength and ductility. The steel alloys of this invention can be manufactured into filaments having a tensile strength in the range of 4000 MPa to 5000 MPa. Additionally, these can be patented in a low-cost process due to their having a very fast rate of isothermal transformation. This allows the steel in the steel wire being patented to transform from a face-centered cubic microstructure to an essentially body-centered cubic microstructure within a very short period. This invention more specifically discloses a steel alloy composition which is particularly suitable for use in manufacturing reinforcing wire for rubber products which consists essentially of (a) iron, (b) about 1.05 to about 1.7 weight percent carbon, (c) about 0.2 to about 0.8 weight percent manganese, (d) about 0.1 to about 0.

Abstract: The subject invention relates to a process for coating aggregate which is particularly useful in making asphalt concrete to provide the aggregate with a high level of resistance to stripping by water, which comprises: (1) mixing the aggregate with latex to form a latex/aggregate mixture, wherein said latex is comprised of water, an emulsifier, a polymer and a water-soluble divalent metal salt; (2) heating the latex/aggregate mixture to a temperature which is within the range of about 66.degree. C. to about 232.degree. C.; (3) maintaining the latex/aggregate mixture at said elevated temperature for a time which is sufficient to reduce the moisture content of the latex/aggregate mixture below about 0.7 weight percent and to allow the polymer in the latex to crosslink on the surface of the aggregate to produce the coated aggregate.

Abstract: Hoses are often reinforced with fabric to improve their performance characteristics, such as burst strength. For instance, radiator hose used in automotive applications is generally reinforced with continuous yarn. However, it is a labor-intensive process to manufacture such hoses which include fiber reinforcements. A substantial amount of material waste also generally occurs in the manufacture of such fiber-reinforced hose. By utilizing the technique of this invention, hose which has a high level of burst strength can be manufactured without including continuous yarn reinforcement.

Abstract: This invention discloses a rubbery polymer having improved properties which is comprised of repeat units which are derived from (a) butyl acrylate, or optionally a mixture of butyl acrylate and 2-ethylhexyl acrylate containing up to about 40 percent 2-ethylhexyl acrylate, (b) at least one member selected from the group consisting of methyl methacrylate, ethyl methacrylate, methyl acrylate and ethyl acrylate, (c) acrylonitrile, (d) styrene and (e) a crosslinking agent; wherein a chemical agent or a copolymer containing hydroxyl groups, ester groups, amine groups or carboxylic acid groups is grafted onto said rubbery polymer. The grafting can be done in the presence or in the absence of a carrying polymer matrix which should be inert with regard to the grafting reaction. Fatty alcohols and ethylene vinyl acetate are representative examples of agents which can be grafted onto the rubbery polymer.

Abstract: This invention relates to a tire tread compound that is easily processable which can be used to improve the treadwear, rolling resistance and traction characteristics of tires. The tire tread compounds of this invention are a blend of tin-coupled polybutadiene, high vinyl polybutadiene and natural rubber. This blend of low glass transition temperature rubber and high glass transition temperature rubber is surprisingly easy to process which makes the concept of this invention commercially feasible. Thus, the tire tread compounds of this invention can be utilized in making tires having greatly improved traction characteristics and treadwear without sacrificing rolling resistance. These improved properties may be due, in part, to better interaction and compatibility with carbon black and/or silica fillers. The polybutadiene in the blend can be asymmetrical tin-coupled to further improve the cold flow characteristics of the rubber blend.

Abstract: There is a need for polymers which are utilized in automotive interiors which offer increased heat and ultraviolet light resistance. It is particularly critical for polymers which are utilized in making skin compounds for automotive instrument and door panels to display excellent heat and ultraviolet light resistance. This invention discloses a continuous process for preparing a rubbery polymer which can be blended with polyvinyl chloride to make leathery compositions having good heat and ultraviolet light resistance. This technique involves utilizing a multiple continuous reactor system wherein a first phase monomer solution containing butyl acrylate, an acrylic monomer, acrylonitrile and a crosslinking agent is continuously charged into at least three initial reactors. To attain a small particle size, it is necessary to limit the solids content in each of these initial reactors.

Abstract: This invention discloses a process for preparing an asymmetrical tin-coupled rubbery polymer which comprises: (1) continuously polymerizing in a first reactor at least one diene monomer to a conversion of at least about 90 percent, utilizing an anionic initiator to produce a polymer cement containing living polydiene rubber chains; (2) continuously feeding the polymer cement produced in the first reactor into a second reactor; (3) adding a tin halide to the polymer cement in a second reactor under conditions of agitation to produce a polymer cement having the tin halide homogeneously dispersed therein, wherein the residence time in the second reactor is within the range of about 15 minutes to about 4 hours; (4) continuously feeding the polymer cement having the tin halide homogeneously dispersed therein into a plug flow reactor having a residence time of about 15 minutes to about 1 hour to produce a polymer cement of the asymmetrically tin-coupled rubbery polymer; and (5) continuously withdrawing the polymer

Abstract: By utilizing the vapor phase polymerization techniques of the present invention, numerous distinct and highly beneficial advantages are realized. For instance, cis-1,4-polyisoprene rubber and high cis-1,4-polybutadiene rubber having a consistent and controllable molecular weight can be easily and practically prepared without utilizing a solvent. The subject invention more specifically discloses a method for vapor phase polymerizing isoprene into cis-1,4-polyisoprene in a process comprising the steps of:(1) charging into a reaction zone said isoprene and a preformed catalyst system which is made by reacting an organoaluminum compound with titanium tetrachloride, preferably in the presence of at least one ether; wherein the isoprene is maintained in the vapor phase in said reaction zone by a suitable combination of temperature and pressure;(2) allowing said isoprene to polymerize into cis-1,4-polyisoprene at a temperature within the range of about 35.degree. C. to about 70.degree. C.

Abstract: This invention is based upon the unexpected discovery that aliphatic solvents and secondary plasticizers act to reduce the viscosity of plastisol compositions that contain a crosslinked nitrile rubber. It has been unexpectedly found that plastisol compositions having acceptable viscosities which contain more than 30 or even 40 percent crosslinked nitrile rubber can be made by incorporating an aliphatic solvent or an aliphatic plasticizer therein.

Abstract: Tire rubbers which are prepared by anionic polymerization are frequently coupled with a suitable coupling agent, such as a tin halide, to improve desired properties. It has been unexpectedly found that greatly improved properties for tire rubbers, such as lower hysteresis, can be attained by asymmetrically coupling the rubber.

Abstract: This invention relates to a tire tread compound that is easily processable which can be used to improve the treadwear, rolling resistance and traction characteristics of tires. The tire tread compounds of this invention are a blend of tin-coupled polybutadiene, high vinyl polybutadiene and natural rubber. This blend of low glass transition temperature rubber and high glass transition temperature rubber is surprisingly easy to process which makes the concept of this invention commercially feasible. Thus, the tire tread compounds of this invention can be utilized in making tires having greatly improved traction characteristics and treadwear without sacrificing rolling resistance. These improved properties may be due, in part, to better interaction and compatibility with carbon black and/or silica fillers. The polybutadiene in the blend can be asymmetrical tin-coupled to further improve the cold flow characteristics of the rubber blend.

Abstract: This invention relates to a tire tread compound that is easily processable which can be used to improve the treadwear, rolling resistance and traction characteristics of tires. The tire tread compounds of this invention are a blend of tin-coupled polybutadiene, high vinyl polybutadiene and natural rubber. This blend of low glass transition temperature rubber and high glass transition temperature rubber is surprisingly easy to process which makes the concept of this invention commercially feasible. Thus, the tire tread compounds of this invention can be utilized in making tires having greatly improved traction characteristics and treadwear without sacrificing rolling resistance. These improved properties may be due, in part, to better interaction and compatibility with carbon black and/or silica fillers. The polybutadiene in the blend can be asymmetrical tin-coupled to further improve the cold flow characteristics of the rubber blend.

Abstract: Various benefits can be attained by utilizing trans-1,4-polybutadiene in tire rubber compounds. For instance, the green strength of tire rubber compounds can be improved by including trans-1,4-polybutadiene therein. The inclusion of trans-1,4-polybutadiene in tire rubber compounds is also beneficial because it is strain crystallizable. However, due to its high melting point, it is normally necessary to heat trans-1,4-polybutadiene in order for it to be processed using conventional mixing equipment. This heating step is typically carried out by storing the trans-1,4-polybutadiene in a "hothouse" for a few days prior to its usage. During this storage period, the polymer typically undergoes undesirable oxidative crosslinking which is caused by residual cobalt catalyst and leads to gelation. In fact, the gelation can render the trans-1,4-polybutadiene unprocessable.

Abstract: This invention discloses an aqueous slurry for coating the surface of rubber slabs or pellets to reduce the tendency of the rubber slabs or pellets to stick together, said aqueous slurry being comprised of (1) from about 1 weight percent to about 15 weight percent of syndiotactic-1,2-polybutadiene having a melting point of no more than about 140.degree. C. and a particle size of no more than about 40 mesh; (2) from about 0.1 weight percent to about 5 weight percent of a suspending agent; (3) from about 0.05 weight percent to about 2 weight percent of a wetting agent; and (4) from about 78 weight percent to about 98 weight percent water. The present invention further reveals a coated rubber slab having resistance to sticking which is comprised of a rubber slab having a coating thereon, wherein said coating is comprised of syndiotactic-1,2-polybutadiene having a melting point of no more than about 140.degree. C. and a particle size of no more than about 40 mesh.

Abstract: This invention is based upon the unexpected discovery that uintahite can be incorporated into tire component rubber to improve the physical properties thereof. For example, by incorporating uintahite into tire tread rubber compositions, tires with improved tear and puncture resistance can be manufactured. Since uintahite is a relatively low cost material, its incorporation into tires also reduces cost. For instance, uintahite can be incorporated into a wide variety of tire rubber compounds used in the tread (including the base and the cap), sidewall, apex, chafer, bead coat, toeguard, innerliner, ply coat, gum strips, coverstrip, overlay and wedge stocks.

Abstract: This invention relates to a tire tread compound that can be used in manufacturing tires having outstanding traction characteristics without compromising treadwear and rolling resistance. The tire tread compounds of this invention are made utilizing an isoprene-butadiene rubber having a high glass transition temperature and having SnR.sub.3 end groups, wherein R represents an alkyl group, such as a tertiary-butyl group. These isoprene-butadiene rubbers are made by reacting an isoprene-butadiene rubber having a glass transition temperature which is within the range of about -50.degree. C. to about 0.degree. C. with a tin compound of the formula SnR.sub.3 X, wherein R represents an alkyl group and wherein X represents a halogen. This invention more specifically discloses a tire tread rubber composition which is comprised of (1) about 60 phr to about 95 phr of an isoprene-butadiene rubber having a glass transition temperature which is within the range of about -50.degree. C. to about 0.degree. C.

Abstract: This invention relates to a polymeric composition having ultraviolet light and heat resistance that can be molded into rubbery articles that can be magnetized. For instance, the rubbery compositions of this invention can be molded into magnetic seals for refrigerator or freezer doors. In such applications, the magnetic composition acts as a combination airtight gasket and magnetic closure device for the refrigerator or freezer. These polymeric magnetic compositions offer the advantage of being thermoplastic materials rather than thermosets. By virtue of being thermoplastics, they can be injection-molded into the desired form without the need for a curing step. Thus, rubbery magnetic compositions can be manufactured by a simpler, less costly process by utilizing the compositions of this invention.

Abstract: The present invention relates to a high clarity water sensitive carboxylated nitrile rubber composition which is particularly useful in making photopolymer formulations for printing plates utilized in flexographic printing applications. The present invention more specifically discloses a high clarity water sensitive carboxylated nitrile rubber composition which is comprised of (a) a carboxylated nitrile rubber which is comprised of repeat units which are derived from about 30 weight percent to about 60 weight percent 1,3-butadiene, from about 30 weight percent to about 50 weight percent acrylonitrile, and from about 10 weight percent to about 20 weight percent methacrylic acid, and (b) from about 1 to about 10 phr of at least one organic acid which contains at least three carboxyl groups. The carboxylated nitrile rubber of this invention will typically have a Mooney ML-4 viscosity of less than about 80.

Abstract: Syndiotactic 1,2-polybutadiene is a thermoplastic resin which has double bonds attached in an alternating fashion to its polymeric backbone. Films, fibers and molded articles can be made utilizing syndiotactic 1,2-polybutadiene. It can also be blended into rubbers and cocured therewith. In such applications, sometimes it is beneficial for the syndiotactic 1,2-polybutadiene to have more than one melting point. This invention discloses a process for preparing syndiotactic 1,2-polybutadiene having at least two different melting points which comprises: polymerizing 1,3-butadiene monomer in an aqueous medium in the presence of (1) a catalyst composition which is made by reacting (a) at least one cobalt compound selected from the group consisting of (i) .beta.-diketone complexes of cobalt, (ii) .beta.-keto acid ester complexes of cobalt, (iii) cobalt salts of organic carboxylic acids having 6 to 15 carbon atoms and (iv) complexes of halogenated cobalt compounds of the formula CoX.sub.