Patent GB-968756-A (GB)
Title: Butadiene polymer and blends and compositions containing same
IPC: C08F36/04
Filed: 1962-08-24
Abstract: 968,756. Rubbery butadiene copolymers and graft polymers thereof. FIRESTONE TIRE & RUBBER CO. Aug. 24, 1962 [Aug. 25, 1961; Feb. 2, 1962; July 27, 1962], No. 32577/62. Headings C3B, C3G, C3P and C3R. Modified rubbery stereospecific polybutadienes containing not more than 15% gel comprise either (A) a polymer of butadiene and from 0À025 to 0À4 parts per 100 parts of total monomer weight of a comonomer having at least two terminal non-conjugated CH=CH 2  groups or (B) a polymer of butadiene, a first comonomer which is a compound having a single terminal C=CH 2  group or which is a compound having conjugated terminal C=CH 2  groups and from 0À025 to 0À4 parts per 100 parts of total monomer weight of a modifying comonomer having at least two terminal non-conjugated CH=CH 2  groups. In either case the polybutadiene portion of the rubbery polymer contains 30 to 100% cis-1,4 structure, a total 1,4-structure of at least 85% and not in excess of 12% 1,2-structure. Modifying comonomers may be aliphatic, aromatic, cyclic, acyclic or heterocyclic; the preferred compounds include the benzenes, xylenes, anthracenes, naphthalenes and durenes substituted by two or more vinyl groups. Other aromatic and aliphatic modifying comonomers mentioned are bis (4,41-vinyl) azobenzene; bis- (4,4<SP>1</SP>-vinylphenyl) ether; bis (4,41-vinyl phenyl) sulphide; bis (4,4<SP>1</SP>-vinylphenyl) disulphide; bis- (4,4<SP>1</SP>-vinylphenyl) amine; tris (4,4<SP>1</SP>,4<SP>11</SP>-vinylphenyl) amine; divinyl acetylene, diacetylene and triacetylene; diallyl acetylene, diacetylene and triacetylene; diallyl, azodiallyl, divinyl, trivinyl and triallyl phosphates and phosphites, and ethylene dimethacrylate. Monomeric compounds having a single terminal C=CH 2  group or conjugated terminal C=CH 2  groups listed are styrene and substituted styrenes, vinyl pyridine, vinyl and allyl naphthalene, isobutene, acrylonitrile, allyl benzene and toluene, isoprene, propylene and halogen-substituted derivatives of the above. The rubbery polymers of the invention may be oil-extended, the plasticizer or extension oils being those conventionally used. In addition liquid low molecular weight polymers may be used, as well as aromatic oils. Reinforcing pigments such as zinc oxide and carbon blacks are used in the oil-extended or plasticized polymers. The polymers of the invention may be blended with polystyrene, phenoplasts, aminoplasts, epoxy resins, natural rubber, SBR rubber, butadiene-acrylonitrile copolymers, stereospecific rubbery polyisoprene, stereospecific butadiene homo- and co-polymers and ethylene-propylene copolymers. Graft polymers may be formed from the poly-butadienes of the invention by subjecting the latter to polymerizing conditions in the presence of one or more olefinic materials such as vinyl chloride, styrene or a substituted styrene, acrylates and methacrylates and vinyl fluoride. In the examples butadiene is copolymerized with divinyl benzene using butyl lithium as catalyst and hexane as solvent, and the copolymers, blended with other rubbery materials if desired, and compounded with the usual ingredients, may be used in vehicle tyres. Specifications 737,086, 817,693, 827,365, 848,065 and 960,194 are referred to.