Phillips Butadiene rubber

Philprene Sytrene-Butadiene rubber Phillips Petroleum... 

Retrospective View of Vinyl-BR Properties In the 1950s, the Phillips Petroleum Company and the Firestone Tire and Rubber Company started commercial production of polybutadienes by organolithium polymerization for use in tyres. These solution BRs, having low vinyl contents (8-10%), were used in blends with emulsion SBR in tyre treads for balancing traction and wear performance properties. In the early 1970s when styrene monomer was in short supply, developments from Phillips Petroleum Company and EniChem (formerly the International Synthetic Rubber Company) showed that vinyl-BRs with 50-55% vinyl content behaved like emulsion polymerized SBR in tyre tread formulations and exhibited very similar tread wear and wet skid resistance. Tread compounds containing 45%-vinyl polybutadiene showed lower heat build-up and better blow-out resistance than E-SBR and blends of E-SBR with cw-BR. EniChem introduced trial quantities of a medium-vinyl butadiene rubber (MVBR) under the name Intolene 50 in 1973. 

Philprene Styrene-butadiene rubber Phillips Petroleum Co. 

Closely related to these but thermoplastic rather than rubber-like in character are the K-resins developed hy Phillips. These resins comprise star-shaped butadiene-styrene block copolymers containing about 75% styrene and, like SBS thermoplastic elastomers, are produced by sequential anionic polymerisation (see Chapter 2). 

Transparent block copolymers of styrene and butadiene, having polystyrene character (Phillips). Weather-resistant, impact-resistant polystyrene with EPDM rubber (Mitsui Toatsu, Hoechst). 

As of this date, there is no lithium or alkyl-lithium catalyzed polyisoprene manufactured by the leading synthetic rubber producers- in the industrial nations. However, there are several rubber producers who manufacture alkyl-lithium catalyzed synthetic polybutadiene and commercialize it under trade names like "Diene Rubber"(Firestone) "Soleprene"(Phillips Petroleum), "Tufdene"(Ashai KASA Japan). In the early stage of development of alkyl-lithium catalyzed poly-butadiene it was felt that a narrow molecular distribution was needed to give it the excellent wear properties of polybutadiene. However, it was found later that its narrow molecular distribution, coupled with the purity of the rubber, made it the choice rubber to be used in the reinforcement of plastics, such as high impact polystyrene. Till the present time, polybutadiene made by alkyl-lithium catalyst is, for many chemical and technological reasons, still the undisputed rubber in the reinforced plastics applications industries. 

Van Henten, at the Shell Plastic Laboratories (II), showed that styrene-butadiene block polymers can be blended with commercial HIPS to upgrade its impact strength to 5.8 ft-lbs/inch. Childers, at Phillips Petroleum (12), blended commercial polystyrene with block polymers in a Brabender plastograph. To control rubber particle size he added a peroxide during the blending operation, thereby creating crosslinks. With this technique he achieved an impact strength of 5.9 ft-lbs/inch. 

Beaton, Enterprise in Oil, p. 575. The synthetic rubber Buna program based on butadiene was much smaller than the 100-octane project. See ibid., pp. 592-598 Larson and Porter, History of Humble Oil, pp. 597-600. Again, Shell, Jersey Standard, and Phillips were the leading players. 

Styrene-butadiene block copolymers (SBC) with a high (70-85 %) styrene content are commercially produced and marketed as transparent, stiff, and tough thermoplastic resins under the trade names of Styrolux (Styrolution), K-Resin (Chevron-Phillips), Finaclear (Total petrochemical), and Clearene (Denka-Kaguku). Unlike other more elastomeric types of styrene-butadiene block copolymers, the rigid SBC resins contain only <25 % polybutadiene rubber content. Structurally, these SBC polymers are composed of polystyrene (S) and polybutadiene (B) blocks, linked together in an unsymmetrical star-block [(S-B)x] structure. 

Rubber grade 1,3-butadiene was purchased from the Phillips Petroleum Company. Two columns, one packed with the potassium form of a sulfonic acid ion exchange resin (Dowex MSC-l-K) and the other packed with an activated alumina, were used to purify the butadiene. Isoprene was purchased from Aldrich Chemical Company. Stabilizer-free styrene monomer was obtained directly from the Dow styrene monomer plant. Alpha-methylstyrene (AMS) was purchased from U.S. Steel Corporation. The last three monomers were all purified by passing through a column packed with activated alumina and then vacuum distilled over calcium hydride. 

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