Firestone Tire and Rubber Company

Figure 12.30 Potential uses of polyphosphazenes (a) A thin film of a poly(aminophosphazene) sueh materials are of interest for biomedical applications, (b) Fibres of poly[bis(trifluoroethoxy)phosphazene] these fibres are water-repellant, resistant to hydrolysis or strong sunlight, and do not burn, (c) Cotton cloth treated with a poly(fluoroalkoxyphosphazene) showing the water repellaney eonferred by the phosphazene. (d) Polyphosphazene elastomers are now being manufaetured for use in fuel lines, gaskets, O-rings, shock absorbers, and carburettor eomponents they are impervious to oils and fuels, do not bum, and remain flexible at very low temperatures. Photographs by eourtesy of H. R. Allcock (Pennsylvania State University) and the Firestone Tire and Rubber Company.

Prakash D. Trivedi present address Central Research Laboratories, The Firestone Tire and Rubber Company, Akron, Ohio 44317, U.S.A. 

Acknowledgements. The authors are grateful to Drs. D. McIntyre and S. Shih of The University of Akron for the fractionated PIB samples. Financial help by the National Science Foundation and the Firestone Tire and Rubber Company is gratefully acknowledged. 

Acknowledgements. Financial help by the National Science Foundation and the Firestone Tire and Rubber Company is gratefully acknowledged. 

Allcock s discovery that stable polyphosphazenes could be prepared under controlled conditions opened the door for the commercial development of this class of polymers, and In 1970, the first polyphosphazene elastomers were synthesized and the technology subsequently developed by Firestone Tire and Rubber Company (5). Today, polyphosphazenes are commercially available, and represent... 

A number of the giant tire companies started at the turn of the century. In America many of these companies centered around Akron, the capital of the rubber tire. In 1898 the Goodyear Tire and Rubber Company started. The Firestone Tire and Rubber Company was started by Harvey Firestone in 1900. Other tire companies shortly followed. 

The author wishes to thank The Firestone Tire and Rubber Company for permission to publish these results. 

Figure 3.1 Polyphosphazene elastomers of general formula, [NP(OCH2CF3) (OCH2(CF2), CF2H)]b, fabricated into fuel lines, O-rings, gaskets, and other hydrocarbon-resistant devices. Reproduced by permission of the Firestone Tire and Rubber Company, and Ethyl Corporation.

In 1955 investigators from the Firestone Tire and Rubber Company and the B. F. Goodrich Company announced the synthesis of polyisoprene with over 90 percent cis-1,4 structure. The work at Firestone was based on lithium metal catalysts, whereas the work at Goodrich was the result of using Ziegler-Natta type coordination catalysts.22,23... 

The discovery of the ability of lithium-based catalysts to polymerize isoprene to give a high cis 1,4 polyisoprene was rapidly followed by the development of alkyllithium-based polybutadiene. The first commercial plant was built by the Firestone Tire and Rubber Company in 1960. Within a few years the technology was expanded to butadiene-styrene copolymers, with commercial production under way toward the end of the 1960s. 

Medium-c/5 lithium-polybutadiene was first developed by Firestone Tire and Rubber Company in 1955 [86]. Solution polymerization using anionic catalysts is usually based on butyllithium. Alkyllithium initiation does not have the high stereospecificity of the coordination catalysts based on titanium, cobalt, nickel, or neodymium compounds. Polymerization in aliphatic hydrocarbon solvents such as hexane or cyclohexane yields a polymer of about 40 % cis, 50 % trans structure with 10 % 1,2-addition. However, there is no need for higher cis content because a completely amorphous structure is desired for mbber applications the glass transition temperature is determined by the vinyl content. The vinyl content of the polybutadiene can be increased up to 90 % by addition of small amounts of polar substances such as ethers. 

All solvents and monomers were purified and stored under nitrogen atmosphere. The r-butyl chloride (r-BuCl, Eastman) was distilled from calcium hydride under nitrogen atmosphere prior to use. Diethylaluminum chloride (Et2 A1C1, Texas Alkyls Co.) was purified by vacuum distillation (bp °C/mm Hg 110/25). Ethyl chloride (EtCl, Linde Division, Union Carbide Co.) was purified by passing through a column packed with Molecular Sieves and barium oxide. The m-3-hexene (Chemical Samples Company) was distilled under nitrogen prior to use. The polybutadiene, Diene 35, from the Firestone Tire and Rubber Company and high 1,2-polybutadiene were purified by reprecipitations from benzene into excess acetone. 

Appellate Court of the State of California, Potter v. Firestone Tire and Rubber Company SOI18831,... 

The authors are grateful to M. L. Stayer, T. A. Antkowiak, and T. C. Cheng for the synthesis of the fluoroelastomer used in this study. We also wish to thank The Firestone Tire and Rubber Company which made this research possible and encouraged the publication of this study. 

Firestone Tire and Rubber Company, Akron 17, Ohio, t E. I. du Pont de Nemours and Company, Wilmington, Del. 

Alkali Metals The direct use alkali metals and alkaline-earth metals as initiators for anionic polymerization of diene monomers as first reported in 1910 is primarily of historical interest because these are uncontrolled, heterogeneous processes [4]. One of the most significant developments in anionic vinyl polymerization was the discovery reported in 1956 by Stavely and coworkers at Firestone Tire and Rubber Company that polymerization of neat isoprene with lithium dispersion produced high di-l,4-polyisoprene, similar in structure and properties to Hevea natural rubber [47]. This discovery led to development of commercial anionic solution polymerization processes using alkyllithium initiators. 

Hydrocarbon Solvents One of the most important synthetic and commercial aspects of anionic polymerization is the ability to prepare polydienes [poly(l,3-dienes)] with high 1,4-microstructure using lithium as the counterion in hydrocarbon solutions [3, 156]. The key discovery was reported in 1956 by scientists at the Firestone Tire and Rubber Company that polyisoprene produced by lithium metal-initiated anionic polymerization had a high (>90%) cm-1,4-microstructure similar to natural rubber [47], In general, conjugated 1,3-dienes [CH2=C(R)-CH=CH2] can polymerize to form four constimtional isomeric microstructures as shown below. The stereochemistry of the anionic polymerization of isoprene and... 

Figure 8. Aryloxyphosphazene elastomers (APN) offer excellent potential for applications such as A, closed cell foam thermal insulation with high fire retadancy and low smoke generation (32.34) B, pigmented APN coatings in aluminum substrates with low flanmablllty, low flame spread, and low smoke (35) C, APN Insulation and cable Jacketing (36) D, open cell APN comfort cushioning (37). Photograph courtesy of Firestone Tire and Rubber Company ( ).

PRODUCERS AND/OR SUPPLIERS Anic Bayer Bunawerke Huels Bridgestone/Firestone Tire and Rubber Company Goodyear Tire and Rubber Company MicheUn. ... 

Just a few miles south of Brecksville, the chemists at the Firestone Tire and Rubber Company in Akron were investigating... 

Dr. G. G. A. Bohm of the Firestone Tire and Rubber Company. Sample characterization data are shown in Table I. 

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. 

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