Firestone Tire and Rubber

The use of alkaU metals for anionic polymerization of diene monomers is primarily of historical interest. A patent disclosure issued in 1911 (16) detailed the use of metallic sodium to polymerize isoprene and other dienes. Independentiy and simultaneously, the use of sodium metal to polymerize butadiene, isoprene, and 2,3-dimethyl-l,3-butadiene was described (17). Interest in alkaU metal-initiated polymerization of 1,3-dienes culminated in the discovery (18) at Firestone Tire and Rubber Co. that polymerization of neat isoprene with lithium dispersion produced high i7j -l,4-polyisoprene, similar in stmcture and properties to Hevea natural mbber (see ELASTOLffiRS,SYNTHETic-POLYisoPRENE Rubber, natural). 

Applications. Among the P—O- and P—N-substituted polymers, the fluoroalkoxy- and aryloxy-substituted polymers have so far shown the greatest commercial promise (14—16). Both poly[bis(2,2,2-trifluoroethoxy)phosphazene] [27290-40-0] and poly(diphenoxyphosphazene) [28212-48-8] are microcrystalline, thermoplastic polymers. However, when the substituent symmetry is dismpted with a randomly placed second substituent of different length, the polymers become amorphous and serve as good elastomers. Following initial development of the fluorophosphazene elastomers by the Firestone Tire and Rubber Co., both the fluoroalkoxy (EYPEL-F) and aryloxy (EYPEL-A) elastomers were manufactured by the Ethyl Corp. in the United States from the mid-1980s until 1993 (see ELASTOLffiRS,SYNTHETic-PHOSPHAZENEs). 

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. 

S. H. Rose in 1968 [263, 265] first described the reaction of polydichloro-phosphazene with trifluoroethoxy groups coupled with a second fluorinated alkoxy residue of longer chain. During the successive twenty years they were deeply investigated by Horizon Inc. [263, 265, 502-506, 518, 544, 552-554], AMMRC [396, 452, 555-557], NASA [517, 522, 523], The Firestone Tire and Rubber [393,519,528,530,533,558,559], and Ethyl Co. [507,560,561] for the applications described above (vide supra). 

Hergenrother WL, Fieldhouse JW,HalasaAF (1986) US US,4,623,525,Chem Abstr 106, 50874r (1987), assigned to The Firestone Tire and Rubber Co... 

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... 

Randomly - Crosslinked PB and PI. Polybutadiene (Diene 35 NFA, Firestone Tire and Rubber Co.) and cis-polyisoprene (Natsyn 2200, Goodyear Tire and Rubber Co.) were crosslinked with dicumyl-peroxide, as for PDMS. Mc values were also calculated by means of equation 2. They are given for PI in Table I and are listed for PB in reference 2. 

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 financial support of the symposium by The Firestone Tire and Rubber Co., Gulf Oil Chemicals Co., the 3M Co., the Shell Development Co., and the Polymer Materials and Interfaces Laboratory of our University was extremely helpful. 

V. D. MOCHEL—The Firestone Tire and Rubber Co., Central Research Laboratories, Akron, OH 44317... 

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

Supplied by D. C. Smith, Phillips Petroleum Co., Bartlesville, Okla. c Supplied by J. L. Binder, Firestone Tire and Rubber Co., Akron, Ohio. 

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... 

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