Adiprene

Another approach has been adopted by the Du Pont Company with Adiprene C. This is a urethane-type polymer with unsaturated groups in the polymer. Because of the unsaturation the polymer may be vulcanised with sulphur, the standard vulcanising agent of the rubber industry. This is a clear-cut example of a product being modified to suit the processor rather than that of a processor adapting himself to meet new products. Whereas Adiprene C has poor tensile strength when unfilled, the use of carbon black leads to appreciable reinforcement (as is the case with SBR and to some extent natural rubber. 

Isocyanates. The most common isocyanates encountered in polyurethane propellants are 2,4-tolylene diisocyanate, TDI, and hexamethyl-ene diisocyanate, HDI. 3-Nitrazapentane diisocyanate has also been used in high density propellants. In some polyurethane liners Adiprene L (duPont), a NCO-terminated condensation product of poly (1,4-oxybutyl-ene)diol and TDI is used, as well as some of the more highly functional isocyanates, such as polymethylenepolyphenyl isocyanate (Papi, Carwin Chemical Co.). 

E I du Pont Nemours Co Elastomer Chemicals Dept, Wilmington Delaware, USA, R M Murray and D C Thompson, The Neoprenes, Formal Reports-Basic Principles of Compounding, Informal reports-Basic Details of Compounding and Test data, Hypalon Reports, Viton Bulletins, Adiprene Bulletins and Extensive reports on various Specialty Rubbers. 

Athey, R.J. "Technical Trade Information on Adiprene Water Resistance of Liquid Urethane Vulcanizates" Wilmington, DE, DuPont (1965) 8. 

Uniroyal Chemicals. "Adiprene L167." Trade literature (1993) 35. 

Adiprene Polyether-based polyurethane (elastomer) Du Pont... 

Adiprene [Du Pont], TM for a polyurethane rubber, the reaction product of diisocyanate and polyalkylene ether glycol. In its raw polymer form, it is a liquid of honey-like color and consistency, which is compounded chemically (to polymerize it further) and converted into products by casting and other techniques. 

Materials. The polyurethane precursor materials were Adiprene L-lOO (Uniroyal, Inc.), a poly(oxytetramethylene glycol) capped with toluene diisocyanate, eq. mol. wt. 1030 1,4-butanediol (BD) and 1,1,1-trimethylolpropane (TMP) and, as catalyst, dibutyltin dilaurate (DBTDL). Acrylic precursors included n-butyl methacrylate (BMA), washed with 10% aq. NaOH to remove inhibitor tetramethylene glycol dimethacrylate (TMGDM) crosslinker and benzoin sec-butyl ether (BBE) as a photosensitizer. These materials were dried appropriately but not otherwise purified. 

The elastic textile fiber Spandex (Du Pont s Lycra) is an excellent example of a successful TPE material (U.S. Patent 2,692,873 issued in 1954, but not commercialized by Du Pont until 1962). Another example is the development of Du Pont s Adiprene PU rubber, which is formed by the reaction of 3 parts of PTMEG (an oligomer of 9—11 tetramethylene ether units) with 4.3 parts of TDI to give an isocyanate-terminated prepolymer that is subsequently treated with 0.3 part of TDI and some water to form an urea-linked end product. 

Adiprene . [Uniroyal Uniroyal Chem. Ltd.] Urethane elastomers for cast films and coatings, footwear, cable jackets, belts, hose, coated fabrics, rolls, molded goods. 

Viton Allas Fluoro- sillcone Kalrez Adiprene Neoprene Hypalon Nordel ... 

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