High Performance Polyurethane Elastomers. Part 2. Millable Elastomers and Syntactic Foams
EXPLOSIVES RESEARCH AND DEVELOPMENT ESTABLISHMENT WALTHAM ABBEY (UNITED KINGDOM)
Pagination or Media Count:
Polyurethane elastomers based on millable sulphur cured polycaprolactone, polyoxy 1,4- butylene glycol and hydroxyl terminated polybutadienedi-isocyanate precursors, chain extended with unsaturated diols, together with liquid cast polyoxy 1,4- butylene glycol di-isocyanate prepolymers filled with small hollow spheres syntactic foams were assessed to determine their resistance to water 80 C and Standard Test Fluid 65 C. Two commercially supplied urethane elastomers, one based on a low molecular weight polyether toluene di- isocyanate prepolymer cured with methylene- bis-2-chloroaniline, the other on a higher molecular weight polyether4,4-methylene bis-cyclohexyl di-isocyanate prepolymer, cured with methylene bis-aniline were also assessed for comparison. A millable caprolactone urethane elastomer gave fair resistance to standard test fluid at 65 C COUPLED WITH A VERY LOW PERMEABILITY TO STANDARD TEST FLUID AT 30 C, while a millable polyether urethane elastomer gave good resistance to water at 80 C. A low density buoyant polyether based syntactic foam, filled either with hollow glass or fly-ash spheres, gave good resistance to water at 80 C.
- Elastomers and Rubber