FLEXIBLE AUTOMOBILE EXTERIOR BODY PARTS PRODUCED FROM POLY-(OXYPROPYLENE)GLYCOL BASED POLYURETHANE ELASTOMER

摘要

1513462 Polyurethane elastomers UNIROYAL Inc 10 May 1975 [10 May 1974] 14814/75 Heading C3R A polyurethane elastomer comprises a reaction product of (1) a prepolymer formed by the reaction of a polymeric diol selected from poly- (oxypropylene) glycol and poly(oxypropylene)- glycol tipped with 10% wt. of ethylene oxide and having a molecular weight of from 1750 to 2500 and methylenebis(4-phenyl isocyanate), and (2) 1,4-butane diol, the molar ratio of 1,4- butane diol to the polymeric diol ranging from 3-0 : 1 for a 1750 molecular weight polymeric diol to 9À0 : 1 for a 2500 molecular weight polymeric diol, the NCO/OH equivalents ratio being from 0À95 to 1À20. The elastomer preferably has a hardness of 40 to 55 Shore D, an elongation of greater than 300%, an ultimate tensile strength of at least 3000 p.s.i. and a Die C tear strength of at least 500 p.l.i. Uses.-Moulded automobile flexible body parts.