Patent ID: 6914117
Filing Date: 2005-07-05
Classification: C08G

Abstract:
1. A process for preparing an elastomeric polyurethane material having a shore A hardness of at most 5 (DIN 53505), a density of 500 kg/m 3 or more (DIN 53420), a compression load deflation at 40% (CLD) of 600 kPa or less (DIN 53577), and a resilience of 25% or less (ISO 8307) comprising the step of reacting: 1) a polymethylene polyphenylene polyisocyanate having an average isocyanate functionality of 2.4 or more, 2) a polymeric polyol having an average equivalent weight of at least 500 and an average nominal hydroxyl functionality of 2-4, 3) a polymer having a nominal hydroxyl functionality of 1 and an average equivalent weight of at least 500, and 4) optional additives and auxiliaries known per se in an amount of less than 5% by weight (based on the weight of the polyisocyanate, polymeric polyol 2) and polymer 3)), wherein the reaction is conducted at an index of 90-110 and the equivalent amount of polymer 3) is 25-80% of the available NCO equivalents.