Method for the preparation of rigid foams having urethane and/or isocyanurate groups and being extensively open celled

摘要: A method is described for the preparation of rigid foams, having urethane and/or isocyanurate groups and being extensively open celled, by reacting polyisocyanates with compounds at least two capable isocyanates equivalent weight per reactive group which about 9 to 800, in presence catalysts, surface active substances, as well as, optionally, physical blowing agents, flame retardants other known auxiliary materials finishing wherein reaction carried out liquid, higher molecular weight, unsaturated hydrocarbons, are free isocyanates, amounts 0.01 3.0% based on formulation. Particularly preferred hydrocarbons polybutadiene polyoctenylene an average 800 10,000 g/mole. The because their cell nature, exhibit high dimensional stability.