Polyurethane geotextile composite liner with improved water resistance and a process for the production thereof

摘要

A water-resistant polyurethane geotextile composite suitable for use as a liner is made by impregnating a geotextile with a water-resistant polyurethane and allowing the polyurethane impregnated in the geotextile to cure. The water-resistant polyurethane composition is a reaction product of (a) a liquid polyisocyanate having an isocyanate content of at least 10% by weight, (b) an isocyanate-reactive component which includes (1) 20-90% by weight castor oil having a water content of less than 0.5% by weight, and (2) a polyether polyol in which at least 70% by weight of the alkylene oxide is propylene oxide, and (c) a urethane catalyst. Low molecular weight diols and triols and fillers may optionally be included.