ONE-SHOT POLYURETHANE ELASTOMERS WITH VERY LOW COMPRESSION SETS

摘要

The present invention relates to a process for the production of one- shot polyurethane elastomers having low compression sets. This process comprises reacting a polymethylene poly(phenylisocyanate) having an average functionality of 2.2 to 2.8, and a polyol component that has an average functionality of 2.0 or less. The polyol component comprises at least one relatively high molecular weight isocyanate-reactive component, and at least one relatively low molecular weight isocyanate-reactive component, with the functionalities and quantities of each component being such that the above average functionality of 2.0 or less for the polyo l component is satisfied. Polyurethane elastomers produced by the process of this invention are characterized by compression sets of less than 10%.