news Optimizing Polyurethane Catalyst PC-77 in Flexible Foam Sealing Materials for Automotive Gaskets Optimizing Polyurethane Catalyst PC-77 in Flexible Foam Sealing Materials for Automotive Gaskets Ⅰ. ... 04/0713Optimizing Polyurethane Catalyst PC-77 in Flexible Foam Sealing Materials for Automotive Gaskets