Polyurethane Catalyst PC-77: A Secret Weapon to Improve the Quality of High-Performance Polyurethane Foam Introduction: A revolution about “bubble” In the vast starry sky of modern industry, polyurethane (PU) is undoubtedly a dazzling star. From car seats to sports soles, from refrigerator insulation to building insulation, polyurethane is everywhere. Behind this “bubble” miracle, there is...