Toughened phenolic foam

摘要

Disclosed is a phenolic closed-cell foam including polyvinyl pyrrolidone (PVP) as a toughening agent. Also disclosed is a resin mixture for forming a phenolic closed cell foam, the resin mixture comprising PVP as a toughening agent. The PVP has a molecular weight of from 5,000 to 80,000 and is present in the mixture (excluding blowing agent) in an amount of from 4% to 20% by weight. The foam cells are substantially free of holes or surface defects. The foam has superior fire performance.