摘要 |
Low density foams are prepared from an admixture which comprises a medium which is polymerizable and/or crosslinkable by free radical initiation, a t-alkylhydrazinium salt blowing agent, a peroxide curing agent, a suitable surfactant, and at least one transition metal salt promoter wherein at least one of the metal salts is a compound of iron or copper. The t-alkylhydrazinium salt blowing agent in the presence of an effective amount of the transitional metal salt promoter improves the efficiency of the process. |