Method of producing foamed polymer materials

摘要

Reacting carbonyls, such as aldehydes and ketones, with amines produces a ketimine or aldimine and a water byproduct. When the ketimine or aldimine reaction occurs in a polymer composition, the polymer becomes foamed due to the evolution of water. Hence, carbonyl and amine containing compounds may be introduced into a polymeric composition to serve as an in-situ blowing agent. The carbonyl and amine containing compounds may be different polymers which will be combined through a ketimine or aldimine linkage to form a graft co-polymer, they may be small molecular weight additives that are placed in the composition with a polymer that is to be foamed as a byproduct of a ketimine or aldimine reaction of the additives, or they may be a polymer containing a carbonyl or amine moiety and a small molecular weight additive compound that will react with the moiety on the polymer to form a ketimine or aldimine.