A review of commercially used chemical foaming agents for thermoplastic foams

Literally hundreds of materials have been proposed and evaluated for use as foaming agents over the past 100 years. Only a relative handful of those materials are used commercially at the present time. An extensive review of physical and chemical foaming agents was written by Henry R. Lasman for the first edition of the Encyclopedia of Polymer Science and Technology published in 1965, and is one of the best historical and technical reviews available on chemical foaming agents (1). This paper will be limited to a review of chemical foaming agents that are currently used to produce thermoplastic foams.