| abstract |
A blowing agent blend for making thermoplastic polymer foams comprises methyl formate. The blowing agent blend can further comprise at least one co-blowing agent, preferably an environmentally friendly chemical species (e.g., non-VOC and/or non-HAP). The co-blowing agent is either a physical co-blowing agent (e.g. an inorganic agent, a hydrocarbon, a halogenated hydrocarbon, a hydrocarbon with polar, functional group(s), water or any combination thereof), or a chemical co-blowing agent, or combinations thereof. The blowing agent blend can comprise any combination of methyl formate and one or more co-blowing agents, wherein the preferred co-blowing agent is 1-chloro-1, 1-difluroethane (HCFC-142b). The thermoplastic polymer foam can be an alkenyl aromatic polymer foam, e.g. a polystyrene foam. The methyl formate-based blowing agent blends produce stable foams for various applications, including containers, packaging systems, as well as insulation boards and building materials. A process for the preparation of such foams is also provided. |