Foam injection molding processes
Lightweight polymers produced in injection molding

Injection-foaming processes for producing microcellular polymeric materials have been extensively studied over the past thirty years . The microcellular structure is formed by the nucleation, growth, and sometimes coalescence of bubbles within the polymer matrix. Gas is introduced into the polymer matrix through either a chemical or physical process. In the physical method, inert gases, such as carbon dioxide (CO₂) or nitrogen (N₂), are introduced directly into the polymer. In the chemical method, the gas is produced by the decomposition reaction of chemical blowing agents that are mixed with the...