Polymer Engineering and Science: Novel foam injection molding technology using carbon dioxide-laden pellets

摘要: Injection moulding of foamed components typically uses chemical blowing agents (CBAs) or physical blowing agents (PBAs) to produce a cellular or microcellular structure. A CBA can be easily and directly mixed with plastic pellets and fed into the moulding machine through the hopper while a generally finer, microcellular structure can be realized using PBAs. The PBA route is accomplished by injecting more environmentally benign gases into the machine barrel to form a single-phase polymer-gas solution that subsequently foams during moulding. This article proposes a new foam injection moulding technology that enables the ease of processing of the CBA method with the foaming characteristics of a PBA, but in a cost-effective fashion. In this article, the manufacturing method and theoretical background for producing plastic pellets loaded with carbon dioxide as well as the resulting part characteristics are …