Microcellular Foam Injection Molding of Thermoplastics Using Green Physical Blowing Agent

Abstract:

The microcellular injection molding technology, commercially offered by Trexel Inc. and other manufacturers, is primarily a close cell foaming technique. This process is capable of offering light weight non-porous thermoplastics moldings. The foaming of thermoplastics with open cellular morphology has got various high end applications among others like tissue engineering and membrane separation. Some of the researchers were successful in synthesis of open cellular thermoplastics at laboratory scale via solid state batch process. The growing demand for microporous thermoplastics, especially the biodegradable plastics (e.g. Polylactic acid), motivated the researchers develop a specialized microcellular injection molding process for processing of open cell thermoplastics using physical blowing agents such as supercritical nitrogen or carbon dioxide gas. A brief of theoretical and conceptual treatment of microcellular injection molding is presented.

• Periodical: Materials Science Forum (Volume 875)
• Pages: 77-111
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.875.77
• Online since: October 2016
• Authors: S.J.A. Rizvi*
• Keywords: Microcellular Foam, Microcellular Injection Molding, Nucleation, Open Cell Foam, Physical Blowing Agent, Supercritical Fluid

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