Microcellular plastics technology

Microcellular plastics (MCPs), which were first invented at the Massachusetts Institute of Technology in 1979, refer to any polymeric materials that have closed cells of very small diameters, typically smaller than 50 /rm. The cell density can be made to vary a great deal depending on the final application of a given MCP. MCPs can have as many as 10 bubbles/cm when the bubble diameter is 0.1 /rm, 10 bubbles/cm for 1-p.- and 10 for 10-/r- diameter cells. They can be created in thermoplastics, thermosetting plastics, and elastomers. Figure 1 shows the microstructin-e of a typical MCP. See Reference 1 for a detailed historical account as well as a detailed review of MCPs. 

Shimbo M. Foam Injection Technology and Influence Factors of Microcellular Plastics , FOAMS 2000, 162 (2000). 

The concept of microcellular thermoplastic foam was developed in the 1980s by researchers at the Massachusetts Institute of Technology and was based on the idea that the creation of a very large number of microbubbles, smaller than the preexisting natural flaws in a polymer, can reduce the material cost and consumption in mass produced plastic parts without compromising mechanical properties [15, 16]. 

The short-term objectives of the proposed research includes the design and development of a extrusion-assisted rotational foam molding experimental setup that will be utilized to facilitate the understanding of the process and the experimental work intended to determine the feasibility of successfully developing an extrusion-assisted plastic foam fabrication technology for lightweight integral-skin fine-celled as well as microcellular rotationally molded foams. 

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