Extrusion processing for manufacture of low-density microcellular polycarbonate foams uing carbon dioxide.
Published: 2004
Language: eng
Number of pages: 97
Description: This thesis presents the effective strategies for increasing the volume expansion ratio and the cell density of polycarbonate foams. The basic strategies are: (a) to use sufficiently high pressure all through the extrusion system; (b) to use branched material; (c) to use high pressure drop rate at the die exit; (d) to use sufficiently high contents of CO 2; (e) to optimize the processing temperature. The effects of processing and material parameters on foam morphologies were thoroughly studied using a single-screw tandem foam extrusion system. By tailoring the processing and material parameters, polycarbonate foams with an expansion ratio of up to 19 times with a cell density over 1010 cells/cm3 were successfully produced.A continuous extrusion process for the manufacture of low-density microcellular polycarbonate (PC) foams using CO2 is presented. Due to its outstanding mechanical properties and high thermal resistance, polycarbonate foams have been considered as a candidate that will broaden the applications of foams in new industrial areas with high temperature environments.
Notes: Adviser:  Chul B. Park.

Thesis (M.A.Sc.)--University of Toronto, 2004.

Electronic version licensed for access by U. of T. users.

Source: Masters Abstracts International, Volume: 43-03, page: 0960.

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