CORRELATION OF THE THERMAL ANALYSIS OF CHEMICAL BLOWING AGENTS WITH THE CELL MORPHOLOGY OF EXTRUDED, EXPANDED POLYPROPYLENE ROD SAMPLES

摘要

This paper relates the thermal decomposition behaviour of chemical blowing agents (CBAs) with the cell morphology of EPP (expanded polypropylene) produced using those blowing agents. Correlation between decomposition temperatures and rates of the various agents and the cell morphology of extruded, EPP are reported and discussed. The research has revealed relationships between the structure of an extruded PP foam and the thermal decomposition response of the chemical blowing agent used during production. The CBAs tested showed a very wide range of cellular structures under the same processing conditions. Those with a higher temperature and rate of gas evolution generally produced foams with the smallest cell sizes and highest cell densities.