| The issue of faster cooling time has been of great concern for the manufacturers of exothermic and endothermic blowing agents. This study explores the truth regarding this difference for structural foam molding.; In this study, four blowing agents (two endothermic and two exothermic) were used to foam polypropylene, using the low-pressure molding technique. In order to do a fair study, the molding conditions were standardized. Besides observing the molding time, the flexural and instrumented impact properties were tested to observe the performance of an individual blowing agent in relation to the others.; It was observed that endothermic blowing agents produced faster molding times than exothermic blowing agents. When the density was reduced the cycles became faster. The position along the plaque from where the sample was tested affected the flexural properties. |
