Polystyrenes injection molding parameters

The method of incomplete mold filling is effective for investigating injection molding of fiber glass-loaded polypropylene and polystyrene melts.283 After solidification, samples were prepared for microscopic investigation. The authors determined the distribution and orientation of the fibers in different sections of the article and thus were able to clarify the pattern of flow in different parts of the mold as a function of the process parameters. They concluded that the width of the (cavity)... 

S. R. Tremblay, P. G. Lafleur and A. Ait-Kadi, Effects of injection parameters on fiber attrition and mechanical properties of polystyrene molded parts. Journal of Injection Molding Technology, 4, 1-7 (2000). 

Various parameters are evaluated which may affect ejection force during injection molding of syndiotactic polystyrene. Increase in mold temperature results in large decrease of ejection force. A predictive model was developed which allows evaluation of the combination of hold pressure, melt temperature, and mold temperature. To decrease ejection force by 72%, mold temperature has to be increased from 60 to 93°C. Also, increase of hold pressure contributes to a small decrease of ejection force. Figure 10.11 shows the effect of mold temperature and temperature of the part, immediately after ejection on the ejection force. 

EFFECTS OF PROCESSING PARAMETERS ON OPTICAL PROPERTIES OF INJECTION MOLDED POLYSTYRENE PARTS... 

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