화학공학소재연구정보센터
Polymer Engineering and Science, Vol.49, No.9, 1688-1695, 2009
Impact Properties and Microhardness of Double-Gated Glass-Reinforced Polypropylene Injection Moldings
Injection moldings with weld lines were produced in glass reinforced polypropylene grades differing in filler content using a two-gated hot runner injection mold. The skin-core microstructure developed during injection molding was qualitatively analyzed by means of optical and scanning electronic microscopy techniques. The load bearing capacity of the moldings was assessed by uniaxial tensile-impact and biaxial instrumented failing dart impact tests. Microhardness was also used to ascertain the possibility of using it as a simple nondestructive technique for characterizing glass fiber-reinforced injection moldings. The properties were monitored at various points to evaluate their variation at the bulk and the knit region. The biaxial impact test highlights the 10-fold reduction of the impact strength caused by the weld line. POLYM. ENG. SCI., 49:1688-1695, 2009. (C) 2009 Society of Plastics Engineers