The Influence of Injection-Molding Variables and Nucleating Additives on Thermal and Mechanical Properties of Short Glass Fiber/PET Composites

Abstract

Investigation of thermal and mechanical characteristics of short glass fiber reinforced polyethylene terephthalate (PET) has been carried out, focusing on the influence of three of the variables involved in the injection-molding process: mold temperature, holding pressure time and closed mold time. Mold temperature plays a decisive role in controlling crystallinity development of PET matrix, which is directly correlated with the values of tensile strength and elongation at rupture. Holding pressure time acts improving piece compaction. Longer closed mold times lead to the highest values of developed crystallinity. Moreover, sodium benzoate, titanium dioxide and an ionomer have been added in order to study efficacy as nucleating agents.