MODELING INTERFACIAL STRENGTH OF POLYBUTYLENE SUCCINATE(PBS)/POLYPROPYLENE(PP) MULTILAYER INJECTION-MOLDED PART USING FINITE ELEMENT METHODS

摘要

Polypropylene (PP)-based sandwich injection moldings containing biodegradable polymers in the core were carried out. Interfacial adhesion between the skin and the core is essential for obtaining sufficient mechanical strength for commercial applications. In order to investigate the interfacial strength between the skin and the core, the ASTM/ISO scratch test was used and critical delamination load for delamination was determined. For comparison, an 180° peel test was also conducted, whereby the skin was peeled off from the core, to measure its adhesive force in a different way. Numerical simulation using FEM was applied to these experiments to study interfacial strength. Destruction of the interfacial layer was defined by either a critical stress or critical strain criterion. The critical strain criterion appears to better describe the phenomenon in these two experiments. FEM simulation could qualitatively correlate with these behaviors, suggesting that delamination could be described as a strain dominant phenomenon.