Process optimization of thermoforming PP/CaCO3 composites

Thermoforming of polypropylene/CaCO3 composite sheets has become an importa nt process in industry because of their low cost and good formability. Howe ver there are some unsolved problems that confound the overall success of t his technique. Nonuniform thickness distribution caused by inappropriate mo ld design and processing condition is one of them. An L'18 experimental mat rix design based on the Taguchi method was conducted to optimize the thermo forming process of CaCO3 filled polypropylene composites. For the factors s elected in the main experiment, the assist plug's displacement and velocity were found to be the principal factors affecting the thickness distributio n of thermoformed composites.