Mold Shrinkage of Colored Plastics Induced by Organic Pigments

摘要

Mold shrinkage of the colored plastics based on polyethylene and polypropylene is a well-known phenomenon and is considered due to pigment-induced crystallization of polymers. A systematic investigation has been carried out for the clarification of a correlation between crystalline nucleation effect by organic pigments and mold shrinkage in polypropylene systems in terms of measurement of crystallization rates and microscopic observation of the crystalline state.