Microstructure and properties of polycaprolactone/calcium sulfate particle and whisker composites

Polycaprolactone (PCL)/calcium sulfate (CS) particle and whisker composites were prepared by coprecipitation method and studied by evaluating their microstructure, crystallization, and mechanical properties. Results show that both of the CS whisker and particle dispersed in PCL can reduce the spherulite size of PCL and improve the regularity of the spherulite. The nucleation effect of the CS whisker is stronger than that of the CS particle. Mechanical properties of PCL were obviously improved by both of the particle and whisker addition. The flexural modulus and impact strength of the whisker composites are higher than that of the particle composites, which could be explained by the interfacial debonding mechanism. On the basis of the crystallization and mechanical studies, it is found that the size of spherulites and the concentration of CS particles and whiskers have played an important role in the improvement in mechanical properties of the composite. POLYM. COMPOS. 2012. (c) 2012 Society of Plastics Engineers