In situ optical microscope studies at isotactic polypropylene crystallization induced by shear forces – A review

Abstract

A lot of mechanisms and phenomena associated with the polymers crystallization, are not explained presently. For this reason, new methods of isotactic polypropylene (iPP) crystallization phenomena analysis are still sought. One of them are the investigations with use of Linkam CSS450 shear stage. In this work, a short review of the world literature data prepared with use of Linkam shear stage, has been made. Mentioned equipment can be successfully used in: investigations at iPP crystallization mechanisms, describing crystallization kinetics, observations of iPP crystallization in polymers blends and multi-component systems. Several mechanism of shear induced crystallization, which have not been known so far, have been proposed in analyzed publications. Moreover, the known mathematical models and equations, which describe the iPP crystallization kinetics, have been modified for melts crystalized in shear conditions. The experimental data, obtained with use of Linkam CSS450 have been successfully used in mentioned modifications. Furthermore, a few theories regarding the iPP crystallization in heterogeneous compositions, namely: polymer melts with β-nucleating agents, polymer blends and polymer composites, have been presented in the papers reviewed in this work.