Mechanical properties and crystallization behavior of polypropylene with cyclodextrin derivative as β-nucleating agent

Abstract

It was found that lanthanum complex of cyclodextrin derivative (β-CD–MAH–La) was a highly active β-nucleating agent for isotactic polypropylene (iPP) in this study. The influence of the nucleating agent on mechanical properties and isothermal and nonisothermal crystallization behavior of iPP has been investigated. Results showed that β-CD–MAH–La was efficient in inducing the crystallization of iPP into β-modification (β-iPP), with K β value of 0.84, while the content of nucleating agent was 0.8 wt.%. β-iPP could form extensively in the isothermal crystallization temperature range from 110 °C to 140 °C, and the highest amount of β-crystal content was formed at 130 °C. Besides, it can be known that the addition of β-CD–MAH–La can obviously facilitate the overall crystallization process of iPP. Under nonisothermal condition, β-iPP formed at the suitable cooling rates, ranging from 5 °C to 10 °C/min. Furthermore, the nucleation mechanism of β-CD–MAH–La for iPP was correlated to the special configuration of β-CD–MAH–La.