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

It was found that lanthanum complex of cyclodextrin derivative ( Delta *b-CD--MAH--La) was a highly active Delta *b-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 Delta *b-CD--MAH--La was efficient in inducing the crystallization of iPP into Delta *b-modification ( Delta *b-iPP), with K Delta *b value of 0.84, while the content of nucleating agent was 0.8 wt.%. Delta *b-iPP could form extensively in the isothermal crystallization temperature range from 110 ?C to 140 ?C, and the highest amount of Delta *b-crystal content was formed at 130 ?C. Besides, it can be known that the addition of Delta *b-CD--MAH--La can obviously facilitate the overall crystallization process of iPP. Under nonisothermal condition, Delta *b-iPP formed at the suitable cooling rates, ranging from 5 ?C to 10 ?C/min. Furthermore, the nucleation mechanism of Delta *b-CD--MAH--La for iPP was correlated to the special configuration of Delta *b-CD--MAH--La.