Comparative study of the nucleation activity of third-generation sorbitol-based nucleating agents for isotactic polypropylene

Autor: J. M. Arribas, Gary Ellis, Marián A. Gómez, Carlos Marco
Rok vydání: 2002
Předmět:
Zdroj: Journal of Applied Polymer Science. 84:2440-2450
ISSN: 0021-8995
Popis: The nucleation activity of the sorbitol derivatives 1,2,3,4-bis(3,4-dimethylbenzylidene sorbitol) and methyldibenzylidene sorbitol are compared with that of talc, a conventional nucleating agent for the monoclinic crystalline phase of isotactic polypropylene. The thermal parameters associated with the dynamic crystallization process are studied as a function of the cooling rate by differential scanning calorimetry, and the nucleating efficiency is assessed by comparison with self-nucleation, the highest values being observed for 1,2,3,4-bis(3,4-dimethylbenzylidene sorbitol) over the whole concentration range. The nature of the polymer crystals formed in the nucleated polymer was studied by X-ray diffraction, and the data show an increase in a preferred orientation of the polymer crystallites with increasing concentration of nucleating agent. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2440–2450, 2002
Databáze: OpenAIRE