✦ LIBER ✦

Crystallization regimes and reptation in polypropylene molecular weight fractions

✍ Scribed by A. O. Ibhadon

Publisher: John Wiley and Sons
Year: 1999
Tongue: English
Weight: 114 KB
Volume: 71
Category: Article
ISSN: 0021-8995
DOI: 10.1002/(sici)1097-4628(19990124)71:4<579::aid-app9>3.0.co;2-6

No coin nor oath required. For personal study only.

✦ Synopsis

Crystal growth rate data based on the kinetic nucleation theory of chain folding and the effect of reptation, have been used to predict the rate of crystal growth at moderate to high supercoolings in iPP molecular weight fractions. Growth rate data obtained for the fractions seem to be in agreement with the theoretical predictions of the regime theory. However, an extension of the gambler ruin treatment to the iPP data has not been successful with regard to the dominant morphology in regime II. The variable cluster model suggested as the morphology for polyethylene in regime II does not appear to be evident from this study. The effect of polydispersity, molecular weight, and tacticity on the crystallization behavior of iPP fractions have also been studied and correlated with the structure of polymer samples investigated.

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