Effect of orientation on melting of isotactic polypropylene

摘要

AbstractThe effect of uniaxial orientation on the melting of a commercial grade of isotactic polypropylene has been investigated by thermal analytical techniques. Orientation progressively shifts the onset of and the observed melting point to higher temperatures and increases the peak heights of differential scanning calorimetric (DSC) endotherms. The increase in melting point with orientation is attributed to the increase in configurational entropy of the extended melt into which the polymer crystallites melt.