Kinetics of Straininduced Crystallization of Polymers During Flow.
Abstract
Results from experimental studies of strain-crystallized polyethylenes, prepared in a simple shear couette rheometer, indicate a substantial increase in nucleation rate, a decrease in long period, as well as an increase in melting temperature with increasing shear. The changes appear to have the same thermodynamic origin in the reduction of the amount of melt entropy, Delta S', just prior to crystallization according to a strain-induced crystallization theory by Yeh and Hong. Consequently from the measured nucleation rate one can predict what the decrease in long period or the increase in melting temperature should be for a given strain-crystallized polyethylene. For example, the measured melting temperatures are indeed shown to be comparable to those predicted from nucleation rate measurements.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1982
- Accession Number
- ADA122904
Entities
People
- G. S. Y. Yeh
Organizations
- University of Michigan