Shear induced crystallization in poly(ε-caprolactone): effect of shear rate

✍ Scribed by D. Lellinger; G. Floudas; I. Alig

• Book ID: 104163919
• Publisher: Elsevier Science
• Year: 2003
• Tongue: English
• Weight: 461 KB
• Volume: 44
• Category: Article
• ISSN: 0032-3861
• DOI: 10.1016/s0032-3861(03)00633-5

✦ Synopsis

We have studied the effect of shear rate on the very early stages of poly(1-caprolactone) crystallization with in situ rheology and ex situ optical microscopy. The effect of shear rate is mainly to increase the nucleation density and to speed-up the crystallization process. Thermally-induced crystallization is separated from strain-induced crystallization allowing the construction of a 'master curve' indicating that the system obeys the shear rate-temperature-superposition. It was found that the free enthalpy difference in the melt G m ð _ g; TÞ 2 G m ð _ g ¼ 0; TÞ increases with the shear rate ð _ gÞ that can be qualitatively rationalized by the reduced entropy of the melt prior to crystallization.