Effects of Strains on Rheological Properties in the Course of Isothermal Crystallization of Polybutene-1
Hisahiko KASHIHARA, Masaoki TAKAHASHI, Kenji URAYAMA and Toshikazu TAKIGAWA
Abstract:Effects of strains on rheological properties in the course of isothermal crystallization of polybutene-1 have been investigated. Dynamic viscoelasticity measurements made as a preliminary experiment showed that an induction period emerged on the plots of dynamic storage and loss moduli against time. The induction period was affected by the strain amplitude (ƒÁ) in the region of ƒÁ > 0.03, but was independent of ƒÁ at ƒÁ _< 0.03. The induction time for the dynamic measurement was independent from the frequency, but that for the steady shear measurement depended on the shear rate: the larger the shear rate, the shorter the induction time. This induction period was not governed by the total strain. Key Words:Isothermal crystallization, Steady flow, Rheology, Polybutene-1