Poly spherulite growth kinetics

Regime transition is presented when the data are analyzed with the Lauritzen and Hoffman kinetic theory. Di Lorenzo demonstrated that the discontinuity in the spherulite growth rate is not associated to any change in superstructural morphology. Tsuji et al. and Yuryev et al. also observed this unusual bimodal crystallization behaviour for pure PLLA, while the normal characteristic bell-shaped spherulite growth rate dependence was seen for poly(L/D-lactide) copolymers. 

In order to evaluate the application of modulated-temperature differential scanning calorimetry (M-TDSC) to the study of the crystallisation kinetics of semicrystalline polymers, isothermal crystallisation kinetics in poly(e-caprolactone)-SAN blends are investigated. The temperature dependence of d In G/dT (G =crystal growth rate), determined by M-TDSC agrees approximately with previous experimental data and theoretical values. These were obtained from direct measurements of spherulite growth rate by optical microscopy. Here, theoretical and M-TDSC experimental results show that the d In G/dT versus temperature plots are not sensitive to the noncrystalline component in the poly(e-caprolactone)-SAN blends. 15 refs. 

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