Morphology and Spherulite Growth Rate

Thin films of pure iPP and PB-1 homopolymers and iPP/HOCP, PB-l/HOCP blends, when observed under the optical polarizing microscope during the isothermal 

For pure iPP and PB-1 homopolymers and their respective blends, the spherulite radius increases linearly with time t for all T, investigated. For all samples, the isothermal radial growth rate G was calculated at different as G = dR /dt. Generally, the G values decrease an increase in the values and with increase in the amount of noncrystallizable component in the blend. As shown in Fig. 6.1, where the relative G values of the iPP-based blends are reported for = 125°C, the depression of the G values was more pronounced for the blends prepared with HOCP as the second component. 

Analogously, for a given T, the addition of HOCP to PB-1 causes a depression of the G values, allowing the control of the isothermiticy of the PB-1 crystallization at lower To values. 

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