Compatibility and crystallization studies on poly(phenyl acetylene) polycaprolactone blend

The compatibility and crystallization behavior of poly(phenyl acetylene) (P PA)/polycaprolactone (PCL) blends were investigated. PPA and PCL were parti ally miscible in the melt. PCL composition in the PCL-rich phase was calcul ated from the observed glass transition temperature with the consideration of the perturbation of amorphous phase composition by the crystallization o f PCL. PCL composition in PCL-rich phase ranged from ca. 91 wt% to 94 wt%. The melting point of PCL was depressed upon blending. The isothermal crysta llization kinetics of the blends was analyzed by Avrami equation. The cryst allization rate decreased with increasing PPA composition in the PCL-rich p hase. The crystal fold surface free energy sigma(e) of ca. 90 erg cm(-2) wa s obtained from Lauritzen Hoffman analysis considering regime II kinetics. Fold surface free energy was found to increase slightly with PPA compositio n.