Comparison of crystallization kinetics of miscible blends of syndiotactic polystyrene with atactic polystyrene or poly(1,4-dimethyl-p-phenylene oxide)

Crystallization kinetics were characterized by using isothermal differentia l scanning calorimetry (DSC) analysis on neat semicrystalline syndiotactic polystyrene (s-PS) and its miscible blends with atactic (amorphous) polysty rene (a-PS) or with poly (1,4-dimethyl-pphenylene oxide) (PPO). The crystal lization behavior of neat s-PS polymer was compared to its miscible blends. The results suggest that the crystal growth in melt-crystallized s-PS is n early of homogeneous nucleation and that the growth pattern of the spheruli tes is 3-D spherical. The s-PS component in its miscible blends was found t o crystallize with similar behavior to that of neat s-PS, but with lower Av rami exponents, suggesting that the nucleation mechanism is likely more het erogeneous with blending.