Journal of Applied Polymer Science, Vol.106, No.4, 2718-2723, 2007
Crystallization behavior of dry-brush PEO-PS block copolymer and PEO homopolymer blend
The crystallization behavior of semicrystalline PEO homopolymer/triblock PS-PEO-PS copolymer blend system, which exhibited "Dry-Brush" in the melt. A symmetric polystyrene-poly(ethylene oxide)-polystyrene triblock copolymer was blended with PEO hornopolymer (h-PEO) having the same molecular weight as that of the PEO block in the copolymer. Considering the composition of the blend (W-ps >= 0.8), PEO spheres were formed in the blend. Because of the dry-brush phase behavior of this blend, h-PEO added was localized in the PEO microdomains, which increases the domain size without changing the microdomain morphology. The crystallization of PEO block was confined within the microdomains and the crystallization temperature was about 60 degrees C lower than normal. Self-seeding tests were performed to clarify the nucleation mechanism of the blend. Because the droplets size varies greatly, multicrystallization peaks were witnessed in the self-seeding process. (c) 2007 Wiley Periodicals, Inc.