Preferential orientation of crystallites spatially confined in lamellar microdomains of polyethylene-block-[atactic poly(propylene)]

Synchrotron small angle X-ray scattering (SAXS), wide angle X-ray scatterin g (WAXS), and transmission electron microscopy were carried out for an orie nted polyethylene-block-[atactic poly(propylene)] with a molecular weight o f 1.13 x 10(5) and a volume fraction of polyethylene of 0.5. Isothermal cry stallization at 93 degreesC did not destroy the pre-formed microdomain, how ever, with a higher crystallization temperature, the microdomain was more h eavily deformed and more crystalline lamella grew. In WAXS profiles, prefer ential orientation of (020) reflection peak was observed, indicating that t he crystalline lamella grew in parallel with the micro domain interface.