Polarized optical microscopy showed that the texture of spherulites became rougher on increasing the PVAc content. In the case of P(VAc-co-VA) copolymer, the intensity of polarized light decreased significantly,indicating that P(VAc-co-VA) component seemed to be expelled out of the interfibrillar regions. Scanning electron microscopy analysis revealed that the significant phase separation occurred with increasing the degree of hydrolysis. In the case of 70/30 blend of PLA and
P(VAc-co-VA) with 30 mol% vinyl alcohol, the P(VAc-co-VA) copolymer formed the regular domains with a size of about 10 mm.