| 초록 |
Poly(vinyl alcohol) (PVA) obtained by the saponification of poly(vinyl ester) like poly(vinyl acetate) or poly(vinyl pivalate) is a semicrystalline polymer, which have inter- and intramolecular hydrogen bondings. PVA is classified into three types, such as isotactic, atactic (a-), and syndiotactic (s-) ones according to the stereoregularity of hydroxyl group. In this study, the s-PVA/a-PVA blend films were prepared by casting an aqueous solution of a-PVA/s-PVA of 100/0, 99/1, 95/5 and 90/10 (wt%), respectively. And, to determine the miscibility of the blends, the melting temperature variations with blend compositions were measured by differential scanning calorimetry. As the s-PVA ratio was increased, melting temperature of blend film was increased due to an increasement of intermolecular hydrogen bonding of PVA chains. In addition, the behaviors of crystallization and melting of blends were investigated in terms of syndiotacticity. |
