초록
Multi-block copolymers of poly(ethylene terephthalate) (PET) and poly(ethylene glycol) (PEG) were synthesized. Similarly, triblock copolymers of PET and poly(ethylene glycol) methyl ether (MPEG) were synthesized. PEG and MPEG of various molecular weights were used. Obtained block copolymers were made into film, and conditioned at 65% RH at $25^{\circ}C$ after vacuum drying. Water contact angle measurement indicated the enrichment of PET domain on the film surface after vacuum drying, and the enrichment of PEG domain on the film surface after conditioning. The hydrophilicity of the film increased as the molecular weight of PEG block increased. Also, the surface energy increased as the molecular weight of PEG increased, and this increase was mainly due to the increase in the polar component of surface energy. In spite of lower PEG contents, triblock copolymers showed relatively good hydrophilicity.