| 초록 |
Gas pressure effect on the phase transitions of various block copolymers was studied by birefringence. For this purpose, a special pressure cell that allows us to have pressure range between 0~ 150 bar and temperature range between room temperature to 300 oC, was designed. For deuterated polystyrene-block-poly(n-pentyl methacrylate) copolymer (dPS-b-PnPMA), two transitions (the lower disordered-to-ordered transition (LDOT) and the upper ordered-to-disordered transition (UODT)) consisting of the closed-loop were obtained at various nitrogen gas pressures. It was found that the size of the closed-loop became larger with increasing nitrogen gas pressures. Other gas such as helium and argon was also used to compare the phase behavior with nitrogen. |
