초록 |
Poly(1,4-cyclohexanedimethylene terephthalate) (PCT) has been widely used as an engineering thermoplastic or a component in blends and copolymers because of its applications such as film, molding and fiber-spinning. Recently, it has been investigated by ours that Poly(1,4-cyclohexanedimethylene 2,6-naphthalate) (PCN) as a new engineering material had characteristics such as high melting temperature (>310℃), rapid crystallization rate and high brittleness. When CN unit was copolymerized with CT unit for the purpose to modify the thermal and brittle properties of PCN, it was found that clear melting and crystallization peaks in DSC thermogram and X-ray diffraction patterns were obviously observed for all copolymer composition, which provides a strong evidence for cocrystallization. Cocrystallization behavior in random copolymers whose component homopolymers are both crystalline is a rare phenomenon. In the present study, a series of poly(1,4-cyclohexanedimethylene terephthalate-co-1,4-cyclohexanedimethylene 2,6-naphthalate) random copolymers were prepared and their cocrystallization behavior was systematically investigated using differential scanning calorimetry, wide angle X-ray diffraction and thermodynamic theory. |