Modifying the properties of poly(1,4-cyclohexylenedimethylene terephthalate) by hydroquinone bis(2-hydroxyethyl) ether

A new copolyesters of poly(2-[4-(2-hydroxyethoxy)phenoxy]ethyl-co-1,4-cyclohexylenedimethylene terephthalate) (PHCT) with different compositions were synthesized from terephthalic acid, 1,4-cyclohexanedimethanol and hydroquinone bis(2-hydroxyethyl) ether (HQEE) via esterification-polycondensation reaction. The synthesized copolyesters were analyzed by H-1-NMR, FT-IR, GPC, intrinsic viscosity, DSC, TGA and tensile testing, respectively. The H-1-NMR and FT-IR analysis confirm the successful introduction of HQEE into poly(1,4-cyclohexylenedimethylene terephthalate (PCT) chains. The introduction of HQEE into PCT chains can effectively lower the melting point of PCT, making it easier to process. The glass transition temperature of PHCT is higher than 70 celcius and it has the comparable thermal stabilities to PCT. In addition, introducing HQEE into PCT chains can effectively improve the molecular weights of PCT, thus imparting PHCT with better mechanical performance relative to PCT. The PHCT is a tough polymer, which owns the higher Young's modulus (above 300 MPa), the higher tensile strength (above 39 MPa) and the higher elongation at break (above 226%).