Naphthyl Copolyester with High Glass Transition Temperatures: Tunable Structure and Performance

A series of poly(ethylene bis[4-(2-hydroxyethoxy)phenyl]sulfone 1,4-cyclohexanedimethylene 2,6-naphthalate) (PESCNs) copolyesters from amorphous to crystalline were prepared by melt polymerization. The chemical structure and compositions were explored by hydrogen and carbon nuclear magnetic spectroscopy (1H NMR and 13C NMR). The glass transition temperature (Tg) of copolyesters (128.1–134.5 °C) was higher than that of PEN (about 120 °C) and showed tunable characteristics with the composition of polymerization. With the incorporation of CHDM, the thermal stability of the copolyesters decreased slightly while the fluidity improved, owing to the easier conformational transition ability of CHDM. An interesting transition from brittleness to toughness was also achieved via regulating CHDM content. In addition, all the prepared copolyesters exhibited good transmittance (∼85%) under both UV and C light sources. In view of these unusual performances, PESCNs exbibit potential for use in the fields of electronic devices, fibers, and cosmetic packaging.