Abstract
Making use of infra-red spectra and ’H NMR spectra, we characterized the molecular structure of polytrimethylene terephthalate (PTT) which was synthesized by ourselves, and compared the resulting PTT with polybutylene terephthalate (PBT) and polyethylene terephthalate (PET). The crystallization kinetics for PTT was compared with those for PBT and PET. The crystallization activation energies of these three polyesters were weakened in the order of PET>PTT>PBT. It seems that the difference in the flexibility of molecular chains influences the crystallization activation energies.