COMPOSITIONAL HETEROGENEITY OF ETHYLENE T EREPHTHALATE-ETHYLENE OXIDESEGMENTED COPOLYMER WITH LONG SOFT SEGMENT

The series of ethylene terephthalate-ethylene oxide segmented copolyme rs with different long soft segments and different hard segment conten ts have been synthesized, The hard segment contents are measured by H- 1 NMR, Four PET-PEG segmented copolymers were separated into soluble a nd insoluble parts in chloroform, The results have revealed a very evi dent compositional heterogeneity in these four samples, which depends on the molecular weight of soft segment and hard segment content, Simu ltaneously the melting and thermal spectra of the four PET-PEG segment ed copolymers were obtained by DSC, The soluble and insoluble parts ha ve shown the quite different crystallizability both for soft and hard segments, which has the good correspondence with the compositional het erogeneity.