Microstructure of copolymers obtained from chemical modification of phenoxy resin: a C-13 NMR Study

The microstructure of a series of copolymers obtained from the chemical mod ification of poly(hydroxy ether of bisphenol-A) (phenoxy resin) with differ ent degrees of modification has been investigated by H-1 and C-13 NMR spect roscopy. In the C-13 spectra, the resonance due to all quaternary carbons o f bisphenol-A unit appear to be sensitive to the compositional sequence dis tribution of the copolymer and exhibit clear diad splitting. The experiment ally determined average sequence length is found to be in accord with ideal random distribution statistics with randomness close to unity. These resul ts could be useful in the study of the microstructure of other phenoxy modi fications, in polymer blends based on phenoxy and epoxy resins where trans reactions can occur. They could also be useful in the determination of the branching microstructure of bisphenol-A based epoxy resins. (C) 2000 Societ y of Chemical Industry.