PHASE-STRUCTURE OF ETHYLENE DIMETHYLAMINOETHYL METHACRYLATE COPOLYMERS AND ITS RELATION TO COMONOMER CONTENT AS STUDIED BY SOLID-STATE HIGH-RESOLUTION C-13 NMR-SPECTROSCOPY

The phase structures of a series of ethylene-dimethylaminoethyl methac rylate (EDAM) copolymer samples were investigated by solid-state high- resolution C-13 n.m.r. spectroscopy. It is found that at least the alp ha and beta methylene units relative to the tertiary carbon of dimethy laminoethyl methacrylate (DAM) along the molecular chain as well as DA M comonomer units are located outside the crystalline region. The C-13 CP-MAS spectra also reveal that with increasing DAM content, the rati o of monoclinic to orthorhombic crystals increases as well as the rati o of interfacial to crystalline regions. (C) 1997 Elsevier Science Ltd .