THERMAL-PROPERTIES OF ETHYL ALPHA-HYDROXYMETHYLACRYLATE-METHYL METHACRYLATE COPOLYMERS

The degradation and glass transition temperatures of a series of methy l methacrylate (MMA)-ethyl alpha-hydroxymethylacrylate (EHMA) copolyme rs have been studied by t.g.a./i.r. and d.s.c. Thermal degradation yie lded intramolecular lactone and intermolecular crosslinking formation, with concurrent loss of ethanol and/or methanol involving adjacent or near-neighbour EHMA or MMA units. Glass transitions of copolymers hav e been analysed as a function of sequence distribution and their value s compared to the theoretical ones derived using Johnston's equation. The partially degraded copolymers increased their glass transition tem peratures as a consequence of the above mentioned lactone and crosslin king formation.