Pyrolysis gas chromatographic evaluation of sequence distributions in styrene-ethyl acrylateethyl methacrylate terpolymer.

Abstract

Sequence distributions of styrene(St)-ethyl acrylate (EA)-ethyl methacrylate(EMA) terpolymer were evaluated. Pyrolysis was performed at 590°C using a Curie point pyrolyzer. A parameter P₂(EA-EA)/P₁(EA) ratio, where P₂(EA-EA) was EA-EA diad and P₁(EA) was EA monomer concentration, was applied to evaluate the sequence distribution of EA monomer units. P₂(EA-EA)/P₁(EA) ratio could not be obtained by the correction factors for EA/EMA ratio analysis and the EA monomer/dimer ratio in the pyrolytic products, respectively. But, by three dimensional plots between correction factor, EA monomer/dimer ratio and P₂(EA-EA)/P₁(EA) ratio, P₂(EA-EA)/P₁(EA) ratio could be obtained, and also could be calculated by the multiple regression analysis from the correction factor and EA monomer/dimer ratio. Furthermore, the sequence distributions in St-EA-EMA terpolymers {St/EA/EMA= 20/60/20(mole ratio)} synthesized in other ways were evaluated. Then the P₂(EA-EA)/P₁(EA) ratio varied with EA monomer addition time and the block of EA monomer units in the polymer increased as EA monomer addition time was longer.