Glass transition induced by solvent desorption for statistical MMA/nBMA copolymers - Influence of copolymer composition

An experimental study of the glass transition induced by solvent desorption has been performed for a series of Methyl methacrylate (MMA)ln-butyl metha crylate (nBMA) statistical copolymer films. The glass transition temperatur e of the dry homopolymers, PMMA and PnBMA, are, respectively, about 105 and 7 degreesC above the temperature of the experiment, so that the glass tran sition domain can be analyzed in detail by varying the solvent concentratio n and the copolymer composition. A strong coupling was found between drying dynamic and stress relaxation. In particular, the quantitative analysis of the desorption isotherms based on the Leibler-Sekimoto approach led to a b ulk modulus K that increases as the proportion of nBMA increases, contrary to the behavior of dry annealed samples. (C) 2000 Elsevier Science Ltd. All rights reserved.