COMPARISON OF ELECTRON AND INFRARED-SPECTROSCOPY WITH THERMAL-ANALYSIS TO STUDY MOLECULAR-WEIGHT EFFECTS IN PVC-PMMA BLENDS

The effects of homopolymer molecular weight on the miscibility of PVC/ PMMA solvent cast blends were studied. Two significantly different mol ecular weights were chosen for each of the homopolymers, and a series of blends was prepared from the four possible homopolymer-homopolymer combinations. Angle-dependent ESCA results suggest that the surfaces o f the blends are enriched with PMMA. The extent of this enrichment is dependent on molecular weight, with the most enrichment seen in blends containing the lower-molecular-weight PMMA homopolymer. Differential scanning calorimetry (DSC) results are also presented.