Thermodynamics of Solubilization of Functional Copolymers in the Grafted Shell ofCore-Shell Impact Modifiers: 2. Experimental

摘要

Certain styrene/maleic anhydride copolymers (SMA) are completely miscible withpoly(methyl methacrylate) (PMMA). This paper explores the solubilization of SMA copolymers in the grafted PMMA shell layer of emulsion-made core-shell impact modifiers by examining glass transition behaviour and morphology of SMA/core-shell modifier blends. There appears to be a single, composition-dependent hard phase Tg for these blends at all compositions by dynamic mechanical analysis. Transmission electron microscopy reveals that SMA copolymers are evenly distributed around the core shell particles. Neither approach was able to determine the upper solubilization limit expected from theoretical considerations. A blend of core-shell modifier with polystyrene (PS), which is not miscible with PMMA, was also examined for comparison.