Studies of rubber-toughened poly(methyl methacrylate): 1. Preparation and thermal properties of blends of poly(methyl methacrylate) with multiple-layer toughening particles

Abstract

The use of sequential emulsion polymerization to prepare toughening particles which comprise two, three and four radially alternating rubbery and glassy layers is described. The conditions which lead to control of particle size and morphology are discussed. The particles were crosslinked during their formation in order to ensure that they retained their size and morphology during blending with poly(methyl methacrylate) (PMMA). In this way, rubber-toughened (RT) PMMA materials with rubbery phases of predefined particle size and morphology were produced, as confirmed by transmission electron microscopy. The glass transitions of the three types of RTPMMA materials were essentially identical because the matrix PMMA was common to each blend and because the rubbery and glassy phases of each of the types of toughening particle were identical in composition.