Free-radical terpolymerization of n-butyl acrylate/butyl methacrylate/D-limonene

D-Limonene (Lim) is a renewable monoterpene derived from citrus fruit peels. We investigated it for use as part of a more sustainable polymer formulation. The bulk free-radical terpolymerization of n-butyl acrylate (BA)/butyl methacrylate (BMA)/Lim was carried out at 80 degrees C with benzoyl peroxide as the initiator. The terpolymerization was studied at various initial BA/BMA/Lim molar ratios, and the products were characterized for conversion, terpolymer composition, molecular weight, and glass-transition temperature. Lim was observed to undergo a significant degradative chain-transfer reaction, which greatly influenced the polymerization kinetics. The rate of polymerization, final conversion, and polymer molecular weight were all significantly reduced because of the presence of Lim. Nonetheless, polymers with relatively high weight-average molecular weights (20,000-120,000 Da) were produced. The terpolymer composition was well predicted with the reactivity ratios estimated for each of the three copolymer subsystems. (C) 2015 Wiley Periodicals, Inc.