Determination of reactivity ratios and kinetics of free radical copolymerization of linalool with styrene

Copolymerization of acyclic monoterpenoid, namely linalool (LIN), with styrene (STY) initiated by benzoyl peroxide (BPO) p-acetyl benzylidene triphenyl arsonium ylide (p-ABTAY) in xylene separately at 80degreesC for 180 min under inert atmosphere of nitrogen was performed. The results give a nearly alternating copolymer as evidenced from reactivity ratios (r(1) = 0.016, r(2) = 0.057) w.r.t. BPO; (r(1) = 0.017, r(2) = 0.052) w.r.t. p-ABTAY (i.e. r(1) = 0.0165 +/- 0.0005 and r(2) = 0.0545 +/- 0.0025 per initiator set) using Kelen-Tudos method. The FT-IR spectrum shows a band at 3026 cm(-1) due to the aromatic ring of polystyrene and an alcoholic band of linalool at 3408 cm(-1). H-1-NMR spectrum shows peaks at delta 7.0-7.7 ppm of -OH protons and peaks at delta 7.5-8.0 ppm due to phenyl protons of styrene. The system follows ideal kinetics i.e. Rp proportional to [LIN](1.0)[STY](1.0)[BpO](0.5)/[p-ABTAY](0.5). The overall energy of activation in the temperature range 75-85degreesC is 77.0 kJ mol(-1) and 90.0 kJ mol(-1), respectively. The values for Mark-Houwink constants for the functional copolymer has been evaluated as a = 0.40 and K = 1.60 X 10(-4) with the help of gel permeation chromatography (GPC). Alfrey-Price, Q and e parameters for linalool have been evaluated as Q(2) = 0.80; e(2) = 1.25 w.r.t. BPO and Q(2) = 0.90; e(2) = 1.54 w.r.t. p-ABTAY. Thermal properties of copolymers were investigated by thermogravimetric analysis (TGA) techniques. Copyright (C) 2004 John Wiley Sons, Ltd.