Free radical co-polymerization of butylmethacrylate and linalool with a functional group as a pendant

Abstract

The radical co-polymerization of an acyclic monoterpenoid, namely linalool (LIN), with butylmethacrylate (BMA) in xylene at 80 ± 0.1°C for 1 h, using benzoylperoxide (BPO) as an initiator under the inert atmosphere of nitrogen has been carried out. The kinetics expression is: R p α [I] 0.5 [LIN]1.0 [BMA]1.0. The overall activation energy has been calculated as 60 kJ/mol. Bands at 3408 cm−1 and 1732 cm−1 in the FT-IR spectrum of the co-polymer(s) have indicated the presence of hydroxyl and ester groups of LIN and BMA, respectively. Further, the peaks at 7.0–7.7 δ and 3.2–4.0 δ, due to −OH proton of LIN and −OCH2 proton of BMA, respectively, have been observed in the 1H-NMR spectrum. The molecular weight (M v) and η int of the co-polymers have been measured with the help of gel-permeation chromatography in tetrahydrofuran at 25°C to calculate Mark–Houwink constants as α = 0.80 and K = 3.0 × 10−4. The alternating nature of the co-polymer is confirmed by reactivity ratios r 1 (BMA) = 0.016 and r 2 (LIN) = 0.003. The Alfrey–Price Q–e parameters for linalool have been calculated as Q 2 = 0.17 and e 2 = −1.29. Thermal decompositions of co-polymer are established with the help of thermogravimetric analysis. The mechanism of co-polymerization has been elucidated.