Synthesis and characterization of functional copolymers of citronellol and acrylamide

Abstract

The radical copolymerization of citronellol with acrylamide in xylene at (80 ± 10)°C for 1 h in the presence of benzoylperoxide follows ideal kinetics with bimolecular termination and results in the formation of an alternating copolymer as evidenced from the values of reactivity ratios as r1 (acrylamide) = 0.0045 and r2 (citronellol) = 0.0005, which have been calculated by Kelen–Tudos method. The overall activation energy is computed as 44 kJ/mol. The IR spectrum of the copolymer shows the presence of bands at 3427 cm−1 due to alcoholic group and 1710 cm−1 due to amide group. The 1H NMR spectrum of the copolymer shows peaks between 6.3 and 7δ due to amide group (> CO stretching) and between 7 and 7.7δ due to alcoholic group. The values of Mark–Houwink constant for present copolymer system have been evaluated as α = 0.33 and K = 2.3 × 10−1 with the help of gel permeation chromatography. The Alfrey-price, Q–e parameters for citronellol have been calculated as 0.43 and 1.07. The copolymer is highly thermally stable and has a glass transition temperature (Tg) of 102°C as evaluated from differential scanning calorimetry studies. The mechanism has also been elucidated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4908–4914, 2006