S. Kobatake, B. Yamada, S. Aoki
1995
Citations
0
Influential Citations
11
Citations
Journal
Polymer
Abstract
Methyl 2-(acyloxymethyl)acrylates [CH 2 =C(CH 2 OCOR)COOCH 3 ; R = CH 3 , CH 2 CH 2 CH 3 , CH(CH 3 ) 2 and C(CH 3 ) 3 ] were prepared by nucleophilic substitution of methyl 2-(bromomethyl)acrylate with the desired carboxylic acid in the presence of triethylamine at ambient temperature. These particular monomers homopolymerize faster than methyl methacrylate (MMA) despite the presence of large 2-substituents. Propagating radicals of the acyloxymethylacrylates in benzene in a homogeneous system were detected and quantified. The rate constants of propagation ( k p ) and termination ( k p ) for methyl 2-(acetoxymethyl)-acrylate (MAcMA) at 60 °C, which were determined based on the quantification of propagating radical, are smaller than those of MMA by factors of 1.5 and 20, respectively. The steric hindrance of the 2-substituent reduced k t more significantly than k p , leading to polymerization to a higher molecular weight. The 2-(acyloxymethyl)acrylates can be noted to yield homopolymers through steric hindrance-assisted polymerization . Slightly higher reactivities for MAcMA than MMA were estimated in the copolymerization with styrene because of the effect of the electronegative character of the oxygen atom on the acetoxyl group.