ABSTRACT:Copolymerizations of 2-amino-4-(N-alkylanilino )-6-isopropenyl-1,3,5-triazines with styrene, methyl methacrylate and methyl acrylate were carried out using azobisisobutyronitrile as an initiator. Alkyl groups were propyl, hexyl, octyl, decyl, dodecyl, tetradecyl, hexadecyl, octadecyl, and docosyl. Copolymerization parameters (ri, r2, Q, and e) were determined for these monomers. No significant effect of alkyl chain length on the copolymrization parameters could be observed. Relationships between glass transition temperatures and composition of the copolymers were investigated. Crystallization exothermic and melting endothermic peaks due to the side-chains were observed in the DSC thermograms of the comb-like copolymers containing octadecyl and docosyl groups. The crystallinity of the side-chains decreased with increasing content of styrene or methyl methacrylate in the copolymers.
KEY WORDSIsopropenyltriazines / Long Alkyl Group / Copolymerization Parameters / Glass Transition Temperature / Comb-Like Copolymer / Side-Chain Crystallization / Polymers containing long alkyl side-chains, so-called comb-like polymers, have attracted much attention due to specific properties such as side-chain crystallization, 1 -3 peculiar mechanical properties, 3 ability of liquid crystal formation,4-7 and formation of LangmuirBlodgett film. 8 Furthermore, comb-like copolymers prepared by the copolymerization of long-chain monomers with common comonomers have been studied to improve solubility and to increase flexibility by internal plasticization. [9][10][11][12][13][14][15] and property of the copolymers. 1 7 -22 As a part of these studies, this paper deals with copolymerization parameters of isopropenyl-1,3,5-triazines containing long alkyl groups, and with the T 8 s and the side-chain crystallization of the resulting comb-like copolymers.In a previous paper, 16 we reported the synthesis and polymerization of 2-amino-4-(Nn-alkylanilino )-6-isopropenyl-1,3,5-triazines, and found that long alkyl side-chains in the resulting comb-like polymers could be crystallized below the glass transition temperature (T 8 ) of the main-chain. On the other hand, we have studied substituent effects of isopropenyl-1,3,5-triazines on copolymerization behaviorThe structures and abbreviations of isopropenyl-1,3,5-triazines used in this study are shown in Figure 1.