Novel Copolymers of Styrene and Dialkoxy Ring‐Substituted Methyl 2‐Cyano‐3‐phenyl‐2‐propenoates

Abstract

Electrophilic trisubstituted ethylene monomers, dialkoxy ring-substituted methyl 2-cyano-3-phenyl-2-propenoates, RC 6 H 3 CH5 5C(CN)CO 2 CH 3 , (where R is 2,3-, 2,4-, 2,5-, 3,4-, 3,5-dimethoxy, and 3-ethoxy-4-methoxy), were synthesized by the piperidine catalyzed Knoevenagel condensation of ring-substituted benzaldehydes and methyl cyanoacetate, and characterized by CHN elemental analysis, IR, 1 H-and 13 C-NMR. Novel copolymers of the ethylenes and styrene were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator (AIBN) at 708C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1 H-and 13 C-NMR, GPC, DSC, and TGA. High T g of the copolymers in comparison with that of polystyrene indicates a substantial decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. The gravimetric analysis indicated that the copolymers decompose in the 272-4008C range.

Synthesis and styrene copolymerization of novel trisubstituted ethylenes: 7. Ring-disubstituted 2-methoxyethyl phenylcyanoacrylates

“…The conversion of the copolymers was kept between 10 and 20% to minimize compositional drift (Table 1). Nitrogen elemental analysis showed that between 12.9 and 28.6 mol% of MEPA is present in the copolymers prepared at ST/MEPA = 3 (mol), which is indicative of relatively high reactivity of the MEPA monomers towards ST radical which is typical of ring-disubstituted phenylcyanoacrylates [18][19][20][21][22][23][24][25][26][27][28][29]. Since MEPA monomers do not homopolymerize, the most likely structure of the copolymers would be isolated MEPA monomer units alternating with short ST sequences (Scheme 2).…”

“…Earlier we have reported synthesis and styrene copolymerization a number of ringdisubstituted PCAs, such esters as methyl [18,19], ethyl [20], propyl [21][22][23], isopropyl [24][25][26], butyl [27,28], and isobutyl [29].…”

Synthesis and styrene copolymerization of novel trisubstituted ethylenes: 6. Methyl, halogen and oxy ring-disubstituted octyl phenylcyanoacrylates

“…The conversion of the copolymers was kept between 10 and 20% to minimize compositional drift (Table 1). Nitrogen elemental analysis showed that between 19.4 and 47.5 mol% of OPCA is present in the copolymers prepared at ST/ OPCA = 3 (mol), which is indicative of relatively high reactivity of the OPCA monomers towards ST radical which is typical of ring-substituted OPCA [18][19][20][21][22][23][24][25][26]. Since OPCA monomers do not homopolymerize, the most likely structure of the copolymers would be isolated OPCA monomer units alternating with short ST sequences (Scheme 2).…”

“…Thus, copolymerization of electrophylic TSE monomers having double bonds substituted with halo, cyano, and carbonyl groups and electron-rich monosubstituted ethylenes such as styrene, N-vinylcarbazole, and vinyl acetate [16][17][18] show a tendency toward the formation of alternating copolymers -thus suggesting a way of functionalization of commercial polymers via introduction of isolated monomer units in copolymers. Earlier we have reported synthesis and styrene copolymerization of a number of methyl, halogen, and oxy ring-disubstituted methyl [19][20][21], ethyl [22][23][24], propyl [25][26][27], isopropyl [28][29][30], butyl [31,32], isobutyl [33,34], and 2-methoxyethyl [35] PCAs.…”

Synthesis and copolymerization of novel oxy ring-substituted isopropyl cyanoarylacrylates

“…We have reported earlier synthesis and styrene copolymerization of oxy ring-substituted methyl [19][20][21][22][23][24], ethyl [25][26][27], propyl [28][29][30][31], butyl [32][33][34], isobutyl [35][36][37], methoxyethyl [38,39], and octyl [40][41][42] cyanoarylacrylates. In continuation of our exploration of novel trisubstituted ethylene compounds we have prepared isopropyl oxy ring-substituted cyanoarylacrylates, ICAA, RPhCH=C(CN)CO2CH(CH3)2, where R is 3-phenoxy, 4phenoxy, 2-benzyloxy, 3-benzyloxy, 4-benzyloxy, 4-acetyloxy, 3-acetyl, 4-acetyl, 4acetylamino, 4-methoxy-2-methyl, 4-methoxy-3-methyl, 3-ethoxy-4-methoxy, 3,4dibenzyloxy, 3-benzyloxy-4-methoxy, 4-benzyloxy-3-methoxy, 2,3-dimethyl-4-methoxy, 2,5-dimethyl-4-methoxy, 2,4-dimethoxy-3-methyl, 2,4-dimethoxy-6-methyl, 3,5-dimethoxy-4-hydroxy, and copolymerized with styrene.…”