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Summary: Methyl 2-cyano-3-dihalophenyl-2-propenoates, R2C6H3CH=C(CN)CO2CH3 (R2= 2,4-difluoro, 2,5-difluoro, 2,6-difluoro, 3,4-difluoro, 3,5-difluoro, and 2-chloro-6-fluoro), were prepared by the piperidine catalyzed Knoevenagel condensation of corresponding disubstituted benzaldehydes and methyl cyanoacetate. Novel copolymers of the propenoates and styrene were prepared at equimolar monomer feed by solution copolymerization in the presence of a radical initiator. The order of relative reactivity (1/r 1) was 2,5-difluoro (2.11) > 2,6-difluoro (1.84) > 3,5-difluoro (1.71) > 2,4-difluoro (1.4) > 3,4-difluoro (0.65) > 2-chloro-6-fluoro (0.59). The copolymers were characterized by IR, 1H and 13C NMR, GPC, DSC and TGA. High glass transition temperatures of the copolymers compared that of polystyrene indicates a substantial decrease in chain mobility of the copolymers due to the high dipolar character of the trisubstituted ethylene monomer unit.

Electrophilic trisubstituted ethylenes, ring-disubstituted methyl 2-cyano-3-phenyl-2-propenoates, RCH=C(CN)CO2CH3(where R = 2,3-dichlorophenyl, 2,4-dichlorophenyl, 2,6-dichlorophenyl, 3,4-dichlorophenyl, 4-chloro-3-nitrophenyl, 5-chloro-2-nitrophenyl, 2-chloro-6-fluoro), were prepared and characterized. All the propenoates, except methyl 2-cyano-3-(4-chloro-3-nitrophenyl)-2-propenoate, were copolymerized with styrene (M1) in solution with radical initiation (AIBN) at 70°C. The compositions of the copolymers were calculated from nitrogen analysis and the structures were analyzed by IR, 1H-, and 13C-NMR. The order of relative reactivity (1/r1) for the monomers is 2,4-dichloro (2.1) = 3,4-dichloro (2.1) > 2,6-dichloro (0.8) = 2,3-dichloro (0.8) > 2-chloro-6-fluoro (0.6) > 5-chloro-2-nitro (0.2). The high glass transition temperatures of the copolymers (> 190°C) in comparison with that of polystyrene indicate a substantial decrease in the chain mobility of the copolymers due to the high dipolar character of the trisubstituted monomer unit. Gravimetric analysis indicated that the copolymers decompose in the range 300-400°C.

Electrophilic trisubstituted ethylenes, phenyl-substituted methyl 2-cyano-3-phenyl-2-propenoates, RC6H4CH=C(CN)CO2CH3(where R = p-CN, p-NHCOCH3, o-NO2'p-NO2), were prepared and characterized. The feasibility of copolymerization of the monomers with styrene (M1) was investigated in solution at an equimolar feed ratio in the presence of a radical initiator, 2,2-azobisisobutyronitrile (AIBN), at 80°C. Nitro-substituted propenoates did not form styrene copolymers. The relative reactivity (1/r1) for p-CN and p-NHCOCH3substituted monomers was 41.2 and 0.38, respectively.

Fumarate-based polyesters were prepared by the transesterification polycondensation of diethyl fumarate and diols: (±)-1,2-propanediol, (S)-(+)-1,2-propanediol, 2-methyl-1,3-propanediol, and 2,2-dimethyl-1,3-propanediol. Different polyester microstructures were observed by ¹H-NMR and ¹³C-NMR spectroscopy when the reaction was conducted in the presence of p-toluenesulfonic acid monohydrate or metal containing catalysts—aluminum trichloride, titanium tetrachloride, titanium tetrabutoxide, and zinc chloride. The extent of formation of branched structures associated with hydroxyl end groups' addition to the unsaturated polyester double bonds depends on the acidity of the catalyst. The bone cement composites were prepared by mixing the fumarate polyesters with an inorganic filler, CaSO4 · 2H2O, and N-vinyl pyrrolidone, which crosslinks on the addition of a radical initiator, benzoyl peroxide, at ambient temperatures. The compressive strength and hydrolytic stability of the cement compositions was correlated with structure of the polyesters. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 1123–1137, 1997

Summary: Halogen phenyl-substituted methyl 2-cyano-3-phenyl-2-propenoates, RC6H4CH=C(CN)CO2CH3 (R= 2-fluoro, 3-fluoro, 2-bromo, and 3-bromo), were prepared by the piperidine catalyzed Knoevenagel condensation of corresponding substituted benzaldehydes and methyl cyanoacetate. Novel copolymers of the propenoates and styrene were prepared at equimolar monomer feed by solution copolymerization in the presence of a radical initiator. The order of relative reactivity (1/r 1) was 3Br (3.02) > 2Br (2.63) > 3F (1.84) > 2F (1.66). High glass transition temperatures of the copolymers compared that of polystyrene indicates a substantial decrease in chain mobility of the copolymers due to the high dipolar character of the trisubstituted ethylene monomer unit.