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1.
Electrophilic trisubstituted ethylene monomers, ring-substituted methyl 2-cyano-3-phenyl-2-propenoates, RC6H4CH?C(CN) CO2CH3 (where R is 4-C2H5O, 4-C3H7O, 4-C4H9O, 3-C6H5O, and 3-CN), were prepared and copolymerized with styrene. The monomers were synthesized by the piperidine catalyzed Knoevenagel condensation of ring-substituted benzaldehydes and methyl cyanoacetate, and characterized by CHN elemental analysis, IR, 1H- and 13C-NMR. All the propenoates 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 3-CN (1.21) > 3-C6H5O (1.16) > 4-C2H5O (0.94) > 4-C3H7O (0.8305) > 4-C4H9O (0.616). The high T g's of the copolymers (> 130°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.  相似文献   

2.
Abstract

Electrophilic trisubstituted ethylenes, ring‐substituted ethyl 2‐cyano‐3‐phenyl‐2‐propenoates, RC6H4CH?C(CN)CO2C2H5 (where R is 2‐CH3, 3‐CH3, 4‐CH3, 2‐OCH3, 3‐OCH3, and 4‐OCH3) were prepared and copolymerized with styrene (ST). The monomers were synthesized by the piperidine catalyzed Knoevenagel condensation of ring‐substituted benzaldehydes and ethyl cyanoacetate, and characterized by CHN analysis, IR, 1H and 13C NMR. All the ethylenes were copolymerized with ST (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/r 1) for the monomers is 3‐OCH3 (0.88)?>?4‐CH3 (0.71)?>?2‐OCH3 (0.68)?>?3‐CH3 (0.55)?>?2‐CH3 (0.47)?>?4‐OCH3 (0.40). Higher T g of the copolymers in comparison with that of polystyrene indicates a decrease in chain mobility of the copolymer due to the high dipolar character of the TSE structural unit. Gravimetric analysis indicated that the copolymers decompose in the 257–287°C range.  相似文献   

3.
Novel copolymers of trisubstituted ethylene monomers, alkoxy ring-substituted 2-phenyl-1,1-dicyanoethylenes, RC6H4CH = C(CN)2 (where R is 2-methoxy, 3-methoxy, 4-methoxy, 2-ethoxy, 3-ethoxy, 4-ethoxy, 4-propoxy, 4-buthoxy, 4-hexyloxy) and 4-fluorostyrene were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator (ABCN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C-NMR. The order of relative reactivity (1/r 1) for the monomers is 2-methoxy (1.5) > 4-ethoxy (1.0) > 4-methoxy (0.8) > 3-ethoxy (0.7) = 3-methoxy (0.7) > 4-hexyloxy (0.6) = 2-ethoxy (0.6) > 4-butoxy (0.5) = 4-propoxy (0.5). High T g of the copolymers, in comparison with that of poly(4-fluorostyrene) indicates a substantial decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in 284–500°C range with residue (5–9% wt), which then decomposed in the 500–800°C range.  相似文献   

4.
Novel copolymers of trisubstituted ethylene monomers, alkyl and alkoxy ring-substituted 2-phenyl-1,1-dicyanoethylenes, RC6H4CH=C(CN)2 (where R is 2-ethyl, 4-i-propyl, 4-butyl, 4-i-butyl, 4-t-butyl, 2-ethoxy, and 4-hexyloxy) and styrene were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator (ABCN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C-NMR. The order of relative reactivity (1/r 1) for the monomers is 4-t-butyl (1.45) > 4-i-propyl (1.38) > 2-ethyl (1.37) > 4-hexyloxy (1.33) > 4-i-butyl (1.24) > 2-ethoxy (1.13) > 4-butyl (1.04). 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. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200–500°C range with residue (1–10% wt.), which then decomposed in the 500–800°C range.  相似文献   

5.
Novel copolymers of trisubstituted ethylene monomers, ring-substituted 2-phenyl-1,1-dicyanoethylenes, RC6H2CH=C(CN)2 (where R is 2,4-(CH3O)2-3-CH3, 2,3,4-(CH3O)3, 2,4,5-(CH3O)3, 2,4,6-(CH3O)3, 3,4,5-(CH3O)3, 6-Br-3,4-(CH3O)2), 2,3,5-Cl3, 2,3,6-Cl3 and 4-fluorostyrene were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator (ABCN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C-NMR. The order of relative reactivity (1/r 1) for the monomers is 3,4,5-(CH3O)3(10.6) > 2,4,6-(CH3O)3(9.3) > 2,4,5-(CH3O)3 (5.4) > 2,3,4-(CH3O)3 (4.4) > 6-Br-3,4-(CH3O)2 (3.2) > 2,3,5-Cl3 (1.5) > 2,3,6-Cl3 (1.0) > 2,4-(CH3O)2-3-CH3 (0.7). High T g of the copolymers, in comparison with that of poly(4-fluorostyrene) indicates a substantial decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200–400°C range with residue, which then decomposed in the 400–800°C range.  相似文献   

6.
Novel copolymers of trisubstituted ethylene monomers, halogen ring-disubstituted 2-phenyl-1,1-dicyanoethylenes, RC6H3CH= C(CN)2 (where R is 2,3-Cl2, 2,4-Cl2, 2,6-Cl2, 3,4-Cl2, 3,5-Cl2, 2-Cl-4-F, 2-Cl-6-F, 3-Cl-4-F) and 4-fluorostyrene were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator (ABCN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C-NMR. The order of relative reactivity (1/r 1) for the monomers is 2-Cl-4-F (2.42) > 3,4-Cl2(2.40) > 2,4-Cl2(1.97) > 2-Cl-6-F (1.86) > 3-Cl-4-F (1.68) > 2,3-Cl2 (0.89) > 3,5-Cl2 (0.70) > 2,6-Cl2 (0.47). High Tg of the copolymers, in comparison with that of poly(4-fluorostyrene) indicates a substantial decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. Softening of the copolymers started in 194–216°C range. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 290–400°C range with residue, which then decomposed in 400–800°C range.  相似文献   

7.
Novel copolymers of trisubstituted ethylene monomers, ring-substituted 2-phenyl-1,1-dicyanoethylenes, RC6H2CH=C(CN)2 (where R is 4-C6H5O, 2-C6H5CH2O, 3,4-(C6H5CH2O)2, 2-C6H5CH2O-3-CH3O, 3-C6H5CH2O-4-CH3O, 2-Cl-6-NO2, 4-Cl-3-NO2, 5-Cl-2-NO2) and 4-fluorostyrene were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator (ABCN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C-NMR. The order of relative reactivity (1/r 1) for the monomers is 3,4-(C6H5CH2O)2(31.0) > 2-C6H5CH2O-3-CH3O (24.8) > 3-C6H5CH2O-4-CH3O (15.2) > 4-C6H5O (3.1) > 4-Cl-3-NO2 (1.9) > 2-Cl-6-NO2 (1.6) > 5-Cl-2-NO2 (1.5) > 2-C6H5CH2O (1.4). High Tg of the copolymers, in comparison with that of poly(4-fluorostyrene) indicates a substantial decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 270-400°C range with residue, which then decomposition in 400–800°C range.  相似文献   

8.
Novel copolymers of trisubstituted ethylene monomers, ring-substituted 2-phenyl-1,1-dicyanoethylenes, RC6H3CH?C(CN)2 (where R is 2,3-(CH3O)2, 2,4-(CH3O)2, 2,5-(CH3O)2, 2,6-(CH3O)2, 3,4-(CH3O)2, and 3,5-(CH3O)2 and 4-fluorostyrene were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator (ABCN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C-NMR. The order of relative reactivity (1/r 1) for the monomers is 2,6-(CH3O)2(2.8) > 2,5-(CH3O)2(2.5) > 2,3-(CH3O)2 (2.1) > 3,5-(CH3O)2 (1.8) > 3,4-(CH3O)2 (0.9) > 2,4-(CH3O)2 (0.7). High Tg of the copolymers, in comparison with that of poly(4-fluorostyrene) indicates a substantial decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 250–400°C range with residue, which then decomposition in 400–800°C range.  相似文献   

9.
Novel copolymers of trisubstituted ethylene monomers, ring-substituted 2-phenyl-1,1-dicyanoethylenes, RC6H4CH = C(CN)2 (where R is 2-F, 2-CN, 3-CN, 4-CN, 3-C6H5O, 4-C6H5O, 2-C6H5CH2O, 3-C6H5CH2O, 4-C6H5CH2O, 4-CH3CO2, 4-CH3CONH, 4-(CH3)2N) and styrene were prepared by solution copolymerization in the presence of a radical initiator (ABCN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C-NMR. The order of relative reactivity (1/r 1) for the monomers is 4-(CH3)2N (3.35) > 4-C6H5CH2O (3.1) > 2-C6H5CH2O (1.77) > 3-C6H5CH2O (1.72) > 4-C6H5O (1.70) > 4-CH3CO2 (1.58) > 2-F (1.11) > 3-C6H5O (0.90) > 3-CN (0.88) > 2-CN (0.86) > 4-CH3CONH (0.84) > 4-CN (0.76). Relatively high Tg of the copolymers in comparison with that of polystyrene indicates a decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200–500°C range with residue (1–10% wt), which then decomposed in the 500–800°C range.  相似文献   

10.
Novel copolymers of trisubstituted ethylene monomers, ring-substituted 2-phenyl-1,1-dicyanoethylenes, RC6H4CH=C(CN)2 (where R is 4-dimethylamino, 4-diethylamino, 3-phenoxy, 3-benzyloxy, 4-benzyloxy, 4-acetoxy, 2-cyano, 3-cyano, and 4-cyano) and 4-fluorostyrene were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator (ABCN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C-NMR. The order of relative reactivity (1/r 1) for the monomers is 3-benzyloxy (2.9) > 4-cyano (2.7) > 3-phenoxy (1.9) > 4-acetoxy (1.8) > 3-cyano (1.7) > 2-cyano (1.6) > 4-benzyloxy (0.6) > 4-dimethylamino (0.4) = 4-diethylamino (0.4). High T g of the copolymers, in comparison with that of poly (4-fluorostyrene) indicates a substantial decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 290–400°C range with residue, which then decomposition in 400–800°C range.  相似文献   

11.
Novel copolymers of trisubstituted ethylene monomers, alkyl ring-substituted 2-phenyl-1,1-dicyanoethylenes, RC6H4CH = C(CN)2 (where R is 2-methyl, 3-methyl, 4-methyl, 4-ethyl, 4-i-propyl, 4-butyl, 4-i-butyl, and 4-t-butyl) and 4-fluorostyrene were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator (ABCN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C-NMR. The order of relative reactivity (1/r 1) for the monomers is 4-ethyl (42.6) > 4-butyl (29.4) > 4-t-butyl (26.7) > 4-i-butyl (1.6) > 4-i-propyl (1.29) > 3-methyl (1.26) > 2-methyl (0.8) > 4-methyl (0.4). High T g of the copolymers, in comparison with that of poly(4-fluorostyrene) indicates a substantial decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in 183–500°C range with residue (5–30% wt.), which then decomposed in the 500–800°C range.  相似文献   

12.
Novel copolymers of trisubstituted ethylene monomers, ring-disubstituted 2-phenyl-1,1-dicyanoethylenes, RC6H3CH=C(CN)2 (where R = 3-Br-4-CH3O, 5-Br-2-CH3O, 2-F-5-CH3, 2-F-6-CH3, 3-F-2-CH3, 3-F-4-CH3, 4-F-2-CH3, 4-F-3-CH3) and 4-fluorostyrene were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator (ABCN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C-NMR. The order of relative reactivity (1/r 1) for the monomers is 3-F-4-CH3(1.64) > 5-Br-2-CH3O (1.62) > 3-Br-4-CH3O (1.36) > 4-F-2-CH3(1.3) > 4-F-3-CH3(1.26) > 3-F-2-CH3(1.11) > 2-F-5-CH3 (0.98) > 2-F-6-CH3 (0.97). High Tg of the copolymers, in comparison with that of poly(4-fluorostyrene) indicates a substantial decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 290–400°C range with residue, which then decomposed in 400–800°C range.  相似文献   

13.
Novel copolymers of trisubstituted ethylene monomers, ring-substituted 2-phenyl-1,1-dicyanoethylenes, RC6H3CH═C(CN)2 (where R is 2-bromo,3-bromo, 3-chloro, 2,3-dichloro, 2-chloro-6-fluoro, 2,6-difluoro, 3,4-difluoro, and 3,5-difluoro) and styrene were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator (AIBN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C-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 200–800°C range.  相似文献   

14.
Novel copolymers of trisubstituted ethylene monomers, ring-substituted 1,1-dicyano-2-(1-naphthyl)ethylenes, RC10H6CH?C(CN)2 (where R is H, 2-OCH3, 4-OCH3) and 4-fluorostyrene were prepared by solution copolymerization in the presence of a radical initiator (ABCN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C-NMR. The order of relative reactivity (1/r 1) for the monomers is (5.86) > 2-CH3O (4.28) > 4-CH3O (2.87). Relatively high Tg of the copolymers in comparison with that of poly(4-fluorostyrene) indicates a decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200–500°C range with residue (7.3–7.7% wt.), which then decomposed in the 500–800°C range.  相似文献   

15.
Novel copolymers of trisubstituted ethylene monomers, fluorine ring-substituted 2-phenyl-1,1-dicyanoethenes, RC6H4CH[dbnd]C(CN)2 (where R is 2-F, 3-F, and 4-F) and 4-fluorostyrene were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator (ABCN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C-NMR. High T g of the copolymers, in comparison with that of poly(4-fluorostyrene) 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 decomposed in two stages in the range 210–600°C.  相似文献   

16.
Novel electrophilic trisubstituted ethylene monomers, oxy ring substituted 2-cyano-3-phenyl-2-propenamides, RC6H4CH? C(CN)CONH2 (where R is 2-CH3O, 3-CH3O, 4-CH3O, 2-C2H5O, 3-C2H5O, 4-C2H5O, 4-C3H7O, 4-C4H9O, 4-C6H13O, 3-C6H5O, 4-C6H5O, 3-C6H5CH2O, 4-C6H5CH2O), were synthesized by potassium hydroxide catalyzed Knoevenagel condensation of ring-substituted benzaldehydes and cyanoacetamide, and characterized by CHN elemental analysis, IR, 1H- and 13C-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 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H- and 13C-NMR, GPC, DSC, and TGA. High Tg 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. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200–500°C range with residue (0.2–1.2 wt%), which then decomposed in the 500–800°C range.  相似文献   

17.
Novel trisubstituted ethylenes, oxy ring-substituted butyl 2-cyano-3-phenyl-2-propenoates, RPhCH=C(CN)CO2C4H9 (where R is 2-methoxy, 3-methoxy, 4-methoxy, 2-ethoxy, 3-ethoxy, 4-ethoxy, 4-propoxy, 4-butoxy, 4-hexyloxy, 3-phenoxy) were prepared and copolymerized with styrene. The monomers were synthesized by the piperidine catalyzed Knoevenagel condensation of oxy ring-substituted benzaldehydes and butyl cyanoacetate and characterized by CHN elemental analysis, IR, 1H- and 13C-NMR. All the ethylenes were copolymerized with styrene (M1) in solution with radical initiation (ABCN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C-NMR, GPC, DSC, and TGA. The order of relative reactivity (1/r1) for the monomers is 4-methoxy (6.56) > 3-methoxy (2.97) > 2-methoxy (2.72) > 4-butoxy (2.20) > 3-ethoxy (2.18) > 4-propoxy (2.15) > 4-hexyloxy (1.78) > 4-ethoxy (1.66) > 2-ethoxy (1.48) > 3-phenoxy (1.29). Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200-500°C range with residue (0.8–3.6% wt.), which then decomposed in the 500–800°C range.  相似文献   

18.
Novel electrophilic trisubstituted ethylene monomers, oxy ring-disubstituted 2-cyano-3-phenyl-2-propenamides, RC6H3CH? C(CN)CONH2 (where R is 2,3-(CH3O)2, 2,4-(CH3O)2, 2,5-(CH3O)2, 2,6-(CH3O)2, 3,4-(CH3O)2, 3,5-(CH3O)2, 3-CH3?4-CH3O, 3-C2H5O-4-CH3O, 3,4-(C6H5CH2O)2, 2-C6H5CH2O-3-CH3O, 3-C6H5CH2O-4-CH3O, 4-C6H5CH2O-3-CH3O) were synthesized by potassium hydroxide catalyzed Knoevenagel condensation of ring-disubstituted benzaldehydes and cyanoacetamide, and characterized by CHN analysis, IR, 1H- and 13C-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 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H- and 13C-NMR. High Tg of the copolymers in comparison with that of polystyrene indicates a decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 300–500°C range with residue (2–9% wt), which then decomposed in the 500–800°C range.  相似文献   

19.
Electrophilic trisubstituted ethylenes, ring-disubstituted ethyl 2-cyano-3-phenyl-2-propenoates, RPhCH?C(CN)CO2C2H5 (where R is 3-Br-4-CH3O, 5-Br-2-CH3O, 3-F-2- CH3, 3-F-4-CH3, 4-F-2-CH3, 4-F-3-CH3, 5-F-2-CH3, 2-Cl-5-NO2, 2-Cl-6-NO2, 4-Cl-3- NO2) were prepared and copolymerized with styrene. The monomers were synthesized by the piperidine catalyzed Knoevenagel condensation of ring-disubstituted benzaldehydes and ethyl cyanoacetate, and characterized by CHN analysis, IR, 1H and 13C-NMR. All the ethylenes were copolymerized with styrene (M1) in solution with radical initiation (ABCN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C-NMR. The order of relative reactivity (1/r 1) for the monomers is 5-Br-2-CH3O (1.02) > 4-Cl-3-NO2 (0.93) > 3-F-4-CH3 (0.81) > 2-Cl-6-NO2 (0.77) > 2-Cl-5-NO2 (0.71) > 3-Br-4-CH3O (0.66) > 4-F-3-CH3 (0.60) > 3-F-2-CH3 (0.38) > 4-F-2-CH3 (0.31) > 5-F-2-CH3 (0.16). Relatively high Tg of the copolymers in comparison with that of polystyrene indicates a decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 250–500°C range with residue (2–26% wt.), which then decomposed in the 500–800°C range.  相似文献   

20.
Novel trisubstituted ethylenes, ring-disubstituted butyl 2-cyano-3-phenyl-2-propenoates, RPhCH?C(CN)CO2C4H9 (where R is 2-bromo-5-methoxy, 3-bromo-4-methoxy, 5-bromo-2-methoxy, 2-chloro-3-methoxy, 3-chloro-4-methoxy, 2-chloro-6-methyl, 3-chloro-4-methyl, 2-fluoro-4-methoxy) were prepared and copolymerized with styrene. The monomers were synthesized by the piperidine catalyzed Knoevenagel condensation of ring-substituted benzaldehydes and butyl cyanoacetate, and characterized by CHN analysis, IR, 1H and 13C-NMR. All the ethylenes were copolymerized with styrene in solution with radical initiation (ABCN) at 70°C. The compositions of the copolymers were calculated from nitrogen analysis and the structures were analyzed by IR, 1H and 13C-NMR. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200-500ºC range with residue (1-6% wt.), which then decomposed in the 500–800ºC range.  相似文献   

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