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1.
Gregory B. Kharas Sonia E. Chavez Harrison S. Browning Jennifer A. Sepe Mario E. Romanelli Melissa K. Susnis 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(10):751-755
Electrophilic trisubstituted ethylenes, ring-disubstituted methyl 2-cyano-3-phenyl-2-propenoates, RPhCH?C(CN)CO2CH3, where R is 2,5-dichloro, 3,5-dichloro, 2,3-difluoro, 3-chloro-2-fluoro, 3-chloro-4-fluoro, 4-chloro-3-fluoro, 2-chloro-5-nitro, and 2-chloro-6-nitro were prepared and copolymerized with styrene. The monomers were synthesized by the piperidine catalyzed Knoevenagel condensation of ring-disubstituted benzaldehydes and methyl 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 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 4-Cl-3-F (4.87) > 2,3-F2 (4.49) > 3-Cl-4-F (3.50) > 3-Cl-2-F (2.96) > 2-Cl-5-NO2 (2.02) > 2,5-Cl2 (1.54) > 2-Cl-6-NO2 (1.00) > 3,5-Cl2 (0.41). 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 200–500ºC range with residue (1.5–34.5% wt), which then decomposed in the 500-800ºC range. 相似文献
2.
Gregory B. Kharas Katherine T. Flynn Benjamin L. Hill Mustafa R. Ishaq Darin A. Kopp Brittany G. Koroll 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(2):95-99
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
3.
Gregory B. Kharas Hui Feng Hemal S. Bhavsar Sara M. Rocus William S. Schjerven Ahlam Shahbain 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(2):90-94
Novel trisubstituted ethylene monomers, halogen ring-trisubstituted methyl 2-cyano-3-phenyl-2-propenoates, RPhCH=C(CN)CO2CH3, where R is 4-bromo-2,6-difluoro, 3-chloro-2,6-difluoro, 4-chloro-2,6-difluoro, 2,3,5-trichloro, 2,3,6-trichloro, and 2,4,5-trifluoro, were prepared and copolymerized with styrene. The monomers were synthesized by the piperidine catalyzed Knoevenagel condensation of halogen ring-trisubstituted benzaldehydes and methyl 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 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-Cl-2,6-F2 (4.2) > 4-Cl-2,6-F2 (3.9) > 4-Br-2,6-F2 (1.8) > 2,3,5-Cl3 (1.1) > 2,4,5-F3 (0.9) > 2,3,6-Cl3 (0.5). 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 (3.1–3.9% wt), which then decomposed in the 500–800°C range. 相似文献
4.
Gregory B. Kharas Eric S. Molina Brittany M. Fitzpatrick Mathew C. Francis Christopher Gallardo Jessica L. Gehle 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(4):370-374
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
5.
Gregory B. Kharas Jessica Bates Alex T. Boyd James N. Burke Jenna L. Crosby Shawn B. Sundquist 《高分子科学杂志,A辑:纯化学与应用化学》2017,54(6):372-375
Novel trisubstituted ethylenes, ring-disubstituted propyl 2-cyano-3-phenyl-2-propenoates, RPhCH = C(CN)CO2C3H7 (where R is 2-bromo-4-methyl, 2-chloro-6-methyl, 3-chloro-4-methyl, 2,5-dibromo, 3,5-dibromo, 2,3-dichloro, and 2,4-dichloro) were prepared and copolymerized with styrene. The monomers were synthesized by the piperidine catalyzed Knoevenagel condensation of ring-substituted benzaldehydes and propyl cyanoacetate and characterized by CHN elemental analysis, IR, 1H and 13C-NMR. All the ethylenes were copolymerized with styrene 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. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200-500°C range with residue (7-12% wt.), which then decomposed in the 500-800°C range. 相似文献
6.
Gregory B. Kharas Benjamin L. Hill Jessica Crespo Ami I. Hsieh Jill Ippolito Jose Juares 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(2):89-93
Electrophilic trisubstituted ethylenes, dihalogen ring-substituted ethyl 2-cyano-1-oxo-3-phenyl-2-propenylcarbamates, RC6H3 CH = C(CN)CONHCO2C2H5(where R is 2,3-diCl, 2,4-diCl, 2,6-diCl, 3,4-diCl, 3,5-diCl, and 2-Cl-6-F, were prepared and copolymerized with styrene. The monomers were synthesized by the piperidine catalyzed Knoevenagel condensation of ring-substituted benzaldehydes and N-cyanoacetylurethane, 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 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 2,4-diCl (4.4) > 2,6-diCl (3.6) > 2,3-diCl (3.4) = 3,4-diCl (3.4) > 2-Cl-6-F (2.7) > 3,5-diCl (2.0). High T g of the copolymers in comparison with that of polystyrene indicates decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene structural unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in 270–420°C with residue (5–13% wt), which then decomposed in the 420–650°C range. 相似文献
7.
Gregory B. Kharas Emi Hanawa Benjamin L. Hill Katherine T. Flynn Wilbert-John Alvarez Brigette A. Baronti 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(6):428-432
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.
Gregory B. Kharas Alexander A. Delgado Karen Aco Louise M. Cardenas Miriam L. Lopez Akami D. Mazerat 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(4):365-369
Electrophilic trisubstituted ethylenes, dihalogen ring-substituted ethyl 2-cyano-3-phenyl-2-propenoates, RPhCH?C(CN)CO2C2H5 (where R is 2,3-diCl, 2,4-diCl, 2,6-diCl, 3,4-diCl, 3,5-diCl, 2,3-diF, 2,4-diF, 2,5-diF, 2,6-diF, 3,4-diF, 3,5-diF) were prepared and copolymerized with styrene. 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 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 3,4-diCl (1.89) > 2,4-diCl (1.84) > 3,5-diCl (1.40) > 2,6-diCl (1.21) > 2,4-diF (1.16) > 2,3-diF (1.01) > 2,3-diCl (0.74) > 3,4-diF (0.52) > 2,6-diF (0.45) > 3,5-diF (0.44) > 2,5-diF (0.33). 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 (2.6–5.0 wt%), which then decomposed in the 500–800°C range. 相似文献
9.
Gregory B. Kharas Najib J. Ayman Rocelyn Calso Lydia Jordanovic Fiona Lane Jevgenijs Lusciks 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(6):412-416
Novel electrophilic trisubstituted ethylene monomers, halo ring-disubstituted 2-cyano-3-phenyl-2-propenamides, RPhCH = C(CN)CONH2, where R is 2,3-difluoro, 2,4-difluoro, 2,5-difluoro, 2,6-difluoro, 3,4-difluoro, 3,5-difluoro, 2-chloro-4-fluoro, 3-chloro-2-fluoro, 3-chloro-4-fluoro were prepared and copolymerized with styrene. The monomers 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, 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. 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 (10–14 wt%), which then decomposed in the 500–800°C range. 相似文献
10.
Gregory B. Kharas William S. Schjerven Fatimah A. S. Aldakheel Edgar J. Crespo Zachary M. Gaskell Khalifa J. M. Jordan 《高分子科学杂志,A辑:纯化学与应用化学》2017,54(2):67-70
Novel trisubstituted ethylenes, ring-disubstituted propyl 2-cyano-3-phenyl-2-propenoates, RPhCH = C(CN)CO2C3H7 (where R is 2,5-dichloro, 2,6-dichloro, 3,4-dichloro, 2,3-difluoro, 2,4-difluoro, 2,5-difluoro, 2,6-difluoro) were prepared and copolymerized with styrene. The monomers were synthesized by the piperidine catalyzed Knoevenagel condensation of ring-substituted benzaldehydes and propyl 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. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200–500°C range with residue (1.2–3.1% wt.), which then decomposed in the 500–800°C range. 相似文献
11.
Gregory B. Kharas Hui Feng Isma S. Shouib Connie Tong Andrew Tsang Darcy Velazquez 《高分子科学杂志,A辑:纯化学与应用化学》2016,53(1):1-5
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
12.
Gregory B. Kharas Emi Hanawa Aime Norris Barbara Cissell Karen Skrypek Carolyn Holl 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(12):967-971
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
13.
Gregory B. Kharas Sara M. Rocus Haley E. Aynessazian Zachary L. Christy-Aronson Iris C. Chaoui-Boudrane Rachel M. Lange 《高分子科学杂志,A辑:纯化学与应用化学》2016,53(6):335-339
Electrophilic trisubstituted ethylenes, halogen ring-disubstituted butyl 2-cyano-3-phenyl-2-propenoates, RPhCH?C(CN)CO2C4H9 where R is 2-chloro-4-fluoro, 2-chloro-6-fluoro, 3-chloro-2-fluoro, 3-chloro-4-fluoro, 4-chloro-3-fluoro, 2-fluoro-5-iodo, 3-(3,4-dichlorophenoxy), 4-(2,4-dichlorophenoxy) 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 (M1) 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 200–500°C range with residue (1.7–6.8% wt), which then decomposed in the 500–800°C range. 相似文献
14.
Gregory B. Kharas Teresa Spann Rami Dawood Sarah Malik Isaac J. Deleon Maura A. Estes 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(7):499-503
Novel trisubstituted ethylenes, alkyl ring-substituted butyl 2-cyano-3-phenyl-2-propenoates, RPhCH=C(CN)CO2C4H9 (where R is 2-methyl, 3-methyl, 4-methyl, 2-ethyl, 4-ethyl, 4-butyl, 4-t-butyl, 4-i-butyl) 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 (M1) 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. The order of relative reactivity (1/r1) for the monomers is 4-ethyl (4.69) > 3-methyl (4.18) > 4-t-butyl (2.98) > 2-ethyl (2.52) > 4-butyl (2.47) > 4-methyl (1.86) > 4-i-butyl (0.94) > 2-methyl (0.87). Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200–500°C range with residue (3–8% wt), which then decomposed in the 500–800°C range. 相似文献
15.
Caitlin E. Karver Eric S. Molina Erin T. Economos Jonathan C. Fuentes Socrates M. Kaitson Samuel Kogan 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(2):101-105
Electrophilic trisubstituted ethylenes, halogen ring-substituted methyl 2-cyano-3-phenyl-2-propenoates, RPhCH=C(CN)CO2CH3 (where R is 3-Br-4-CH3O, 5-Br-2-CH3O, 2-F-5-CH3, 2-F-6-CH3, 4-F-3-CH3, 4-F-3-PhO, 2-F-5-I, 2-F-6-I, 2-F3C, 4-F3C) 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 analysis, IR, 1H and 13C-NMR. All the ethylenes were copolymerized with styrene (M1) 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. The order of relative reactivity (1/r 1) for the monomers is 2-F-5-CH3 (6.4) > 4-F-3-PhO (5.6) > 4-F3C (4.8) > 3-Br-4-CH3O (3.7) > 2-F-5-I (3.6) > 2-F3C (2.2) > 2-F-6-I (2.1) > 5-Br-2-CH3O (1.9) > 4-F-3-CH3 (1.8) > 2-F-6-CH3 (1.2). Relatively high 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 trisubstituted ethylene monomer unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200-500°C range with residue (2–21% wt), which then decomposed in the 500–800°C range. 相似文献
16.
Gregory B. Kharas Sara M. Rocus Marissa C. Locke William J. Macke Sarah S. Oh Nathanial A. Pagan 《高分子科学杂志,A辑:纯化学与应用化学》2016,53(8):465-469
Novel trisubstituted ethylenes, halogen ring-trisubstituted butyl 2-cyano-3-phenyl-2-propenoates, RPhCH ?C(CN)CO2C4H9 (where R is 3-bromo-4,5-dimethoxy, 5-bromo-2,4-dimethoxy, 2-bromo-3-hydroxy-4-methoxy, 3-chloro-2,6-difluoro, 4-chloro-2,6-difluoro, 2,3,5-trichloro, 2,3,6-trichloro, 2,4,5-trifluoro) 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 200–500°C range with residue (3–5% wt.), which then decomposed in the 500–800°C range. 相似文献
17.
G. B. Kharas Hemal Bhavsar Kylie S. Nordness Erin A. Pekovitch Megan E. Pyrz Eric R. Rice 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(6):407-411
Novel electrophilic trisubstituted ethylene monomers, halo ring-substituted 2-cyano-3-phenyl-2-propenamides, RPhCH ? C(CN)CONH2, where R is 2-bromo, 3-bromo, 2-fluoro, 3-fluoro, 2-iodo, 3-iodo, and 4-iodo were prepared and copolymerized with styrene. The monomers 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, 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. 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 (7-19 wt%), which then decomposed in the 500–800°C range. 相似文献
18.
Gregory B. Kharas Hui Feng Christopher Aranda Maya E. Navarro Stephanie Pacheco Quinn Pazderka 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(7):504-509
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
19.
Gregory B. Kharas Sonia E. Chavez Alex C. Mast Mark Krzeszowiec Stan Mazo 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(6):451-454
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
20.
Gregory B. Kharas Benjamin L. Hill Nga Y. Du Andrea S. Lorenz Nelly Fliman Amy M. Reznick 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(2):94-98
Electrophilic trisubstituted ethylenes, fluoro ring-substituted ethyl 2-cyano-1-oxo-3-phenyl-2-propenylcarbamates, RC6H3CH = C(CN)CONHCO2C2H5(where R is 4-F-3-CH3, 2-CF3, 4-CF3, 2,4-diF, 2,5-diF, 2,6-diF, 3,4-diF, and 3,5-diF), were prepared and copolymerized with styrene. The monomers were synthesized by the piperidine catalyzed Knoevenagel condensation of ring-substituted benzaldehydes and N-cyanoacetylurethane, 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 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 4-CF3 (5.4) > 2,6-diF (2.0) > 2,4-diF (1.7) > 2,5-diF (1.0) > 2-CF3 (0.8) > 3,4-diF (0.5) > 3,5-diF (0.4) > 4-F-3-CH3 (0.3). High T g of the copolymers in comparison with that of polystyrene indicates decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene structural unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in 270–420°C with residue (5–13% wt), which then decomposed in the 420–650°C range. 相似文献