Novel Copolymers of Styrene. 16. Halogen Ring-Disubstituted Methyl 2-Cyano-3-Phenyl-2-Propenoates

• Published in: Journal of macromolecular science. Part A, Pure and applied chemistry Vol. 51; no. 10; pp. 751 - 755
• Main Authors: Kharas, Gregory B., Chavez, Sonia E., Browning, Harrison S., Sepe, Jennifer A., Romanelli, Mario E., Susnis, Melissa K., Choque-Gonzales, Gonzalo, Fuentes, Kevin N., Treneva, Ralitza A., Murphy, Casey M.
• Format: Journal Article
• Language: English
• Published: Colchester Taylor & Francis 03-10-2014
• Subjects: Applied sciences; Copolymerization; Exact sciences and technology; Organic polymers; Physicochemistry of polymers; Preparation, kinetics, thermodynamics, mechanism and catalysts; radical copolymerization; styrene copolymers; Trisubstituted ethylenes; Substituent effect; Fluorine containing copolymer; Preparation; Cyanoester; Chlorine containing copolymer; styrene copolymers; Radical copolymerization; Experimental study; Cinnamic derivative copolymer; Styrene copolymer; Trisubstituted ethylenes
• ISSN: 1060-1325; 1520-5738
• DOI: 10.1080/10601325.2014.937119

Electrophilic trisubstituted ethylenes, ring-disubstituted methyl 2-cyano-3-phenyl-2-propenoates, RPhCH˭C(CN)CO
2
CH
3
, 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,
1
H and
13
C-NMR. All the ethylenes were copolymerized with styrene (M
1
) 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,
1
H and
13
C-NMR. The order of relative reactivity (1/r
1
) for the monomers is 4-Cl-3-F (4.87) > 2,3-F
2
(4.49) > 3-Cl-4-F (3.50) > 3-Cl-2-F (2.96) > 2-Cl-5-NO
2
(2.02) > 2,5-Cl
2
(1.54) > 2-Cl-6-NO
2
(1.00) > 3,5-Cl
2
(0.41). 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 200-500ºC range with residue (1.5-34.5% wt), which then decomposed in the 500-800ºC range.