Novel copolymers of styrene. 5. Alkyl and alkoxy ring-disubstituted propyl 2-cyano-3-phenyl-2-propenoates

ABSTRACT

Novel trisubstituted ethylenes, alkyl and alkoxy ring-disubstituted propyl 2-cyano-3-phenyl-2-propenoates, RPhCH˭C(CN)CO₂C₃H₇ (where R is 2,3-dimethyl, 2,5-dimethyl, 2,6-dimethyl, 3,4-dimethyl, 2,3-dimethoxy, 2,4-dimethoxy, 2,5-dimethoxy, 2,6-dimethoxy 3,4-dimethoxy, 3,5-dimethoxy) 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 (0.6–5.0% wt.), which then decomposed in the 500–800°C range.

KEYWORDS:

• Trisubstituted ethylenes
• radical copolymerization
• styrene copolymers

Funding

The authors are grateful to acknowledge that the project was partly supported by the Coatings Industry Education Fund (CIEF) and Chicago Society of Coating Technology (CSCT). Wellington M.B. Barros was partially supported by CSCT funds, the CIEF Joseph A. Vasta Scholarship, and by Brazil Scientific Mobility Program.