Synthesis and characterization of N‐acryloylcarbazole/methyl methacrylate copolymers

Abstract Copolymers of N ‐acryloylcarbazole (A) and methyl methacrylate (M) were synthesized in different in‐feed ratios. The composition of the copolymer was determined by the help of 1 H NMR spectrum. The comonomer reactivity ratios determined by Kelen‐Tudos (KT) and nonlinear error‐in‐variables methods were r A = 1.12 ± 0.16, r M = 0.94 ± 0.14, and r A = 1.05, r M = 0.90, respectively. Complete spectral assignments of the 1 H and 13 C 1 H NMR spectra of the copolymers were done by the help of distortionless enhancement by polarization transfer (DEPT) and two‐dimensional NMR techniques, such as heteronuclear single quantum coherence (HSQC), total correlation spectroscopy (TOCSY), and heteronuclear multiple bond correlation (HMBC). The methine, α‐methyl, and carbonyl carbon resonances were found to be sequence sensitive. The signals obtained were broad because of the restricted rotation of bulky carbazole group and the quadrupolar effect of nitrogen present in carbazole moiety. Glass transition temperatures ( T g ) were determined by differential scanning calorimetry and were found to be characteristic of copolymer composition. As the N ‐acryloylcarbazole content increases, the T g increases from 378.3 K for poly(methyl methacrylate) to 430.4 K for poly( N ‐acryloylcarbazole). Variation in T g with the copolymer composition were found to be in good agreement with theoretical values obtained from Johnston and Barton equations. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2667–2676, 2006