This study concerns the synthesis and characterization of maleimide-based monomers and polymers. N-phenylmaleimide, 4'-N-maleimido-2,3'- dimethylazobenzene and N-p-chlorophenylmaleimide monomers were formed by imidizing maleic anhydride with aniline, 4'-amino-2,3'-dimethylazobenzene and p-chloroaniline, respectively. But N-nitrophenylmaleimide monomer was produced from the nitration of N-phenylmaleimide monomer. The two homopolymers, poly-(N-p-chlorophenylmaleimide) and poly-(Nnitrophenylmaleimide), were synthesized by solution polymerization in toluene solvent. Poly-(Styrene-co-N-phenylmaleimide) and poly-(Styrene-co-4'-Nmaleimido- 2,3'-dimethylazobenzene), each with compositions of [50:50] and [92:8], were produced by imidizing maleic anhydride constructing commercial poly-(Styrene-co-maleic anhydride); [50:50] and [92:8]. Styrene and Nphenylmaleimide monomers were copolymerized in both solution and emulsion to form poly-(Styrene-co-N-phenylmaleimide). Likewise, styrene and 4'-Nmaleimido- 2,3'-dimethylazobenzene were copolymerized in both solution and emulsion to form poly-(Styrene-co-4'-N-maleimido-2,3'-dimethylazobenzene). In all, four maleimide monomers, two maleimide homopolymers, and eight maleimide copolymers were synthesized in this study. Fourier Transform Infrared Spectroscopy, Thermogravimetric Analysis and Differential Scanning Calorimetry techniques were utilized to carry out qualitative and quantitative analyses. The yields of the four monomers were not as high as expected, since toluene was not as good a solvent as either xylene or ethyl ether. However, the purities of the four monomers were considered to be very high. In addition, it is seen that the nitro group was a stronger electron-withdrawing group and led to a less thermally stable polymer compared to the chloro group. Based on the FTIR spectra of these copolymers, the following observations were made: (1) the formation of N-phenylmaleimide products from the imidization of maleic anhydride was more complete than the 4'-N-maleimido- 2,3'-dimethylazobenzene products, (2) the imidization of maleic anhydride was complete for the [92:8] copolymers, but incomplete for the [50:50] copolymers, (3) polymerization reactions including both emulsion and solution polymerizations were preferred over imidization reaction, and (4) solution polymerization was more favorable in the incorporation of imide than emulsion polymerization. From the analogy of TGA and DSC characteristics, the [50:50] and [92:8] polymers were alternating and random copolymers, respectively. Polymers synthesized by emulsion and solution polymerizations were random copolymers. The emulsion polymerized materials decomposed at higher temperatures than the solution polymerized materials. Most of the copolymer products were amorphous copolymers as no crystallization or melting behavior was observed on their DSC thermograms.
Library of Congress Subject Headings
Polymers; Polymerization; Maleic anhydride
Department, Program, or Center
School of Chemistry and Materials Science (COS)
Chen, Hua-Chin, "Synthesis and characterization of maleimide-based polymers" (1991). Thesis. Rochester Institute of Technology. Accessed from
RIT – Main Campus