2025 Volume 61 Issue 3 Pages 56-66
Benzoxazine resin is an excellent thermosetting resin that not only has excellent hardness, heat resistance, flame retardancy, and electrical insulation properties, but also does not require acidic or basic catalysts during the curing process. Therefore, its use is expanding in fields related to adhesion, as a material useful for applications such as semiconductor encapsulants, printed wiring boards, insulating paints, and various resin modifiers. In this study, oligomers containing benzoxazine rings in their side chains were synthesized by radical copolymerization of maleimidobenzoxazines and vinyl monomers, and their thermosetting behavior was clarified. Selecting styrene, isobutyl vinyl ether, and methyl acrylate as vinyl monomers, the radical copolymerization of maleimidobenzoxazines containing an allyl group or phenyl group as an N-substituent was carried out in dimethyl sulfoxide at 60℃. As a result, oligomers with molecular weights ranging from several hundred to thousand were isolated as solid products insoluble in methanol. The thermal and mechanical properties of the thermoset products obtained by heating the obtained oligomers in the temperature range of 140℃ to 180℃ were investigated in detail.
