Synthesis and preparation of biobased benzoxazine/bismaleimide copolymers: Thermal, mechanical and dielectric properties

• Published in: European polymer journal Vol. 179; p. 111524
• Main Authors: Sha, Xin-Long, Wang, Changze, Tan, Lu, Zhou, Jin, Liu, Zongtang, Fei, Zhenghao, Miao, Jia-Tao
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 05.10.2022; Elsevier BV
• Subjects: Benzoxazine; Benzoxazines; Biobased; Bismaleimide; Bismaleimides; Copolymerization; Copolymers; Data envelopment analysis; Dielectric properties; Flexural strength; Glass transition temperature; Low dielectric constant; Mechanical properties; Segments; Temperature; Thermal decomposition; Thermosetting resins; Benzoxazine; Low dielectric constant; Biobased; Bismaleimide
• ISSN: 0014-3057; 1873-1945
• DOI: 10.1016/j.eurpolymj.2022.111524

A low dielectric constant biobased benzoxazine/bismaleimide copolymer is developed with a green synthesis strategy. [Display omitted] •A unique benzoxazine monomers (E-dea) with active allyl terminations were synthesized using a green synthesis strategy.•Poly(E-dea/BMI) have outstanding thermal, mechanical and low dielectric performances.•The nature behind these attractive performances of poly(E-dea/BMI) was intensively investigated. Preparation of low dielectric thermosetting resins by green method is a challenging subject. Herein, unique bio-based benzoxazine monomer E-dea was prepared by a solvent-free method using eugenol as phenol source, and then E-dea and bismaleimide (BMI) were copolymerized to prepare poly(E-dea/BMI-0.86) and poly(E-dea/BMI-1). The comprehensive properties including thermal, mechanical and dielectric properties of the copolymers were studied. Notably, poly(E-dea/BMI-0.86) and poly(E-dea/BMI-1) exhibit low dielectric properties with dielectric constants of 2.85 and 2.79 at 1 MHz, respectively. Besides, the glass transition temperature (Tg), the initial thermal decomposition temperature (Tdi) and the flexural strength of poly(E-dea/BMI-0.86) and poly(E-dea/BMI-1) are 167 °C and 169 °C, 333 °C and 321 °C and 115 ± 3.5 MPa and 123 ± 4.9 MPa, respectively. The excellent comprehensive performance is attributed to the interaction between flexible and low dielectric decane segments and rigid oxazine and BMI segments.