Preparation, polymerization and properties of an adamantyl‐based benzoxazine

• Published in: Polymer international 2023-05, Vol.72 (5), p.482-489
• Main Authors: Xia, Yiqing, Liu, Linze, Shi, Rui, Hao, Libo, Yan, Shuai, Wang, Lian, Gao, Chen, Zhang, Xuemei, Sheng, Yuping
• Format: Article
• Language: English
• Subjects: Acetanilide; adamantane; Aerospace materials; Alkylation; Aniline; benzoxazine; Benzoxazines; Curing; Diamines; Dielectric constant; Dielectric properties; Diphenyl methane; Dynamic mechanical analysis; Flammability; Fourier transforms; heat resistance; Infrared spectroscopy; Integrated circuits; Interlayers; low dielectric material; Magnetic resonance spectroscopy; NMR; NMR spectroscopy; Nuclear magnetic resonance; Thermal stability; Thermodynamic properties
• ISSN: 0959-8103; 1097-0126
• DOI: 10.1002/pi.6493

A novel adamantyl‐based benzoxazine (AD‐Bz) was successfully synthesized with 1,3‐bis(4‐aniline)‐adamantane (AD) derived from 1‐adamantanol and acetanilide through the Friedel–Crafts alkylation reaction. The chemical structure, curing behavior and curing kinetics of AD‐Bz were characterized by Fourier transform infrared spectroscopy, NMR spectroscopy (1H NMR and 13C NMR) and DSC, respectively. The results indicated that the activation energies (Ea) of AD‐Bz were 106.3 kJ mol−1 (Kissinger–Akahira–Sunose method) and 109.5 kJ mol−1 (Ozawa method), which are significantly lower than that of the benzoxazine derived from salicylaldehyde and 4,4′‐diamine diphenylmethane (P‐ddm). Furthermore, the thermal properties, dielectric properties and flammability properties of poly(AD‐Bz) were explored with dynamic mechanical analysis, an Agilent impedance analyzer and TGA. It was found that poly(AD‐Bz) exhibited higher heat‐resistant properties (Tg = 253.4 °C), higher thermal stability (Td,10% = 401 °C) and lower dielectric constant (εr = 3.16, 10 MHz) compared with poly(P‐ddm), favoring its application as a candidate for interlayer materials in ultra‐large‐scale integrated circuit and aerospace materials. © 2022 Society of Industrial Chemistry. In this paper, a novel adamantane‐containing benzoxazine (AD‐Bz) was obtained by introducing an adamantane structure into benzoxazine through molecular design. The resultant thermosets derived from adamantane‐containing benzoxazine (poly(AD‐Bz)) present high glass transition temperatures (Tg, 253 °C), excellent thermal stability (Td,10% = 401 °C) and lower dielectric constant (εr = 3.16, 10 MHz).