Comb-shaped aromatic polyamide cross-linked by Diels-Alder chemistry: Towards recyclable and high-performance thermosets

Kaiju Luo, Jing Li, Guangyu Duan, Yan Wang, Junrong Yu, Jing Zhu, Zuming Hu

Index: 10.1016/j.polymer.2018.03.026

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Abstract

A new class of recyclable and high-performance thermosets from comb-shaped aromatic polyamides with pendent furan groups, which was prepared from a newly designed furan-containing diacid by high-temperature polycondensation in solution was reported. 1H nuclear magnetic resonance (1H NMR), fourier transform infrared spectroscope (FT-IR) and gel permeation chromatography demonstrated the chemical structure of target polyamides, while gelation test, 1H NMR and FT-IR characterizations revealed the capability of these polyamides to be reversibly crosslinked by bismaleimide via Diels-Alder reaction. The use of polyamides with high molecular weight and high content of regular pendent furan groups as precursor permitted the tailoring of mechanical properties of the resultant thermosets in a broad range by simply adjusting the ratio of furan to bismaleimide. In addition, the thermally reversible cross-linking by Diels-Alder reaction allowed the repeated recycling of cross-linked polyamide with reasonable recovery in mechanical properties.