Frontiers in Chemistry (Apr 2022)

Metal Ion-Catalyzed Low-Temperature Curing of Urushiol-Based Polybenzoxazine

  • Wen Yang,
  • Yaofeng Xie,
  • Jipeng Chen,
  • Chunmei Huang,
  • Yanlian Xu,
  • Yucai Lin,
  • Yucai Lin,
  • Yucai Lin

DOI
https://doi.org/10.3389/fchem.2022.879605
Journal volume & issue
Vol. 10

Abstract

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In this work, urushiol-based polybenzoxazine is cured by the Lewis acid (FeCl3, AlCl3, and CuCl2) at low temperature instead of high thermal curing temperature. The effect of the Lewis acid on structures and properties of the polymers is revealed. The relating urushiol-based benzoxazine monomer (BZ) was synthesized by natural urushiol, formaldehyde, and n-octylamine. The monomer was reacted with the Lewis acid with a molar ratio of 6:1 (Nmonomer: NMetal) at 80°C to obtain films that can be cured at room temperature. The chemical structures of benzoxazine monomers were identified by Fourier-transform infrared spectroscopy (FTIR) and 1H nuclear magnetic resonance spectroscopy (1H-NMR). The interaction between the metal ion and the polymers is revealed by X-ray photoelectron spectroscopy (XPS) and attenuated total reflectance-FTIR (ATR-FTIR). The effect of the Lewis acid on the mechanical properties, wettability, and thermal stability was investigated. The results show that the benzoxazine cured by Cu2+ has a better performance than that cured by Al3+ and Fe3+.

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