Study on degradation and closed-loop recycling of wind power composite based on alcohol-alkali catalytic system

doi:10.19936/j.cnki.2096-8000.20260628.016

Abstract

Abstract: Epoxy resin-based composites are widely used in the wind energy industry. Due to the stable three-dimensional network structure formed after the crosslinking of epoxy resin, the recycling and utilization of a large number of discarded wind turbine blade composites have become a challenge. Against this backdrop, this study developed a catalyst system using an alcohol solution of potassium hydroxide, which enables the complete degradation of acid-anhydride-cured epoxy resin under mild reaction conditions of 100 ℃ for 8 hours. This method was applied to the degradation and recycling of pultruded plates. During the reaction, the ester bonds in the polymer were selectively cleaved, with the epoxy resin-based portion transformed into bisphenol A glycidyl ether, and the methyltetrahydrophthalic anhydride curing agent converted into carboxylate salts. Meanwhile, the glass fiber/carbon fiber was completely recovered. The degradation product, bisphenol A glycidyl ether, was used as an active component and reused in the pultruded plate resin formulation, maintaining high strength and modulus. The carboxylate salts were post-treated to convert into high-purity methyltetrahydrophthalic anhydride, which was reused as a curing agent in the pultruded epoxy resin formulation, and the mechanical properties of the pultruded plates reached the same level as commercially available products.

Key words: wind turbine blades, epoxy resin, pultruded plates, degradation, recycling

CLC Number:

TB332

YAO Yalin, XIAO Hongqing, YAN Chongchong, SHA Qiqi, SU Zhiqiang. Study on degradation and closed-loop recycling of wind power composite based on alcohol-alkali catalytic system[J]. COMPOSITES SCIENCE AND ENGINEERING, 2026, 0(6): 146-153.

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