Flexible transparent wood enabled by epoxy resin and ethylene glycol diglycidyl ether

Abstract

Transparent wood has potential application in intelligent building, solar cell, electronics, and other advanced materials, while its single functionability hinders its further development. Flexible transparent wood (FTW) was prepared by alkaline pretreatment and bleaching treatment of paulownia wood followed by impregnation of epoxy resin and ethylene glycol diglycidyl ether (EDGE). The effect of delignification degree on the optical and mechanical properties of FTW was studied, and the influence of the epoxy/EDGE ratio on the flexibility and mechanical properties of FTW was also investigated. The results showed that higher delignification degree resulted in higher transmittance of FTW. More EDGE addition led to better flexibility of FTW, while overmuch addition of EDGE will reduce the mechanical properties. The optimal FTW sample resulted in a high transmittance of 89% and an ultrahigh haze value of 97% with outstanding flexibility and excellent mechanical properties. The investigation of FTW broadens the research field of transparent wood, and provides great possibility for its application in flexible wearable devices and flexible materials.

Keywords

Transparent wood / Epoxy resin / Ethylene glycol diglycidyl ether / Flexibility

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