Simultaneous modification and solidification of bamboo Fiber/Epoxy composites

Bamboo fiber (BF) composite is a sustainable and environmentally friendly material. However, the traditional preparation process requires multiple modification processes, leading to changes in fiber properties, and often results in strength loss and energy waste. To address these issues, we report a novel tetrahydromethyl-1,3-isobenzofurandione epoxy system (MeTHPA-EP) that can simultaneously modify BF and solidify the matrix, resulting in a more efficient and sustainable composite material. In the BF/MeTHPA-EP forming process, BF acts as an "accelerator," promoting the curing reaction and advancing the exothermic peak of the matrix by 10℃. Meanwhile, MeTHPA acts as a "bridge," reducing the wettability of BF by 35–50% and decreasing the porosity to 1.02%. The combined effect of these two factors significantly strengthens BF as reinforcement, increasing matrix strength by 5.77 times and modulus by 5.82 times, exhibiting apparent ductile bulk failure. Furthermore, we conducted a comparison with the traditional isophorone diamine curing agent, verifying the superiority of the MeTHPA-EP system in reducing voids and enhancing interfacial stability. Our research expands the applicability of bamboo fiber as a reinforcing material, providing a cost-effective, environmentally friendly, and effective method for producing high-performance bamboo fiber composites.