Anti-mold and hydrophobicity of cutinized bamboo prepared via different annealing processes

Abstract

To improve the hydrophobicity and anti-mold properties of bamboo, cutinized bamboo was prepared by impregnating a mixture of food-grade carnauba wax and paraffin at annealing temperatures of 78 °C, 80 °C, and 83 °C. The thermal properties and microstructures of the wax films were analyzed to understand the mechanism of wax interface phase. The contact angle, water absorption rate, dimensional stability, and microstructure of the cutinized bamboo were investigated. The results showed that phase separation occurred in the mixed wax and that the microstructure of the mixed wax films was reconstructed after annealing treatment. The thickness of the cutinized coating varied with the annealing temperature. The initial contact angle on the outer layer surface of cutinized bamboo reached 110.73°, and the surface energy was reduced by 53.6% at an annealing temperature of 83 °C. The water absorption and dimensional stability of the cutinized bamboo improved significantly. In addition, bamboo toothbrush handles modified at annealing temperature of 80 °C demonstrated good anti-mold. The annealing process of wax treatment is expected to benefit bamboo product protection. • Cutinized bamboo was prepared with mixed wax and annealed under different temperature. • The microstructure of mixed wax coating was reconstructed with phase separation after annealing. • The hydrophobicity of cutinized bamboo increased with annealing temperature. • Better hydrophobicity and anti-mildew were obtained after annealing treatment.