Preparation of heat-treated bamboo with nano-copper and its anti-mold performance
In this study,moso bamboo was vacuum immersed in a mixed solution of copper hydroxide,polyethylene glycol 200 and diethanolamine,and subjected to heat treatment for 4,6,and 8 h under 220 ℃.According to the principle of liquid-phase reduction,nano-copper was generated inside the heat-treated bamboo.The characterization of heat-treated bamboo was detected using the field emission scanning electron microscope(FE-SEM),Fourier infrared spectroscopy(FT-IR),X-ray diffractometer(XRD),and X-ray photoelectron spectroscopy(XPS).The results indicated that the copper element distributed in the bamboo and the content increased with increasing heat treatment time.XRD and XPS tests confirmed that the copper element was composed of nano-copper particles and a small amount of nano-copper oxide.The FT-IR test indicated that the substantial hemicellulose of bamboo was degraded,which resulted in a significant decrease in the number of hydrophilic groups.After being heat-treated,the mechanical properties of bamboo significantly decreased,while the moisture absorption was greatly reduced.However,the modulus of rupture(MOR)and modulus of elasticity(MOE)of the heat-treated bamboo with nano-copper particles still reached 92 MPa and 8.9 GPa,respectively,which was significantly higher than the heat-treated bamboo.At the same time,the contact angle of the heat-treated bamboo with nano-copper was up to 120°,and the moisture absorption rate was smaller than 5.0％,which was greatly enhanced compared to the heat-treated bamboo.Moreover,the heat-treated bamboo with nano-copper displayed superior anti-mold ability in the growth tests involving Aspergillus niger,Trichoderma viride,and Penicillium citri.The average infection values of all molds were below 0.1,and the anti-mold effects were up to 96％.Compared to natural bamboo and heat-treated bamboo,the anti-mold performance of the heat-treated bamboo with nano-copper was greatly improved.Therefore,the one-step method proposed in this study for preparing heat-treated bamboo with nano-copper was not only simple in process,but also excellent in performance.This will expand the application fields of bamboo and promote the efficient development of bamboo as a substitute for plastic.
国家科技期刊平台
NSTL
万方数据
