Improvement of softening treatment technology of bamboo

In order to improve the efficiency of softening bamboo block when manufacturing bamboo veneer, chemistry reagents such as NaHCO3 are often adopted during bamboo softening treatment. But the results of Fourier transform infrared spectroscopy (FTIR) showed that the band intensity at 1,733 cm(-1), assigned to C=O stretching vibration in xylan, was reduced in the spectrum of softening-treated bamboo with NaHCO3 compared with that of not softening-treated bamboo and softening treatment of bamboo without NaHCO3. That is to say, that the hemicellulose of bamboo was destroyed after softening treatment with NaHCO3, which meant that softening treatment of bamboo with NaHCO3, is not a perfect softening treatment method. Thus, in this paper a softening technology at 120 degrees C for 30 min in a closed container was adopted. The results of FTIR show that there was almost no difference in FTIR spectra between no softening treatment of bamboo and softening treatment of bamboo at 120 degrees C for 30 min, which meant that softening treatment at 120 degrees C for 30 min had no effect on the composition of bamboo. The results of dynamic mechanical analysis (DMA) show that T (g) of not softening-treated bamboo was 120 degrees C, while T-g of softening-treated bamboo at 120 degrees C for 30 min was 88 degrees C. T-g of softening-treated bamboo at 120 degrees C for 30 min decreased by 26.7% compared with that of not softening-treated bamboo. The results of hardness show that the hardness of bamboo strip after a softening treatment for 30 min at 120 degrees C decreased by 42.0-54.6% compared with that of not softening-treated bamboo. The results of hardness and DMA show that the effect of softening treatment of bamboo at 120 degrees C for 30 min was resultful.