Effect of Different Treatment on Softening of Bamboo Culm

Experiments were conducted on softening of Phyllostachys heterocycla cv. pubescens culm with pretreatment of dipping in 6% ammonia, and followed by 10%, 20%, 30%, 40% and 50% urea at 95℃ for 4 hours. The result demonstrated that cracks of flattened samples decreased with increase of urea concentration. It had no evident influence of internode on cracks when urea concentration was low, but when concentration increased, cracks of flattened samples without internode were fewer than that with internode. Radius of curvature had positive relation with concentration of urea. It had no evident influence of internode on radius of curvature when urea concentration was low, but when concentration increased, radius of curvature of flattened samples without internode had higher variation. Analysis by FTIR and XRD showed that softening properties of bamboo improved with higher concentrations of urea, because of the number of surface hydroxyl（-OH）and crystallinity of the samples increased gradually, even topped to 59.91%.