γ射线辐照处理竹材的动态黏弹性与温度变化的关系

Dynamic Viscoelastic Properties of γ Rays Treated Bamboo Strip in Different Temperatures

木质材料的动态黏弹性是指在交变的应力、应变作用下发生的滞后现象和力学损耗（徐有明,2006）,是影响材料加工利用的重要因素。研究表明：木材在不同的含水率下,或经干燥、压缩等不同处理后,其动态黏弹性均会发生改变（蒋佳荔等,

The dynamic viscoelastic properties of bamboo were tested by dynamic mechanics analyzer （DMA） , and the measurements were done in the temperature range of 40 ℃ to 300 ℃ at frequencies of 3 Hz. The results showed that ： with the increase of irradiation dose, the decrease of storage modulus with increasing temperature became more dramatically. The decrease extent of storage modulus was the lowest for nonirradiated bamboo Two mechanical relaxation processes were observed for all kinds of irradiated bamboo. The relaxation process in lower temperature range was due to glass transition of hemicellulose and login, while the relaxation process occurred in higher temperature range was based on glass transition of cellulose. The loss peak strength of cx relaxation process went up as the irradiation dose increase, while the loss peak strength of 13 relaxation process became go up first and then down, which was caused by the chemical reaction of the chief composition of bamboo.