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采用动态热机械分析(DMTA)测试毛竹材的储能模量(E′)和损耗模量(E″),分析在不同初含水率、笔壁径向部位、竹龄及距毛竹基部高度下毛竹材的储能模量和损耗模量及玻璃化转变温度(Tg)。结果表明:1毛竹材储能模量随着温度的升高呈逐渐减小的趋势,损耗模量随着温度的变化出现两个峰,当温度达到玻璃化转变温度时达到第1个峰值。2储能模量和损耗模量受初含水率的影响较大,随着含水率的增加呈相对减小的趋势;在竹壁径向上,储能模量和损耗模量由内而外依次增大;在同一温度下,毛竹材的储能模量和损耗模量具有随毛竹高度的增加而降低的趋势;不同竹龄毛竹材的储能模量和损耗模量略有差别,基本上随竹龄的增大而增大。3毛竹材Tg随含水率的增加而降低,在绝干状态时Tg为217~223℃;含水率为15%到饱水状态时,Tg在113~134℃之间;沿竹壁径向的竹青、竹肉和竹黄的Tg略有差别,30%含水率时的Tg在123~135℃之间;不同竹龄毛竹材的Tg并无较大差异,在120~123℃之间;不同高度的毛竹材Tg也无显著差异,在123~126℃之间。研究表明,在毛竹材的实际生产中可通过增加毛竹材周边温度和含水率以增加其塑性,使竹材的竹龄和高度选择更加宽泛。
The storage modulus (E ’) and loss modulus (E ") of the bamboo were tested by dynamic thermomechanical analysis (DMTA). The effects of different initial moisture content, radial position of pen wall, bamboo age and height of bamboo base The storage modulus, loss modulus and glass transition temperature (Tg) of Moso bamboo showed that the storage modulus of Moso bamboo decreased with the increase of temperature, and the loss modulus increased with the increase of temperature When the temperature reached the glass transition temperature, the first peak was reached.2 The storage modulus and loss modulus were greatly influenced by the initial moisture content, and decreased with the increase of the moisture content At the same temperature, the storage modulus and loss modulus of Phyllostachys pubescens tended to decrease with the height of Phyllostachys pubescens. At the same temperature, the storage modulus and the loss modulus increased from the inside to the outside. The storage modulus and loss modulus of bamboo with different bamboo ages are slightly different, which basically increase with the increase of bamboo age.3 The Tg of bamboo with bamboo decreases with the increase of water content, Tg is 217 ~ 223 ℃; when the moisture content is 15% to saturated water, the Tg is between 113 and 134 ℃; bamboo green, bamboo and bamboo along the radial direction of the bamboo wall Tg slightly different, 30% moisture content when the Tg between 123 ~ 135 ℃; different bamboo age bamboo has no significant difference in Tg, between 120 ~ 123 ℃; different height of the bamboo has no Tg Significant difference between 123 ~ 126 ℃ .Studies show that in the actual production of bamboo can be increased by bamboo hair around the temperature and moisture content to increase their plasticity, so that bamboo bamboo age and a high degree of choice is more broad.