赤桉木材微纳米粒子溶出规律的研究

采用单因素试验法，分析赤桉溶出粒子的特征，探索赤桉木材纳米粒子在索氏抽提、超声波抽提、冷冻抽提、激光等离子抽提中的溶出规律。结果表明：（1）回归曲线显示，在索氏抽提过程中，抽出量随赤桉木片抽提时间延长而增大；（2）在索氏苯/醇抽提过程中，以体积分数为评价指标时，溶出的纳米粒子直径主要集中在37.8～106nm,60.27%；以数量分数为评价指标时，溶出的纳米粒子直径主要集中在28.2～91.3nm,83.68%； 4150～5560、4150～5560nm、1110～6440nm的粒子数量极少而无法测试，其体积分数仅分别为0.3％、0.3％、2.6％，但足以对木材渗透产生屏障、对制浆产生树脂障碍；（3）超声波抽提过程中，粒径在28.2～78.8 nm之间的纳米粒子的体积分数为80.1％，粒径在24.4～50.7 nm之间的粒子数占89.0％，而粒径在190～396 nm之间的粒子体积占15.2％，且数量极少；冷冻抽提过程中，粒径在18.2～32.7 nm之间的纳米粒子的体积分数为89.0％，粒径在18.2～28.2 nm之间的粒子数占88.6％，而粒径在220～531 nm之间的粒子体积占4.7％，且数量极少；激光等离子抽提过程中，粒径在11.7～18.2 nm之间的纳米粒子的体积分数为92.3％，粒径在11.7～18.2 nm之间的粒子数占96.5％，而粒径在220～396 nm之间的粒子体积占1.6％，且数量极少。由此可见，超声波、冷冻预处理、激光等离子在抽提中均能降低赤桉木材微纳米粒子的集聚程度，而且还能提高微纳米粒子的溶出量，其中激光等离子抽提效果最好。

State Key of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640

In order to overcome the negative effects, the extractives of the fresh E. camaldulensis shavings, which were obtained by using the sorbitic-, freezing-, laser plasma- and supersonic-extracting approaches, were analyzed by ZETA and SIZER to find out the leaching rule of micro and nano particles in E. camaldulensis wood. The results are as follows: (1) During the sorbitic-extracting process, the extracted quantity of micro and nano particles increases with the extracting time. Based on the evaluating indicator of the volume fraction and the mass fraction, 60.27% and 83.68% of the particles are mainly distributed in the range of 37.8-106 nm and 28.2-91.3 nm in diameter, respectively, despite volume fraction 0.3%，0.3% and 2.6% of the particles with the diameter of 4150-5560 nm, 4150-5560 nm and 1110-6440 nm, respectively, it is enough for these particles to be able to result in the obstructive effects on the permeability and the pulping. (2) During the supersonic-extracting process, the particles with the diameter of 28.2-78.8 nm and 24.4-50.7 nm occupy 80.1% and 89.0%, respectively, while the volume of 190~396 nm particles is 15.2%, but its number was very less. During the freezing-extracting process, the particles with the diameter of 18.2-32.7 nm and 18.2-28.2 nm occupy 89.0% and 88.6%, respectively, while the volume of 220-531 nm particles is 4.7%, but its number was very less. During the laser plasma- extracting process, the particles with the diameter of 11.7-18.2 nm and 11.7-18.2 nm occupy 92.3% and 96.5%, respectively, while the volume of 220-396 nm particles is 1.6%, but its number was very less. Therefore, freezing-, laser plasma- and supersonic-extracting approaches all could not only lower the grouping number of leached micro and nano particles from E. camaldulensis, but also enhance extraction mass.