木材表面冷等离子体改性后的时效性研究

采用氮气和氧气2种冷离子体改性木材表面，利用水和二碘甲烷测试不同放置时间下木材表面接触角，根据YGGF方程计算表面自由能及其色散力和极性力。结果表明；经氧气和氮气冷等离子体改性后的木材表面自由能显著提高，1h后测得其表面自由能分别提高54．23％和54．41％；2种等离子体改性后表面自由能都随放置时间的延长逐渐降低，6～10d内活性降低迅速，14～21d后接近于改性前水平；氧气处理后木材表面接触角更小，处理效果更好。

Study on the Activation Time of Wood Surface Modified by Cold Plasma

The surface free energy, color diffusion and polarity power of the modified wood were calculated by means of the Young-Good-Girifalco-Fowkes expression after the wood surface was treated by N2 and O2 cold plasma, and the contacting angles were tested with water and di-iodomethane after having been placed for different time durations. The results showed that the surface free energy of the modified wood that was treated by N2, O2 cold plasma increased prominently, whose value was increased by 54.23% and 54.41% respectively after being treated for lh. But the surface free energy of the modified wood decreased gradually with the time going on, whose value declined prominently within 6 d - 10 d, and almost returned to the control in 14 d-21 d. The result also showed that contacting angles of the modified wood treated by O2 cold plasma were smaller than that of treated by N2 cold plasma, indicating the effect was better.