木粉表面自由能和表面极性对木塑复合材料界面的影响

Influence of Woodflour Surface Energy and Its Polar Part on Interface of PE-HD/Woodflour Composites

通过毛细管上升法测定了水曲柳木粉(MWF)、落叶松木粉(MWF)的表面接触角,依据Washburn方程和Owens法,求解水曲柳木粉和落叶松木粉的表面自由能及其极性和非极性分量。结果表明,水曲柳木粉的表面自由能为36.06mN/m,体现分子色散力的非极性分量为32.54 mN/m;而落叶松木粉的表面自由能为20.17 mN/m,其非极性分量为10.41 mN/m。因此,与同种塑料复合,水曲柳木粉有比落叶松木粉更好的界面粘接性。扫描电子显微镜进一步证实了水曲柳木粉在基体中的分散性好于落叶松木粉。

The contact angles of manchurian ash woodflour（MWF） and larch woodflour （LWF） were tested by capillary rise methods. Based on Washburn equation and methods suggested by Owens, the surface free energies of MWF and LWF were calculated. Results demonstrate that the surface free energy and its non polar part of MWF is 36.06 mN/m and 32.54 mN/m; while LWF is 20.17 mN/m and 10.41 mN/m, respectively. Then we can concluded that when combined with the same plastics, the interfacial adhesion between MWF and matrix is better than that of LWF. The observations were well supported by the scanning electron mieroscope（SEM）.