玉米秸秆粉/HDPE复合材料表面特性的研究

Study on the surface characteristics of corn stover fibers/HDPE wood-plastic composites

采用毛细管上升法测定了不同探测液在未改性玉米秸秆粉和4%硅烷偶联剂改性玉米秸秆粉表面的接触角,依据Washburn方程,采用Owens-wendt-Kaelble途径,计算了未改性玉米秸秆粉和改性玉米秸秆粉的表面自由能及其分量。结果表明:未改性的玉米秸秆粉的表面自由能为28.88mJ/m2,体现分子极性的极性分量为22.20mJ/m2;而改性玉米秸秆粉的表面自由能为35.69mJ/m2,体现分子极性的极性分量为3.51mJ/m2。因此,在与热塑性塑料复合时,改性玉米秸秆粉有更好的界面相容性。玉米秸秆粉/HDPE复合材料的弯曲断面形貌进一步证实了改性玉米秸秆粉有更好的界面相容性。

The contact angles of three probe liquid against unmodified and modified corn stover fibers were tested by capillary rise method,based on Washburn equation and the method of Owens-wendt-Kaelble,the surface free energy and its components of unmodified and modified corn stover fibers were calculated.The results showed that the surface free energy of unmodified corn stover fibers was 28.88mJ/m2 and its polar component was 22.20 mJ/m2,the surface free energy of modified corn stover fibers was 35.69mJ/m2 and its polar component is 3.51mJ/m2.Therefore,modified corn stover fibers had better interfacial compatibility with thermoplastics,which was also confirmed by the fractured surface morphology of corn stover fibers/HDPE wood-plastic composites.