乙酰化稻草/PE复合材料的力学性能

由于植物纤维是极性、亲水性材料,塑料是非极性、疏水性材料,两种材料的界面相容性差,因此,分别以天然稻草和乙酰化稻草为填充体,以聚乙烯为基体,通过共混和挤出制备了PE/稻草复合材料.研究共混条件对微观结构和拉伸性能的影响,结果表明:天然稻草/PE复合材料内部有大量气泡,存在应力缺陷,其拉伸性能较差;稻草经乙酰化,极性和吸水性降低,与基体PE的界面相容性得到很大改善.在稻草质量分数相同的情况下,改性稻草WPC的拉伸强度、断裂伸长率分别约是天然稻草WPC的1.5倍和2倍.

Mechanical Properties of Acetylated Rice Straw/PE Composite

The interface compatibility between plant fibres and plastics is poor because the former is polar and hydrophilic, while the latter is nonpolar and hydrophobic. So, WPCs(wood plastic composites), with PE as matrix, natural rice straw and acetylated rice straw as fillers, were prepared by blending and extrusion. The impact of blending conditions on the microstructure and tensile properties was studied. The results showed that the tensile properties of natural rice straw/PE composite were poor due to a large number of bubbles existed within the structure, which resulted in stress defects. After acetylation, the interface compatibility between rice straw and PE was improved remarkably because the polarity and hydrophilism of rice straw fibres were reduced. When the mass fractions of rice straw were the same in WPC, the tensile strength and the elongation at break of acetylated rice straw/PE composites were 1.5 and 2 times those of natural rice straw/PE composites, respectively.