竹叶/HDPE复合材料的制备及性能

  目的  探讨竹叶和高密度聚乙烯（HDPE）制备竹叶基复合材料的可行性，以提高竹叶的附加值，实现竹叶废弃物的综合利用。  方法  以经乙醇提取后的毛竹Phyllostachys edulis叶为原料，HDPE为增强基体，添加适量助剂，采用热压成型与注塑成型2种工艺制备竹叶/HDPE复合材料。利用傅里叶变换红外光谱（FTIR）、X射线衍射仪（XRD）、扫描电镜（SEM）、热重分析仪（TGA）进行结构与性能的表征，探究不同成型工艺下不同竹叶质量分数对复合材料的性能影响。  结果  热分析结果表明:2种工艺制备的竹叶/HDPE复合材料热稳定性均随着竹叶质量分数的增加而提高。力学性能结果表明:随竹叶质量分数增加，注塑成型竹叶/HDPE复合材料拉伸强度逐渐降低，抗拉模量逐渐增大；弯曲强度先增大后减小，当竹叶质量分数为40%时，热压成型和注塑成型复合材料弯曲强度均达到最大，分别为28.72和30.20 MPa。随竹叶质量分数增加，2种工艺制备的复合材料弯曲模量逐渐增大，最大值分别为1 564.92和1 696.15 MPa；冲击强度逐渐减小。  结论  相比而言，热压成型竹叶/HDPE复合材料热力学性能更加稳定，是具有一定应用前景的、环境友好的新型材料。

Preparation and properties of bamboo leaf/HDPE composites

  Objective  The research aim is to improve add value of bamboo leaves.  Method  Novel composites were prepared from ethanol treated bamboo leaves(Phyllostachys edulis) by both hot press molding and injection molding, using high density polyethylene (HDPE) as reinforcing agent and appropriate amount of additives. The structure and properties of the composite were characterized by fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA), and the effects of different contents of bamboo leaves on the properties of composites by the two different molding processes were investigated.  Result  Thermal analysis results showed that the thermal stability of the composites prepared by the two different molding processes increased with the increase of the relative content of bamboo leaves. Mechanical property results indicated that the tensile modulus of composite prepared by injection molding also increased with the increase of the content of bamboo leaves, while the tensile strength decreased. When the content of bamboo leaves increased, the bending strength of the composite increased first and then decreased. The maximum bending strength of the composites obtained by hot press molding and injection molding reached 28.72 and 30.20 MPa when the bamboo leaf content was 40%. The bending modulus of composites obtained by hot press molding and injection molding increased with the increase of the content of bamboo leaves, and the maximums reached 1 564.92 and 1 696.15 MPa, respectively. The impact strength gradually decreased with the increase of the bamboo leaf content.  Conclusion  In contrast, the hot pressed bamboo leaf/HDPE composite had more stable thermal properties, and could be a new environmentally friendly material.