挤出口模结构对微孔木塑复合材料片材性能的影响

研究了不同的挤出口模结构对聚丙烯和聚乙烯基微孔木塑复合材料片材拉伸性能、密度和孔隙率的影响.结果表明,改变口模结构获得较大熔体压力降或压力降梯度时,木塑复合材料的拉伸强度、断裂伸长率较高,密度较小,孔隙率较高;压力变化为正向梯度变化时,木塑复合材料的拉伸强度较高,密度较小,孔隙率较高.

EFFECTS OF EXTRUSION DIE STRUCTURE ON PROPERTIES OF MICROCELLULAR WOOD-PLASTIC SHEET

Microcellular wood-plastic sheets were prepared by blending polyethylene or polypropylene with wood flour. The effects of extrusion die structure on tensile property, density and porosity of microcellular wood plastic sheet were studied. The results showed that the material with high tensile strength and elongation at break, low density and high porosity was prepared under the conditions of large melt pressure drop or pressure grads by changing extrusion die structure. The material with high tensile strength, low density and high porosity was prepared by high positive pressure grads.