For evaluation of the rheological and mechanical properties of highly filled wood plastic composites (WPCs), polypropylene/polyethylene (PP/PE) blends were grafted with maleic anhydride (MAH) to enhance the inte...For evaluation of the rheological and mechanical properties of highly filled wood plastic composites (WPCs), polypropylene/polyethylene (PP/PE) blends were grafted with maleic anhydride (MAH) to enhance the interfacial adhesion between wood fiber and matrix. WPCs were prepared from wood fiber up to 60 wt.% and modified PP/PE was blended by extrusion. The rheological properties were studied by using dynamic measurement. According to the strain sweep test, the linear viscoelastic region of composites in the melt was determined. The result showed that the storage modulus was independent of the strain at low strain region (〈0.1%). The frequency sweep resuits indicated that all composites exhibited shear thinning behavior, and both the storage modulus and complex viscosity of MAH modified composites were decreased comparing to those unmodified. Flexural properties and impact strength of the prepared WPCs were measured according to the relevant standard specifications. The flexural and impact strength of the manufactured composites significantly increased and reached a maximum when MAH dosage was 1.0 wt%, whereas the flexural modulus after an initial decreased, also increased with MAH dosage. The increase in mechanical properties indicated that the presence of anhydride groups enhanced the interracial adhesion between wood fiber and PP/PE blends.展开更多
目的以PE,PP为原料,接枝马来酸酐(MAH)后,与高岭土经双螺杆挤出机熔融共混挤出,制备PE-g-MAH/PP/高岭土复合材料。方法采用电子万能试验机分析复合材料的拉伸性能;采用电子悬臂冲击实验机分析材料的缺口冲击强度;采用水平垂直燃烧仪测...目的以PE,PP为原料,接枝马来酸酐(MAH)后,与高岭土经双螺杆挤出机熔融共混挤出,制备PE-g-MAH/PP/高岭土复合材料。方法采用电子万能试验机分析复合材料的拉伸性能;采用电子悬臂冲击实验机分析材料的缺口冲击强度;采用水平垂直燃烧仪测试分析复合材料的阻燃性;采用红外光谱仪分析复合材料的化学结构。结果含MAH质量分数为5%的PE与PP按质量比1∶1混合后,加入15%的高岭土,制备的PE-g-MAH/PP/高岭土复合材料拉伸强度、缺口冲击强度和断裂伸长率均为最佳,分别为10.925 MPa,40.6 k J/m2,89.5%;复合材料的阻燃性与高岭土加入量呈先快速增大后慢速降低趋势,加入量为15%时阻燃性最好;复合材料各组分间实现了化学键合。结论适量的高岭土提升了PE/PP复合材料的阻燃性,而MAH的加入改善了PE,PP和高岭土间的相容性。展开更多
文摘For evaluation of the rheological and mechanical properties of highly filled wood plastic composites (WPCs), polypropylene/polyethylene (PP/PE) blends were grafted with maleic anhydride (MAH) to enhance the interfacial adhesion between wood fiber and matrix. WPCs were prepared from wood fiber up to 60 wt.% and modified PP/PE was blended by extrusion. The rheological properties were studied by using dynamic measurement. According to the strain sweep test, the linear viscoelastic region of composites in the melt was determined. The result showed that the storage modulus was independent of the strain at low strain region (〈0.1%). The frequency sweep resuits indicated that all composites exhibited shear thinning behavior, and both the storage modulus and complex viscosity of MAH modified composites were decreased comparing to those unmodified. Flexural properties and impact strength of the prepared WPCs were measured according to the relevant standard specifications. The flexural and impact strength of the manufactured composites significantly increased and reached a maximum when MAH dosage was 1.0 wt%, whereas the flexural modulus after an initial decreased, also increased with MAH dosage. The increase in mechanical properties indicated that the presence of anhydride groups enhanced the interracial adhesion between wood fiber and PP/PE blends.
文摘目的以PE,PP为原料,接枝马来酸酐(MAH)后,与高岭土经双螺杆挤出机熔融共混挤出,制备PE-g-MAH/PP/高岭土复合材料。方法采用电子万能试验机分析复合材料的拉伸性能;采用电子悬臂冲击实验机分析材料的缺口冲击强度;采用水平垂直燃烧仪测试分析复合材料的阻燃性;采用红外光谱仪分析复合材料的化学结构。结果含MAH质量分数为5%的PE与PP按质量比1∶1混合后,加入15%的高岭土,制备的PE-g-MAH/PP/高岭土复合材料拉伸强度、缺口冲击强度和断裂伸长率均为最佳,分别为10.925 MPa,40.6 k J/m2,89.5%;复合材料的阻燃性与高岭土加入量呈先快速增大后慢速降低趋势,加入量为15%时阻燃性最好;复合材料各组分间实现了化学键合。结论适量的高岭土提升了PE/PP复合材料的阻燃性,而MAH的加入改善了PE,PP和高岭土间的相容性。