Polyethylene (PE)/silica polymer nanocomposites (PNCs) were investigated mainly using rheological measurements. Various PEs [linear low-density polyethylene (LLDPE), high-density polyethylene (HDPE), and low-density polyethylene (LDPE)] were selected as polymer matrices, and two comparable particulate silicas were utilized as favorable (hydrophobic, R202) or unfavorable (hydrophilic, A90) fillers. Small amplitude oscillatory shear (SAOS), large amplitude oscillatory shear (LAOS), elongational rheometry, tensile tests, and TEM were adopted to characterize PE/silica PNCs. LDPE/silica nanocomposites showed the best filler dispersion in TEM images but were the poorest in terms of rheological property enhancement. Linear viscoelasticity as determined by SAOS testing was discordant with their morphology. However, nonlinear viscoelasticity as determined by FT-rheology in LAOS testing adequately determined dispersion states. Elongational viscosity revealed LDPE/silica PNCs show strain-hardening behavior, which resulted in intense mixing conditions and best compatibilization on LDPE/silica PNCs. To quantify the strain-hardening effect, strain hardening coefficients (SHCs) were calculated for LDPE/silica PNCs and found to decrease with increasing silica concentration. In addition, tensile testing showed mechanical properties deteriorated with silica content.

聚乙烯（PE）/二氧化硅聚合物纳米复合材料（PNC）的研究主要是使用流变学方法。选择了各种PE [线性低密度聚乙烯（LLDPE），高密度聚乙烯（HDPE）和低密度聚乙烯（LDPE）]作为聚合物基质，并使用了两种相当的颗粒二氧化硅作为有利的（疏水性，R202）或不利的（亲水性，A90）填料。PE /二氧化硅PNC的特性采用小振幅振荡剪切（SAOS），大振幅振荡剪切（LAOS），伸长流变学，拉伸试验和TEM。LDPE /二氧化硅纳米复合材料在TEM图像中显示出最佳的填料分散性，但在流变性能增强方面表现最差。通过SAOS测试确定的线性粘弹性与其形貌不一致。然而，FT-流变学在LAOS测试中确定的非线性粘弹性足以确定分散状态。拉伸粘度表明LDPE /二氧化硅PNC表现出应变硬化行为，这导致了剧烈的混合条件和LDPE /二氧化硅PNC的最佳相容性。为了量化应变硬化效果，计算了LDPE /二氧化硅PNC的应变硬化系数（SHC），发现其随二氧化硅浓度的增加而降低。另外，拉伸试验表明机械性能随二氧化硅含量降低。计算了LDPE /二氧化硅PNC的应变硬化系数（SHC），发现其随二氧化硅浓度的增加而降低。另外，拉伸试验表明机械性能随二氧化硅含量降低。计算了LDPE /二氧化硅PNC的应变硬化系数（SHC），发现其随二氧化硅浓度的增加而降低。另外，拉伸试验表明机械性能随二氧化硅含量降低。