Commercially important extrusion film casting (EFC) processes for manufacturing plastic films or sheets are hampered by several instabilities that severely limits their productivity. In this research we focussed on one important instability: the draw resonance that occurs during the EFC process mainly under extensional flow conditions. Draw resonance is the sustained periodic oscillations in the film dimensions, notably film width and thickness, when the process operates beyond a critical draw ratio (CDR). In this research our goal was to reduce this draw resonance instability by incorporating well dispersed nanoclay fillers in a base polymeric resin (such as a linear low density polyethylene – LLDPE) to determine how these nanocomposite (NC) formulations can prevent or reduce the draw resonance defect. EFC experiments were conducted on the base resin and on the NC formulations under non-isothermal conditions to determine the onset of the draw resonance experimentally. Conventional linear stability analysis was performed to determine the onset of the draw resonance defect numerically. Numerical predictions for the onset of draw resonance were in qualitative agreement with our experimental data. Our results showed that incorporating appropriate nanoclay concentrations in a base polymeric resin indeed enhanced the EFC process stability for those polymer formulations and thus can have important economic implications for processors.

制造塑料薄膜或片材的商业上重要的挤出薄膜浇铸（EFC）工艺受到严重限制其生产率的几种不稳定因素的困扰。在这项研究中，我们集中于一个重要的不稳定性：EFC过程中主要在拉伸流动条件下发生的拉力共振。拉伸共振是当工艺操作超出临界拉伸比（CDR）时，薄膜尺寸（尤其是薄膜宽度和厚度）的持续周期性振荡。在这项研究中，我们的目标是通过在基础聚合物树脂（例如线性低密度聚乙烯– LLDPE）中掺入分散良好的纳米粘土填料，以确定这些纳米复合材料（NC）配方如何预防或减少拉伸共振，从而降低这种拉伸共振的不稳定性。缺陷。在非等温条件下，对基础树脂和NC配方进行了EFC实验，以实验确定拉伸共振的开始。进行常规的线性稳定性分析，以数字方式确定拉伸共振缺陷的发生。拉伸共振发生的数值预测与我们的实验数据在质量上吻合。我们的结果表明，在基础聚合物树脂中掺入适当的纳米粘土浓度确实可以提高这些聚合物配方的EFC工艺稳定性，因此对加工者可能具有重要的经济意义。进行常规的线性稳定性分析，以数字方式确定拉伸共振缺陷的发生。拉伸共振发生的数值预测与我们的实验数据在质量上吻合。我们的结果表明，在基础聚合物树脂中掺入适当的纳米粘土浓度确实可以提高这些聚合物配方的EFC工艺稳定性，因此对加工商可能具有重要的经济意义。进行常规的线性稳定性分析，以数字方式确定拉伸共振缺陷的发生。拉伸共振发生的数值预测与我们的实验数据在质量上吻合。我们的结果表明，在基础聚合物树脂中掺入适当的纳米粘土浓度确实可以提高这些聚合物配方的EFC工艺稳定性，因此对加工商可能具有重要的经济意义。