CREPEC, Department of Chemical Engineering, École Polytechnique de Montréal, Montréal, QC H3C3A7, Canada.
Soft Matter. 2017 Apr 12;13(15):2844-2856. doi: 10.1039/c6sm02386j.
In this study it is shown that the three different intermediate phases in melt blended ternary PLA/PHBV/PBS, PLA/PBAT/PE and PLA/PE/PBAT systems all demonstrate partial wetting, but have very different wetting behaviors as a function of composition and annealing. The interfacial tension of the various components, their spreading coefficients and the contact angles of the confined partially wet droplets at the interface are examined in detail. A wetting transition from partially wet droplets to a complete layer at the interface is observed for both PHBV and PBAT by increasing the concentration and also by annealing. In contrast, in PLA/PE/PBAT, the partially wet droplets of PE at the interface of PLA/PBAT coalesce and grow in size, but remain partially wet even at a high PE concentration of 20% and after 30 min of quiescent annealing. The dewetting speed of the intermediate phase is found to be the principal factor controlling these wetting transitions. This work shows the significant potential for controlled wetting and structuring in ternary polymer systems.
在这项研究中表明，熔融共混三元 PLA/PHBV/PBS、PLA/PBAT/PE 和 PLA/PE/PBAT 体系中的三种不同中间相均表现出部分润湿，但作为组成和退火的函数具有非常不同的润湿行为。详细研究了各组分的界面张力、铺展系数以及受限部分润湿液滴在界面处的接触角。通过增加浓度和退火，观察到 PHBV 和 PBAT 的润湿从部分润湿液滴到界面处的完全层的转变。相比之下，在 PLA/PE/PBAT 中，PLA/PBAT 界面处的 PE 部分润湿液滴聚结并长大，但即使在 20%的高 PE 浓度和 30 分钟的静态退火后仍保持部分润湿。发现中间相的去湿速度是控制这些润湿转变的主要因素。这项工作表明，在三元聚合物体系中进行可控润湿和结构化具有重要的潜力。
