Hah Jinho, Sulkis Michael, Kang Minsoo, Sun Zhijian, Kim Jihoon, Moon Kyoung-Sik, Reese Matthew O, Wong Ching Ping
School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States.
George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States.
ACS Appl Mater Interfaces. 2021 Jan 13;13(1):1682-1692. doi: 10.1021/acsami.0c13805. Epub 2020 Dec 30.
For many flexible electronic and photonic devices, moisture stability is one of the most important factors that affects its short- and long-term performance. To maintain the performance, the device should be packaged in such a way that it hermetically blocks moisture from the device; however, in practice, it is rather difficult to achieve. The more practical solution is to impede the moisture ingress to the device. In optoelectronic devices that will be outdoors like solar cells, the interfacial adhesion strength between the encapsulant layer (adhesive) and a moisture barrier layer is also a critical parameter. This paper presents surface modifications of poly(ethylene terephthalate) (PET) carrier films, one of the layers in the trilayer barrier film that directly adheres to an encapsulant, using chemical, UV/ozone, and both treatments to improve adhesion with the thermoset encapsulant polymer material. Whereas previous studies also utilized treatment methods to increase the wettability characteristics, in this paper, we not only present the results of the adhesion strength upon various techniques to achieve good adhesion but also screen their behavior upon exposure to a damp-heat (60 °C, 90% RH) environment. We found that the combined treatment method increases the adhesion by up to 12.1-fold and demonstrates up to a 200% increase in adhesion strength even upon our severe damp-heat environmental condition.
对于许多柔性电子和光子器件而言，湿度稳定性是影响其短期和长期性能的最重要因素之一。为保持器件性能，应采用能将湿气与器件完全阻隔的方式对其进行封装；然而，在实际中这很难实现。更切实可行的解决办法是阻止湿气进入器件。在诸如太阳能电池这类将用于户外的光电器件中，密封剂层（粘合剂）与防潮层之间的界面粘合强度也是一个关键参数。本文介绍了对聚对苯二甲酸乙二酯（PET）载体薄膜（三层阻隔膜中直接与密封剂粘合的一层）进行表面改性的方法，采用化学处理、紫外线/臭氧处理以及两者结合的处理方式，以提高其与热固性密封剂聚合物材料的粘合性。尽管先前的研究也采用处理方法来增强润湿性，但在本文中，我们不仅展示了通过各种技术实现良好粘合时的粘合强度结果，还筛选了它们在湿热（60°C，90%相对湿度）环境下的表现。我们发现，组合处理方法可使粘合性提高多达12.1倍，并且即使在我们设定的严苛湿热环境条件下，粘合强度也能提高多达200%。
