基于层状硅酸镁锂纳米片体相增强聚甲基丙烯酸 甲酯薄膜的水汽阻隔性能

To address the loss of flexibility and increased risk of side penetration in commercially applied inorganic/organic composite encapsulation films—issues often resulting from overly thick organic layers， this study investigates strategies for synergistically optimizing the barrier properties and interlayer adhesion of thinned organic layers. We constructed a thinned “sandwich-structured” composite film by incorporating synthesized lithium magnesium silicate （Laponite）nanosheets， both pristine and modified with cetyltrimethylammonium chloride（CTAC）， into a polymethyl methacrylate（PMMA）matrix， which was then laminated with silicon nitride（SiNx ） layers. The results demonstrate that the incorporated nanosheets significantly enhance the water vapor barrier performance by creating a tortuous diffusion path. Compared to the pristine Laponite system， the CTAC-modified nanosheets， owing to their hydrophobic surface and superior dispersion within the PMMA matrix， led to a remarkable improvement in the overall performance of the CTAC-Laponite-PMMA composite. The resulting film exhibited an ultra-low surface roughness of 0. 312 nm， ensuring excellent interfacial adhesion with the adjacent inorganic layers. Consequently， the water vapor transmission rate（WVTR） of the entire sandwich structure was further reduced to 5. 90× 10−5 g/（m2 ·day）. This work demonstrates a novel approach to co-optimizing barrier properties and interfacial adhesion in thinned organic layers via organically modified nanosheets， offering a promising pathway for developing high-performance， ultra-thin flexible encapsulation.