Abstract The rapid development of optoelectronic devices puts forward higher requirements for flexible transparent films with good mechanical and thermal properties. To further improve the mechanical, thermal and optical properties of the PVA-co-PE nanofiber reinforced epoxy composite film, cellulose nanocrystals (CNCs) was selected as modifier to enhance the interfacial adhesion between the reinforced nanofibers and matrix. Benefiting from excellent hydrophily, high strength, transparency and ultra-low thermal expansion coefficient (CTE) of CNCs, dramatic improvements in tensile strength, transparency and thermal stability of CNCs/PVA-co-PE/epoxy composites were observed over pure PVA-co-PE nanofiber/epoxy film. Typically, when the CNCs concentration was 3%, the transparency of CNCs/PVA-co-PE/epoxy film increased from 83.4% to 90.4%, the tensile strength increased from 11.4 MPa to 16.4 MPa, the CTE dropped from 33 to 10 ppm/K. Furthermore, as the reinforcement for matrix and the carrier for functional materials, the CNCs/PVA-co-PE nanofiber membrane was used to prepare the patterned photochromic and thermochromic films encapsulated with epoxy, indicating the potential application of CNCs/PVA-co-PE/epoxy composites in the light emitting devices.

中文翻译：

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具有纤维素纳米晶体的 PVA-co-PE 纳米纤维/环氧树脂复合材料的机械、热和光学性能的协同改进

摘要 光电器件的快速发展对具有良好机械性能和热性能的柔性透明薄膜提出了更高的要求。为了进一步提高 PVA-co-PE 纳米纤维增强环氧树脂复合膜的机械、热学和光学性能，选择纤维素纳米晶体 (CNCs) 作为改性剂，以增强增强纳米纤维与基体之间的界面粘合力。得益于 CNCs 优异的亲水性、高强度、透明度和超低热膨胀系数 (CTE)，与纯 PVA-co 相比，CNCs/PVA-co-PE/环氧树脂复合材料的拉伸强度、透明度和热稳定性得到显着改善-PE纳米纤维/环氧树脂薄膜。通常，当CNCs浓度为3%时，CNCs/PVA-co-PE/环氧薄膜的透明度从83.4%提高到90.4%，拉伸强度从 11.4 MPa 增加到 16.4 MPa，CTE 从 33 ppm/K 下降到 10 ppm/K。此外，作为基体的增强剂和功能材料的载体，CNCs/PVA-co-PE纳米纤维膜用于制备环氧树脂封装的图案化光致变色和热致变色薄膜，表明CNCs/PVA-co-PE的潜在应用/环氧树脂复合材料在发光器件中。