Chang Ming-Hsuan, Lee Lin-Ruei, Huang Meng-Ru, Tsai Tsung-Hung, Chen Yi-Fan, Hong Yu-Ting, Liu Yu-Chun, Chen Jiun-Tai
Department of Applied Chemistry, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan.
Center for Emergent Functional Matter Science, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan.
Langmuir. 2024 Jul 15;40(30):15941-8. doi: 10.1021/acs.langmuir.4c02410.
Hierarchical polymer structures have garnered widespread application across various fields owing to their distinct surface properties and expansive surface areas. Conventional hierarchical polymer structures, however, often lack postfabrication scalability and spatial selectivity. In this study, we propose a novel strategy to prepare light-assisted hierarchical polymer structures using azopolymers (PAzo), the breath figure method, and anodic aluminum oxide (AAO) templates. Initially, the breath figure PAzo films are prepared by dripping a PAzo chloroform solution onto glass substrates in a high-humidity environment. The AAO templates are then placed on the breath figure PAzo film. Upon ultraviolet (UV) light exposure, the azobenzene groups in the azopolymers undergo photoisomerization. This process causes the glass transition temperature () of the PAzo to become lower than room temperature, allowing the azopolymer to enter the nanopores of the AAO templates. The hierarchical azopolymer structures are then formed by using a sodium hydroxide solution to remove the templates. Furthermore, exploring the effects of PAzo concentration and UV light exposure duration on the film morphology reveals optimized conditions for hierarchical structure formation. Additionally, the water contact angles of these polymer structures are measured. The hierarchical PAzo structures exhibit higher hydrophobicity compared with the flat PAzo films and the PAzo breath figure films. Finally, patterned breath figure films can be prepared using designed photomasks, demonstrating the method's capability for spatial selectivity.
由于其独特的表面性质和较大的表面积，分级聚合物结构在各个领域都得到了广泛应用。然而，传统的分级聚合物结构往往缺乏制造后的可扩展性和空间选择性。在本研究中，我们提出了一种使用偶氮聚合物（PAzo）、呼吸图案法和阳极氧化铝（AAO）模板制备光辅助分级聚合物结构的新策略。首先，通过在高湿度环境中将PAzo氯仿溶液滴到玻璃基板上来制备呼吸图案PAzo薄膜。然后将AAO模板放置在呼吸图案PAzo薄膜上。在紫外线（UV）照射下，偶氮聚合物中的偶氮苯基团发生光异构化。这个过程使PAzo的玻璃化转变温度（）低于室温，从而使偶氮聚合物能够进入AAO模板的纳米孔中。然后用氢氧化钠溶液去除模板，形成分级偶氮聚合物结构。此外，通过探究PAzo浓度和紫外线照射时间对薄膜形态的影响，揭示了分级结构形成的优化条件。此外，还测量了这些聚合物结构的水接触角。与平面PAzo薄膜和PAzo呼吸图案薄膜相比，分级PAzo结构表现出更高的疏水性。最后，使用设计好的光掩膜可以制备图案化的呼吸图案薄膜，证明了该方法具有空间选择性的能力。
