CAREER: Tailoring Photo-Switchable Interfaces using Functional Polymer Brushes

技术概要：该提案概述了一个5年计划，重点是了解光诱导的构象变化如何影响表面结合的聚合物刷的表面，界面和宏观性质的光致变色薄膜。 光致变色部分在延伸的聚合物链中的三维排列导致表面处的官能团密度增加，其可用于放大功能涂层的刺激响应性质。 本课题旨在利用表面引发聚合技术合成光致变色聚合物刷，完成以下三个研究目标：（1）利用光通过金属离子络合来控制光致变色聚合物的色度响应。将阐明和利用含螺吡喃的聚合物在不同金属离子存在下照射时发生的光诱导络合的可逆结合机制以产生可逆离子传感器。(2)研究可逆的光开关粘合。经历光致相分离的表面的设计将允许从粘合状态切换到非粘合状态的表面。(3)在单分子水平上研究光致机械运动。 光将用于诱导不同自由能的表面上的无规卷曲和延伸链之间的构象变化，从而导致光诱导的机械运动。使用光作为外部刺激来产生具有受控界面性质的功能表面将对各种科学发展产生重大影响，例如传感器、微流体装置、可控药物递送、光学数据存储、自清洁、防雾和防腐蚀表面。光作为刺激可以提供远程控制传感器响应的能力，具有高速度和空间精度。测量和量化的界面力参与光响应聚合物表面将有助于阐明响应材料的粘附的起源。在分子水平上研究光致运动将有助于加深对聚合物，特别是二维空间中聚合物的理解。 该项目的技术性质提供了一个跨学科的培训经验，研究生和本科生在聚合物合成和薄膜表征。 该培训将为学生提供解决聚合物科学家未来需求所需的技能。一个重要的外联部分，这一建议包括？夏令营？在格鲁吉亚大学为十名高中教师举办的一次研讨会旨在为教师提供涉及聚合物科学的简单实验，供他们在课堂上进行。这一外联项目的最终目标是通过影响年轻学生从事科学和工程职业，产生巨大的社会和经济影响。

TECHNICAL SUMMARY: This proposal outlines a 5 year plan centered on understanding how light-induced conformation changes in surface-bound polymer brushes influence surface, interfacial, and macroscopic properties in photochromic thin films. The three dimensional arrangement of photochromic moieties in extended polymer chains result in an increased density of functional groups at the surface that can be used to amplify the stimuli responsive nature of functional coatings. This proposal is aimed at synthesizing photochromic polymer brushes using surface initiated polymerization techniques that can be used to complete the following three research objectives: (1) Using light to control the colorimetric response of photochromic polymers through metal ion complexation. The reversible binding mechanism of photo-induced complexation that occurs when spiropyran containing polymers are irradiated in the presence of different metal ions will be elucidated and exploited to generate reversible ion sensors. (2) Investigating reversible, photo-switchable adhesion. The design of surfaces that undergo photo-induced phase separation will allow for surfaces that switch from adhesive to non-adhesive states. (3) Investigating photo-induced mechanical motion on the single molecule level. Light will be used to induce conformation changes between random coils and extended chains on surface of different free energy, leading to photo-induced mechanical motion.NON-TECHNICAL SUMMARY: The creation of functional surfaces with controlled interfacial properties using light as an external stimulus will have a major impact on a wide variety of scientific developments, such as sensors, microfluidic devices, controllable drug delivery, optical data storage, self-cleaning, antifogging and antifouling surfaces. Light as a stimulus can provide the ability to control sensor response remotely, with high speed and spatial precision. Measuring and quantifying the interfacial forces involved in photoresponsive polymer surfaces will help to elucidate the origins of adhesion in responsive materials. The understanding of polymers, especially in two-dimensional space, will be improved with the investigation of photo-induced motion at the molecular level. The technical nature of this project provides an interdisciplinary training experience to graduate and undergraduate students in polymer synthesis and thin film characterization. This training will provide students with the skill set necessary in addressing the future needs of polymer scientists. A significant outreach component of this proposal includes a ?summer camp? for ten high school teachers to be held at the University of Georgia is aimed at providing teachers with simple experiments involving polymer science to perform in their classrooms. The ultimate goal of this outreach project is to provide a large social and economic impact by influencing young students to pursue careers in science and engineering.