聚合、交联进程分离的水凝胶涂层制备及其抗生物粘附性能

Anti-biofouling hydrogel coating is one of the ideal anti-biofouling materials. However, the single-step synthesis of hydrogel coating driven solely by free radical polymerization makes it hard to separate crosslinking from the polymerization process. Indeed, the undividable processing pattern gives rise to harsh preparation conditions and environmental pollution, which severely limits its practical application. The introduction of green and mild crosslinking reaction in addition to polymerization is an effective means to solve the above problems, because the continuous control of crosslinking reaction make it possible to separate the processes between the polymerization and crosslinking. Here, we propose to introduce silane coupling molecules as crosslinking agents, which serves to separate crosslinking from the polymerization process in a controllable manner, and thus establish a green and mild preparation method of hydrogel coating. In this proposal, we will focus on studying and elucidating the mechanism of tuning crosslinking rate by varying the chemical composition, structure and reaction conditions of silane coupling groups. We will make deep understanding about the influence and mechanism of the key reaction factors such as concentration of silane coupling molecules, polymer chain length etc. We will make implement of calcium alginate as a physical network to further improve the mechanical properties of the coating. On this basis, the zwitterionic hydrogel coating will be regulated by the chemical composition and ratio between positive and negative ionic groups on the zwitterionic monomer units, aiming at optimizing its anti-biofouling performance. Through this research, we will establish theoretical and experimental fundamentals for preparing mechanically stable, anti-biofouling hydrogel coating under green and mild condition.

抗生物粘附水凝胶涂层是理想的新型防生物污损材料之一。但目前经由自由基聚合反应一步合成水凝胶的技术路线中，聚合、交联进程无法分离，导致制备条件苛刻、环境污染等问题，是限制其应用的瓶颈。在单体聚合的基础上，引入绿色温和的交联反应，实现聚合、交联进程分离并连续可控，是解决上述问题的有效手段。本项目拟引入硅烷偶联分子作为交联剂，实现聚合、交联进程的连续可控分离，建立绿色、温和的水凝胶涂层制备方法。着重研究并阐明硅烷偶联基团的化学组成、结构以及反应条件对交联进程的调控规律，深入理解硅烷偶联分子的浓度、聚合物链长等因素对水凝胶涂层力学性能的调节机制，并引入海藻酸钙物理交联手段提高涂层的力学性能。在此基础上，通过设计单体正负离子基团的化学组成，调控水凝胶涂层的电离平衡，进一步优化其抗生物粘附性。本项目可以为绿色温和制备具有优异力学性能的抗生物粘附水凝胶涂层提供理论依据和实验基础。

凝胶涂层材料因其一系列固有特性，如高含水量、超亲水性、三维网络结构，与人体组织相似的柔性和顺应性，高透光性以及离子导电特性等，在植/入医疗、脑机接口、软机器人、可穿戴健康监测设备以及抗污/防污设施等方面具有广泛的应用前景。然而目前合成凝胶涂层材料可供利用的方法共同存在着合成条件苛刻、毒性高和污染环境等负面因素。本项目首先开展了包含硅烷功能单体共聚物的凝胶合成新策略研究。实现了聚合、交联分步制备合成凝胶涂层材料的新策略。验证了该策略在合成凝胶体系中良好的泛用性。进一步，向该体系中引入海藻酸钙物理网络。在充分保留了分步制备特色的情况下，显著提高了凝胶涂层的力学稳定性。并实际演示了该策略在大面积制备、弹性基底增强等方面的独特优势。在此基础上，针对硅烷偶联反应可控性差的问题，提出了双功能混合溶剂体系，不仅从根本上解决了硅烷凝胶涂料的寿命问题，同时通过对双溶剂中挥发组分的比例调控，使凝胶涂层的功能特性，包括强度、模量、韧性以及抗溶胀性、抗菌防污性和防雾防霜特性均获得了大幅提升。发展了基于硅烷化学过程的凝胶涂层分步制备新范式，为功能凝胶涂层在多个医疗和工程领域内的应用。