Université Lille, UMR 8207-UMET-Unité Matériaux et Transformations , F-59000 Lille, France.
ENSCL , F-59000 Lille, France.
Langmuir. 2017 Apr 11;33(14):3434-3443. doi: 10.1021/acs.langmuir.7b00160. Epub 2017 Mar 29.
In this article, we report on the reversible tethering of end-functionalized polymers onto catechol-based titanium platforms by exploiting the reversible Diels-Alder (DA) cycloaddition reaction. For this purpose, furan and maleimide end-functionalized polymers, prepared via reversible addition-fragmentation chain transfer polymerization, were covalently grafted through a DA reaction onto reactive titanium platforms elaborated from catechol-based anchors incorporating either the furan or the maleimide moiety. As a proof of concept, a hydrophilic poly(oligo(ethylene glycol)acrylate) (POEGA) and a hydrophobic poly(2,2,2-trifluoroethyl acrylate) (PTFEA) were grafted onto titanium surfaces and subsequently detached by exploiting the thermoreversible nature of the DA reaction [i.e., retro Diels-Alder (rDA)]. These polymers were interchanged by performing a second DA reaction, thereby allowing the titanium surface wettability to be switched from hydrophobic to hydrophilic on demand. The grafting of furan/maleimide end-functionalized polymers onto functionalized (maleimide/furan, respectively) catechol-based titanium platforms and the subsequent rDA/DA sequence used for switching the titanium surface were evidenced by attenuated total reflectance-Fourier transform-infrared spectroscopy, X-ray photoelectron spectroscopy, and contact angle measurements.
本文报告了通过利用可逆 Diels-Alder（DA）环加成反应，将端基官能化聚合物可逆地固定在基于儿茶酚的钛平台上。为此，通过可逆加成-断裂链转移聚合制备了呋喃和马来酰亚胺端基官能化聚合物，通过 DA 反应将其共价接枝到由包含呋喃或马来酰亚胺部分的基于儿茶酚的锚定剂制备的反应性钛平台上。作为概念验证，亲水性聚（聚（乙二醇）丙烯酸酯）（POEGA）和疏水性聚（2,2,2-三氟乙基丙烯酸酯）（PTFEA）被接枝到钛表面上，并通过利用 DA 反应的热可逆性（即反式 Diels-Alder（rDA））将其脱附。通过进行第二次 DA 反应，这些聚合物可以相互交换，从而可以按需切换钛表面的润湿性，从疏水性变为亲水性。通过衰减全反射傅里叶变换红外光谱、X 射线光电子能谱和接触角测量，证明了呋喃/马来酰亚胺端基官能化聚合物接枝到官能化（分别为马来酰亚胺/呋喃）基于儿茶酚的钛平台上，以及随后用于切换钛表面的 rDA/DA 序列。
