表面引发反向原子转移自由基聚合法制备亲疏水可逆响应的聚离子液体刷

发布时间：2018-06-18 20:08

本文选题：硅片 + RATRP　；参考：《西北师范大学》2011年硕士论文

【摘要】：润湿特性是固体表面的重要性质之一,其中超疏水表面是近年来表面润湿性研究领域的一个热点。尤其是对外界环境(如光照、电场、热和化学等)有刺激响应的表面亲疏水可逆转化材料更是引起了研究人员极大的关注。由于这类表面在智能装置领域有着潜在的应用前景,因此,合理设计并制备润湿性可控的表面,是实现固体润湿性多元化应用的关键环节。表面润湿性的调控可以通过两种途径实现:一种是表面微结构的调控,另一种是表面自由能调控。第二种途径是在保持材料表面形貌的条件下,利用外界环境的刺激作用定向改变材料表面化学组成从而改变表面自由能,使液滴在表面的接触角相应地发生变化。目前有多种调控固体表面自由能的方法,其中将聚合物刷,通过“Grafting from”技术接枝到各种基体表面,利用表面化学成分的不同对润湿性进行调控就是方法之一。多种聚合反应技术都可应用于“Grafting from”方法中,其中反向原子转移自由基聚合反应作为对传统的原子转移自由基聚合反应的改进和拓展,在制备预定结构、预定分子量以及窄分子量分布聚合物方面具有其它方法所无法替代的优点,成为今后高分子合成化学领域的研究热点。而室温离子液体是近年来绿色化学新兴研究领域之一,研究者充分利用离子液体的独特性质,在合成高分子量缩聚产物等方面取得了很大的研究进展,且对于不同的阴离子所对应的离子液体,其亲疏水性不同。因此,本文的研究内容主要包括: (1)离子液体单体的合成。通过两步法合成了三种双键功能化的吡啶类离子液体单体烯丙基吡啶六氟磷酸盐(ALPY-PF_6)、1-(4-乙烯基苄基-)-吡啶六氟磷酸盐(VBPy-PF_6)和1-苄基-1′-[4-(乙烯基)苄基]-4,4′-联吡啶六氟磷酸盐(BVBBP-PF_6),利用核磁共振等技术手段对它们进行了表征。 (2)硅片表面引发剂单分子层的固载。将表面引发剂2-溴-2-甲基-N-(3-(三乙氧基硅基)丙基)丙酰胺(BTPAm)以自组装的方式沉积在预处理过的硅片上,实验结果表明,表面固载的引发剂具有良好的的引发反向原子转移自由基聚合反应(RATRP)的能力。 (3)硅片表面接枝聚合物刷的制备以及润湿性的可逆调控。首先以烯丙基吡啶六氟磷酸盐、1-(4-乙烯基苄基-)-吡啶六氟磷酸盐和1-苄基-1′-[4-(乙烯基)苄基]-4,4′-联吡啶六氟磷酸盐为单体,CuC_(l2)/2,2′-联吡啶的络合物为催化体系,2-溴-2-甲基-N-(3-(三乙氧基硅基)丙基)丙酰胺(BTPAm)为表面引发剂,AIBN为自由基引发剂,环己酮为溶剂,在不同温度条件下,利用反向原子转移自由基聚合反应(RATRP)在硅片上接枝了聚离子液体刷,最后通过对阴离子交换,成功实现了材料表面亲疏水性的可逆转换。动力学研究结果表明利用RATRP在含有溴硅烷的硅表面接枝聚离子液体刷的过程是活性/可控的。
[Abstract]:Wettability is one of the important properties of solid surface, and superhydrophobic surface is a hot spot in the field of surface wettability research in recent years. In particular, surface hydrophobic reversible conversion materials with stimulative responses to external environments (such as light, electric field, heat and chemistry) have attracted much attention. Because this kind of surface has a potential application prospect in the field of intelligent device, it is the key link to realize the multiplex application of solid wettability to design and fabricate the wettable controllable surface reasonably. The regulation of surface wettability can be achieved by two ways: one is the regulation of surface microstructure and the other is the regulation of surface free energy. The second way is to change the surface chemical composition of the material and change the free energy of the surface by using the stimuli of the external environment under the condition of maintaining the surface morphology of the material, so that the contact angle of the droplets on the surface changes correspondingly. At present, there are many methods to control the free energy of solid surface, among which the polymer brushes are grafted onto various matrix surfaces by "lifting from" technique, and the wettability is regulated by the different chemical composition of the surface. A variety of polymerization techniques can be used in the "lifting from" method, in which the reverse atomic transfer radical polymerization is used as an improvement and extension of the conventional atomic transfer radical polymerization, in the preparation of a predetermined structure. The polymer with predetermined molecular weight and narrow molecular weight distribution has many advantages which can not be replaced by other methods, and has become a hotspot in the field of polymer synthesis chemistry in the future. Room temperature ionic liquid is one of the new research fields of green chemistry in recent years. Researchers have made great progress in the synthesis of high molecular weight Polycondensation products by making full use of the unique properties of ionic liquids. The hydrophobicity of ionic liquids corresponding to different anions is different. Therefore, the main contents of this study include: 1) synthesis of ionic liquid monomers. Three double bonded pyridine ionic liquid monomers, allyl pyridine hexafluorophosphate (ALPY-PF6) were synthesized by two step method. Fluorophosphate (BVBBP-PF6) was characterized by nuclear magnetic resonance (NMR). The surface initiator 2-bromo-2-methyl-N-n- (triethoxysilyl) propionamide BTPAmwas deposited on the pre-treated silicon wafer in a self-assembled manner. The experimental results showed that, The surface immobilized initiators have a good ability to initiate reverse atom transfer radical polymerization (RATRP). 3) preparation of graft polymer brushes on the surface of silicon wafers and reversible control of wettability. First of all, the complexes of allyl pyridine hexafluorophosphate, 1-butadiene-4-vinyl-benzyl-keto-pyridine-hexafluorophosphate and 1-benzyl-1- [4-( vinyl) benzyl] -4-dipyridyl hexafluorophosphate were used as the monomers of CuCC2N / 2O2-bipyridine as catalytic systems. Bromo-2-methyl-N-butadiene (triethoxysilyl) propamide (BTPAmA) was used as surface initiator and AIBN as free radical initiator. Cyclohexanone was used as solvent and the reverse atom transfer radical polymerization (RATRP) was used to graft polyionic liquid brush onto silicon wafer at different temperatures. Finally, the reversible conversion of hydrophobicity on the surface of the material was successfully realized by exchange of anions. The kinetic results show that the process of grafting polyionic liquid brush with RATRP on the surface of silane containing bromosilane is active / controllable.
【学位授予单位】：西北师范大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：O631.5

【参考文献】