本文選題：可逆加成-斷裂鏈轉(zhuǎn)移聚合 + 刺激響應�。� 參考：《中國科學技術大學》2017年博士論文

【摘要】：響應性聚合物和功能性聚烯烴是目前國內(nèi)外高分子界異�；钴S的領域。近年來,可控/活性聚合的發(fā)展,使得單體以可控的方式進行聚合成為可能。本文通過設計具有功能性的單體,利用可逆加成-斷裂鏈轉(zhuǎn)移(RAFT)聚合,制備了具有不同環(huán)境響應的聚合物及功能化的聚烯烴。論文主要研究內(nèi)容包括以下四個部分:1、利用RAFT聚合反應一鍋法制備刺激響應的超支化聚合物,將其加入水中制備了多刺激響應的凝膠粒子。研究表明,聚合物具有溫度敏感性,當溫度升至低臨界溶液溫度(LCST)以上時,其溶解能力大大降低,形成納米粒子,隨后,分子間發(fā)生二硫鍵的交換反應交聯(lián)納米粒子而形成了納米凝膠。這種納米凝膠具有溫度、光和還原響應性。2、通過RAFT聚合制備了含有二硫鍵的PEG超支化聚合物,考察了其溫度響應性和自交聯(lián)的反應條件。然后將超聲分散于水中的SiO2納米粒子作為模板,通過控制pH、溫度和聚合物濃度等手段,利用微量進樣器來連續(xù)滴加,獲得了 PEG/SiO2核殼結構的納米粒子。并在此基礎上,通過HF腐蝕內(nèi)核SiO2,得到了可生物降解的PEG納米空心膠囊。3、聯(lián)合陰離子開環(huán)反應和RAFT聚合,一鍋法制備了環(huán)硫丙烷和異丙基甲基丙烯酰胺、環(huán)硫丙烷和N,N-二甲基丙烯酰胺的共聚物。S-1-十二烷基-S'-(α,α'-二甲基-α"-乙酸)三硫代碳酸酯為丙烯酰胺類單體RAFT聚合的鏈轉(zhuǎn)移劑和環(huán)硫丙烷開環(huán)聚合(ROP)的引發(fā)劑。實驗結果表明,制備的環(huán)硫丙烷與異丙基甲基丙烯酰胺共聚物由于含有親水和疏水段,在室溫下自組裝成膠束。當暴露在活性氧的環(huán)境中時,聚環(huán)硫丙烷(PPS)轉(zhuǎn)變成親水的聚丙烯砜(PPP),此時膠束解聚成溶液。再次升高溫度至聚異丙基甲基丙烯酰胺(PNIPMAM)的LCST以上時,新的膠束再次形成。使用活性氧和溫度作為刺激方式在藥物釋放方面具有潛在的應用前景。4、溫和條件下(T=70℃,P≤30bars)利用RAFT聚合成功合成了一系列功能性的聚乙烯材料。該方法制備的共聚物具有較高的分子量、窄分布(Mn10000 g/mol,PDI1.3)和可調(diào)控的極性單體的插入比,拓展了功能性聚烯烴的合成思路。
[Abstract]:Reactive polymers and functional polyolefin are very active in the field of polymer industry at home and abroad. In recent years, the development of controllable / active polymerization has made it possible to polymerize monomers in a controllable manner. In this paper, functional monomers were designed and polymerized by reversible addition-break chain transfer (raft) to prepare polymers and functionalized polyolefin with different environmental responses. The main contents of this paper are as follows: 1. The hyperbranched polymers with stimulus response were prepared by the one-pot method of raft polymerization, and the multi-stimuli responsive gel particles were prepared by adding them into water. The results show that the polymer is temperature-sensitive, and when the temperature rises above the low critical solution temperature (LCST), the solubility of the polymer decreases greatly, forming nanoparticles, and then, Exchange reaction of disulfide bond between molecules and crosslinking of nanoparticles to form nanogels. The nanogel was characterized by temperature, light and reductive responsiveness. PEG hyperbranched polymers containing disulfide bonds were prepared by raft polymerization. The temperature response and the reaction conditions of self-crosslinking were investigated. Then the Sio _ 2 nanoparticles dispersed in water by ultrasonic were used as templates. By controlling pH, temperature and polymer concentration, the PEG / Sio _ 2 core-shell nanoparticles were obtained by using a micro sampler. On this basis, biodegradable PEG nano-hollow capsules. 3 were prepared by HF corrosion core SiO2, combined with anionic ring-opening reaction and raft polymerization. Cyclothiopropane and isopropylmethacrylamide were prepared by one-pot method. The copolymers of cyclothiopropane and N-dimethylacrylamide. S-1- dodecyl (偽, 偽 -dimethyl- 偽 "-acetic acid) trithiocarbonate is the chain transfer agent and initiator of cyclic thiopropane ring-opening polymerization (ROP) for acrylamide monomer raft polymerization. The experimental results show that the prepared copolymers of cyclothiopropane and isopropylmethacrylamide are self-assembled into micelles at room temperature due to their hydrophilic and hydrophobic segments. When exposed to reactive oxygen species, polycyclic thiopropane (PPS) is transformed into hydrophilic polypropylene sulfone (PPP), and the micelle is decomposed into solution. When the temperature is raised again above the LCST of PNIPMAM, the new micelles are formed again. A series of functional polyethylene materials were successfully synthesized by raft polymerization under mild conditions (T _ (70 鈩，

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