RAFT分散聚合制備熱敏性的納米顆粒
發(fā)布時間：2018-08-24 15:59
【摘要】：近年來,可逆加成斷裂鏈轉(zhuǎn)移(RAFT)聚合在合成結(jié)構(gòu)明確、分子量可控的高分子方面取得了重大的進(jìn)展,引起了人們極大的興趣。本論文,通過RAFT聚合制備了兩種熱敏性納米顆粒。首先,利用聚N-異丙基丙烯酰胺(PNIPAM)在混合溶劑中的非共溶劑效應(yīng),即PNIPAM在兩種良溶劑的混合溶劑中,溶解性反而變差的現(xiàn)象。選擇乙醇和水混合液作為溶劑,利用RAFT分散聚合的方法合成了多種組分、結(jié)構(gòu)和功能的熱敏性納米凝膠。其次,利用RAFT分散聚合先合成臂的方法,選用親水性的聚N,N-二甲基丙烯酰胺(PDMA)和熱敏性的PNIPAM作為高分子臂,水作為溶劑,合成出熱敏性的雜臂星形高分子,并研究了其作為乳化劑的應(yīng)用。主要研究內(nèi)容如下:1.選擇75:25(v/v)的水-乙醇溶劑作為反應(yīng)溶劑,PDMA作為大分子鏈轉(zhuǎn)移劑,RAFT分散聚合NIPAM,成功制備出熱敏性的納米凝膠。用凝膠滲透色譜(GPC)和核磁(NMR)氫譜進(jìn)行表征,發(fā)現(xiàn)RAFT控制良好,聚合動力學(xué)曲線呈線性關(guān)系。系統(tǒng)地研究了大分子鏈轉(zhuǎn)移劑PDMA的分子量、固體含量、交聯(lián)劑用量對合成納米凝膠的影響。結(jié)果顯示,高PNIPAM聚合度、高固體含量、高交聯(lián)劑濃度時,更容易形成穩(wěn)定的納米凝膠。將親水性單體N-(2-羥乙基)丙烯酰胺(HEAM),雙丙酮丙烯酰胺(DAAM)及疏水性單體丙烯酸正丁酯(BA),熒光素-O-丙烯酸酯(FLA),1,6-己二醇二丙烯酸酯(HDDA)分別與NIPAM共聚,利用RAFT分散聚合成功制備出多組分、功能化的納米凝膠。另外,兩親性嵌段共聚物PDMA-b-PBA用作大分子鏈轉(zhuǎn)移劑,成功制備出三嵌段的納米凝膠。納米凝膠的熱敏性通過動態(tài)光散射(DLS)進(jìn)行表征。2.我們選用親水性的PDMA和熱敏性的PNIPAM作為高分子臂,1,6-己二醇二丙烯酸酯(HDDA)作為交聯(lián)劑,抗壞血酸(ASA)和叔丁基過氧化氫(t-Bu OH)作為引發(fā)劑,水為反應(yīng)溶劑,成功地制備出熱敏性的雜臂星形高分子。通過控制兩種鏈的投料比例來調(diào)節(jié)星形高分子中兩種高分子臂的比例,從而改變星形高分子的低臨界溶解溫度(LCST),發(fā)現(xiàn)制備的雜臂星形高分子確實(shí)具有明顯的熱敏性,而且改變PNIPAM比例,星形高分子的LCST會發(fā)生變化。用各種不同LCST的星形高分子作為乳化劑,制備了一系列乳液,使用共聚焦顯微鏡觀察形成乳液的形貌,證明了雜臂星形高分子有很好的乳化能力。
[Abstract]:In recent years, reversible addition chain transfer (RAFT) polymerization has made great progress in the synthesis of polymers with clear structure and controllable molecular weight, which has aroused great interest. In this thesis, two kinds of thermosensitive nanoparticles were prepared by RAFT polymerization. Firstly, the non-co-solvent effect of poly (N-isopropylacrylamide) (PNIPAM) in mixed solvents is used, that is, the solubility of PNIPAM in two good solvents becomes worse. Thermosensitive nanogels with various components, structures and functions were synthesized by RAFT dispersion polymerization with ethanol and water mixture as solvents. Secondly, the thermosensitive hetero-arm star polymer was synthesized by the method of RAFT dispersion polymerization, the hydrophilic poly (N- N- dimethylacrylamide) (PDMA) and the thermosensitive PNIPAM were used as the polymer arm and the water as the solvent to synthesize the thermosensitive hetero-arm star polymer. Its application as emulsifier was also studied. The main research contents are as follows: 1. The thermosensitive nanogels were successfully prepared by using the water-ethanol solvent of 75:25 (v / v) as the reaction solvent and NIPAM, as the macromolecular chain transfer agent. Gel permeation chromatography (GPC) and nuclear magnetic field (NMR) hydrogen spectra were used to characterize the results. It was found that RAFT was well controlled and the polymerization kinetics curve was linear. The effects of molecular weight, solid content and crosslinking agent amount of macromolecular chain transfer agent (PDMA) on the synthesis of nanogels were systematically studied. The results showed that stable nanogels were more easily formed with high PNIPAM polymerization degree, high solid content and high crosslinking agent concentration. The hydrophilic monomer N- (2-hydroxyethyl) acrylamide (HEAM), diacetone acrylamide (DAAM) and hydrophobic monomer n-butyl acrylate (BA), fluorescein (HDDA) were copolymerized with NIPAM, respectively. Multicomponent and functionalized nanogels were successfully prepared by RAFT dispersion polymerization. In addition, amphiphilic block copolymer PDMA-b-PBA was used as macromolecular chain transfer agent to successfully prepare triblock nanogels. The thermal sensitivity of nanogels was characterized by dynamic light scattering (DLS). Hydrophilic PDMA and thermosensitive PNIPAM were used as crosslinking agent, ascorbic acid (ASA) and tert-Ding Ji hydrogen peroxide (t-Bu OH) as initiator and water as solvent. The thermosensitive hetero-arm star polymer was successfully prepared. By controlling the feeding ratio of two chains to adjust the ratio of two kinds of polymer arms, it is found that the hetero-arm star polymer has obvious thermal sensitivity by changing the low critical dissolution temperature (LCST),) of the star polymer. And changing the ratio of PNIPAM, star polymer LCST will change. A series of emulsions were prepared by using different LCST starlike polymers as emulsifiers. The morphology of the emulsion was observed by confocal microscope.
【學(xué)位授予單位】：上海大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TB383.1
本文編號：2201312
[Abstract]:In recent years, reversible addition chain transfer (RAFT) polymerization has made great progress in the synthesis of polymers with clear structure and controllable molecular weight, which has aroused great interest. In this thesis, two kinds of thermosensitive nanoparticles were prepared by RAFT polymerization. Firstly, the non-co-solvent effect of poly (N-isopropylacrylamide) (PNIPAM) in mixed solvents is used, that is, the solubility of PNIPAM in two good solvents becomes worse. Thermosensitive nanogels with various components, structures and functions were synthesized by RAFT dispersion polymerization with ethanol and water mixture as solvents. Secondly, the thermosensitive hetero-arm star polymer was synthesized by the method of RAFT dispersion polymerization, the hydrophilic poly (N- N- dimethylacrylamide) (PDMA) and the thermosensitive PNIPAM were used as the polymer arm and the water as the solvent to synthesize the thermosensitive hetero-arm star polymer. Its application as emulsifier was also studied. The main research contents are as follows: 1. The thermosensitive nanogels were successfully prepared by using the water-ethanol solvent of 75:25 (v / v) as the reaction solvent and NIPAM, as the macromolecular chain transfer agent. Gel permeation chromatography (GPC) and nuclear magnetic field (NMR) hydrogen spectra were used to characterize the results. It was found that RAFT was well controlled and the polymerization kinetics curve was linear. The effects of molecular weight, solid content and crosslinking agent amount of macromolecular chain transfer agent (PDMA) on the synthesis of nanogels were systematically studied. The results showed that stable nanogels were more easily formed with high PNIPAM polymerization degree, high solid content and high crosslinking agent concentration. The hydrophilic monomer N- (2-hydroxyethyl) acrylamide (HEAM), diacetone acrylamide (DAAM) and hydrophobic monomer n-butyl acrylate (BA), fluorescein (HDDA) were copolymerized with NIPAM, respectively. Multicomponent and functionalized nanogels were successfully prepared by RAFT dispersion polymerization. In addition, amphiphilic block copolymer PDMA-b-PBA was used as macromolecular chain transfer agent to successfully prepare triblock nanogels. The thermal sensitivity of nanogels was characterized by dynamic light scattering (DLS). Hydrophilic PDMA and thermosensitive PNIPAM were used as crosslinking agent, ascorbic acid (ASA) and tert-Ding Ji hydrogen peroxide (t-Bu OH) as initiator and water as solvent. The thermosensitive hetero-arm star polymer was successfully prepared. By controlling the feeding ratio of two chains to adjust the ratio of two kinds of polymer arms, it is found that the hetero-arm star polymer has obvious thermal sensitivity by changing the low critical dissolution temperature (LCST),) of the star polymer. And changing the ratio of PNIPAM, star polymer LCST will change. A series of emulsions were prepared by using different LCST starlike polymers as emulsifiers. The morphology of the emulsion was observed by confocal microscope.
【學(xué)位授予單位】：上海大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TB383.1
【參考文獻(xiàn)】
相關(guān)期刊論文 前1條
1 顧婷;查劉生;;相轉(zhuǎn)變溫度范圍窄的聚(N-異丙基丙烯酰胺)溫敏性微凝膠[J];功能高分子學(xué)報;2007年03期
，本文編號：2201312
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