不同温度响应温敏纳米二氧化硅的制备及其性能研究

发布时间：2018-03-05 16:14

本文选题：聚氧乙烯醚　切入点：温敏性　出处：《中国日用化学工业研究院》2015年硕士论文　论文类型：学位论文

【摘要】：温敏聚合物是指在水溶液中,当温度高于某一临界温度时,聚合物会经历从溶解到不溶的相转变过程,这一温度称为最低临界溶解温度(lower critical solution temperature,LCST)。N-异丙基丙烯酰胺(PNIPAAm)的LCST约为32oC,接近人体体温,是研究最为广泛的温敏聚合物,尤其在药物缓释方面有较广泛的应用。然而,PNIPAAm较低的LCST在其他方面如催化,就会受到温度上的限制。目前,将环境响应性聚合物与纳米粒子的光、电、生物等性能相结合,赋予纳米粒子智能特性,已经引起了人们广泛的研究兴趣。这种智能聚合物包覆的纳米粒子在智能光电器件、智能催化、分析检测、开关控制、药物缓释等领域有着巨大的潜在应用价值。本论文尝试制备聚乙二醇甲醚甲基丙烯酸酯(poly(ethylene glycol)methyl ether methacrylate,POEGMA)改性纳米Si O2,通过选择不同EO链长的POEGMA和外加添加剂的方法调控产物的LCST,得到能够对不同温度响应的多种温敏纳米Si O2,为进一步拓宽其应用范围创造条件。电子转移生成催化剂的原子转移自由基聚合(AGET ATRP)可以提高改性纳米Si O2的接枝率,从而提高聚氧乙烯醚改性纳米Si O2温敏响应性能,以满足实际应用需求。将制备的温敏纳米Si O2作为固体乳化剂制备了Pickering乳液,并对Pickering乳液的温敏性能进行了测试,为其实现在催化剂的高效分离和回收方面的应用奠定了理论基础。主要研究工作如下:(1)首先利用St?ber法制得了单分散的纳米Si O2,再利用γ-氨丙基三乙氧基硅烷(KH550)改性纳米Si O2制得Si O2-NH2,然后与2-溴异丁酰溴反应制备具有引发作用的Si O2-Br,最后利用AGET ATRP法用分子量为500的聚乙二醇甲醚甲基丙烯酸酯(POEGMA500)对纳米Si O2进行了表面改性,制备了LCST为90oC的改性纳米Si O2(Si O2-POEGMA500)。考察了反应温度、反应时间、催化剂/配体/还原剂摩尔比、Si O2-Br和单体用量等条件对温敏纳米Si O2接枝率的影响。利用傅立叶变换红外光谱仪(FT-IR)、X射线光电子能谱仪(XPS)、热重分析仪(TGA)、透射电子显微镜(TEM)和扫描电子显微镜(SEM)、紫外-可见分光光度计(UV-vis)、动态光散射(DLS)和相转变等对Si O2-POEGMA500的结构和温敏性能进行了系统表征。(2)采用优化的工艺条件,利用分子量为300聚乙二醇甲醚甲基丙烯酸酯(POEGMA300)对纳米Si O2进行了表面改性。考察了POEGMA500与POEGMA300复配体系对温敏纳米Si O2 LCST的调控作用。利用UV-vis、DLS、相转变、傅立叶衰减全反射红外光谱仪(ATR-FTIR)、XPS、TEM和SEM等方法对样品的温敏性能和结构进行了测试。考察了Na Cl、乙醇、十二烷基硫酸钠(SDS)等添加剂对上述温敏Si O2-POEGMA300 LCST的调控作用。(3)以Si O2-POEGMA500为固体颗粒乳化剂,室温下制备了稳定性较高的液体石蜡/水体系Pickering乳液。考察了固体颗粒用量、去离子水用量、液体石蜡用量、加料顺序和无机盐的加入等因素对Pickering乳液稳定性的影响。最后,对制备的Pickering乳液温敏性能进行了测试。
[Abstract]:Refers to the temperature sensitive polymer in aqueous solution, when the temperature is higher than a critical temperature, the polymer will experience from dissolved into the insoluble phase transition, this temperature is called the lower critical solution temperature (lower critical solution temperature, LCST).N- isopropylacrylamide (PNIPAAm) LCST is about 32oC, close to the body temperature is one of the most widely used temperature sensitive polymer, especially is widely used in drug delivery. However, low PNIPAAm LCST in other areas such as catalysis, will be temperature limit. At present, the environment responsive polymer nano particles and light, electricity, etc. the combination of biological properties, given the the characteristics of intelligent nanoparticles have attracted widespread interest in the study. This kind of intelligent polymer coated nanoparticles in intelligent photoelectric devices, intelligent catalysis, analysis and detection, switch control, drug release and other fields have a giant The potential application value. This paper attempts for the preparation of polyethylene glycol methyl ether methacrylate (poly (ethylene glycol) methyl ether methacrylate, POEGMA) modified Si nano O2, through the selection of different chain length of EO POEGMA and an external additive method to control product of LCST, can get on a variety of temperature sensitive nano Si O2 different temperature response and create conditions for further broaden its application range. The electron transfer catalyst generated by atom transfer radical polymerization (AGET ATRP) can improve the grafting modification of nano Si O2 rate, thereby improving the polyoxyethylene ether modified nano Si O2 temperature sensitive response performance, to meet the needs of practical application. The temperature sensitive nano Si preparation O2 as a solid emulsifier to prepare Pickering emulsion, and the temperature sensitive properties of Pickering emulsion were tested, is now the application of high efficiency catalyst separation and recovery of the establishes theory The foundation. The main work is as follows: (1) we use St? BER prepared monodisperse Si nano O2, using gamma aminopropyltriethoxysilane (KH550) modified Si nano O2 prepared Si O2-NH2, and then 2- bromo isobutyryl bromide reaction preparation has caused the effect of Si O2-Br finally, using the AGET ATRP method with molecular weight of polyethylene glycol methyl ether methacrylate 500 (POEGMA500) of nano Si surface modification of O2, preparation of LCST nano Si O2 90oC (Si O2-POEGMA500). The effects of reaction temperature, reaction time, catalyst / ligand / agent ratio, influence Si O2-Br and monomer dosage on the grafting rate of Si O2. The use of temperature sensitive nano Fu Liye transform infrared spectrometer (FT-IR), X ray photoelectron spectroscopy (XPS), thermogravimetric analyzer (TGA), transmission electron microscopy (TEM) and scanning electron microscopy (SEM), UV VIS spectrophotometer (UV-v Is), dynamic light scattering (DLS) and phase transition of Si O2-POEGMA500 structure and thermo sensitive properties were systematically characterized. (2) under optimized conditions, the molecular weight of 300 polyethylene glycol methyl ether methacrylate (POEGMA300) on the nano Si surface modification of O2 was studied. The regulation of POEGMA500 and POEGMA300 mixed system for temperature sensitive nano Si O2 LCST. Using UV-vis, DLS, phase transition, Fu Liye attenuated total reflection infrared spectroscopy (ATR-FTIR), XPS, thermo sensitive properties and structures of TEM and SEM of samples were tested. The effects of Na Cl, twelve ethanol, sodium dodecyl sulfate (SDS) Regulation Effect of additives on the temperature sensitivity of Si O2-POEGMA300 LCST. (3) to Si O2-POEGMA500 as solid particle emulsifiers, liquid paraffin / water system with high stability of Pickering emulsion was prepared at room temperature. The effects of the solid particle content, the amount of deionized water, The effects of liquid paraffin dosage, feeding sequence and inorganic salt addition on the stability of Pickering emulsion were studied. Finally, the temperature sensitivity of Pickering emulsion was tested.

【学位授予单位】：中国日用化学工业研究院
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ127.2;TB383.1

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