功能性聚倍半硅氧烷微球的制备、表征及其应用研究

发布时间：2018-05-29 14:56

本文选题：聚倍半硅氧烷 + PSQ-SH微球　；参考：《江南大学》2017年硕士论文

【摘要】：聚倍半硅氧烷(PSQ)微球是一类在分子水平上杂化的新型材料,广泛应用于塑料、纤维、涂料、阻燃材料、化妆品、水处理、光学及生物医学等诸多领域。目前,功能性PSQ微球的制备及其应用研究不仅是材料领域的研究热点,同时也吸引了众多工业领域的关注。本学位论文围绕功能性PSQ微球的制备、表征及其应用研究,主要开展了以下几方面的工作:首先,采用改进的水解缩合一步法成功制备了粒径可控的聚甲基倍半硅氧烷(PMSQ)微球和巯基功能化聚倍半硅氧烷(PSQ-SH)微球,制备过程不需要用到有机溶剂和表面活性剂,并采用多种表征方法对PMSQ、PSQ-SH微球的结构、形貌及性能进行了测试。研究结果表明:通过改变油水比、氨水用量、温度等反应条件可以有效地调控PSQ微球的粒径及形貌;PSQ微球的形成过程主要包括了有机三甲氧基硅氧烷自水解、均相成核和核生长等步骤。PMSQ和PSQ-SH微球均含有半笼型、梯形和网状结构,而且PSQ-SH微球的倍半硅氧烷分子间距比PMSQ微球的大。PMSQ和PSQ-SH微球具有良好的热稳定性和疏水性,随着巯丙基三甲氧基硅氧烷(MPTMS)用量的增加,PSQ-SH微球的耐热和疏水性能均有所下降。其次,将PSQ-SH微球用作吸附剂,采用静态吸附法,系统研究了PSQ-SH微球对水溶液中银离子的吸附性能。PSQ-SH微球对银离子表现出优异的吸附性能:25℃下、银离子初始浓度为0.025mol/L时,PSQ-SH微球对银离子的最大吸附容量为750.21 mg/g。PSQ-SH微球对银离子的吸附更加吻合Langmuir等温吸附模型,表明该吸附主要为单分子层吸附;吸附动力学更适合拟二级动力学吸附模型。吸附热力学参数表明该吸附过程为自发进行的吸热过程,升温有利于PSQ-SH微球对银离子的吸附。PSQ-SH微球吸附银离子的过程不仅发生了化学离子交换,而且还伴随有化学氧化还原的发生。此外,在Ag+~Cu2+、Ag+~Zn2+、Ag+~Cd2+二元竞争吸附体系中,PSQ-SH微球表现出对银离子良好的吸附选择性;吸附-解吸循环实验表明PSQ-SH微球具有良好的再生和重复使用性能。最后,以PSQ-SH微球为载体,采用简易的原位还原法成功制备了载纳米银PSQ-SH(Ag/PSQ-SH)复合微球,制备过程中不需要添加额外的还原剂和稳定剂,并系统考察了Ag/PSQ-SH复合微球的抗菌性能。Ag/PSQ-SH复合微球的形成主要历经巯基去质子化、亲电攻击和银纳米粒子生长3个过程。通过改变反应时间、银氨溶液浓度、体系的pH可以有效地调控Ag/PSQ-SH复合微球的形貌。将Ag/PSQ-SH复合微球用作抗菌剂,以革兰氏阴性菌大肠杆菌(E.col)和革兰氏阳性菌金黄色葡萄球菌(S.au)作为主要的模型菌株,分别测定了Ag/PSQ-SH复合微球对E.col和S.au的抑菌圈、最小抑菌浓度(MIC)和最小杀菌浓度(MBC),结果表明:Ag/PSQ-SH复合微球对E.col和S.au具有优异的抗菌性能,抗菌活性随着银纳米粒子负载量的增加而增大。
[Abstract]:Polysiloxane (PSQ) microspheres are a new type of hybrid materials at the molecular level. They are widely used in many fields, such as plastics, fibers, coatings, flame retardants, cosmetics, water treatment, optics and biomedicine. At present, the preparation and application of functional PSQ microspheres is not only a hot topic in the field of materials, but also attracted a great deal of attention. This dissertation focuses on the preparation, characterization and application of functional PSQ microspheres. First, the improved hydrolytic condensation one step method has been used to successfully prepare the particle size controlled polymethylsilsesquioxane (PMSQ) microspheres and Mercapto functionalized polysiloxane (PSQ-SH) microspheres. The structure, morphology and properties of PMSQ and PSQ-SH microspheres are tested by various characterization methods. The results show that the particle size and morphology of PSQ microspheres can be effectively controlled by changing the oil water ratio, the amount of ammonia water and temperature, and the formation process of the PSQ microspheres is the main process. The.PMSQ and PSQ-SH microspheres contain semi cage, trapezoid and reticular structure, and the distance between the PSQ-SH microspheres and the large.PMSQ and PSQ-SH microspheres of the PMSQ microspheres has a good thermal stability and hydrophobicity with the thiol propyl trimethoxy silicon. The heat and hydrophobicity of PSQ-SH microspheres decreased with the increase of the amount of oxyalkane (MPTMS). Secondly, the PSQ-SH microspheres were used as adsorbents. The adsorption properties of PSQ-SH microspheres on the adsorption properties of silver ions in aqueous solution were systematically studied by.PSQ-SH microspheres. The initial concentration of silver ions at 25 centigrade was 0. At 25mol/L, the maximum adsorption capacity of PSQ-SH microspheres to silver ions is 750.21 mg/g.PSQ-SH microspheres, and the adsorption of silver ions is more consistent with the adsorption model of Langmuir isothermal adsorption. It shows that the adsorption is mainly a single molecular layer adsorption, and the adsorption kinetics is more suitable for the quasi two stage kinetic adsorption model. The process of heat absorption is beneficial to the adsorption of silver ions by PSQ-SH microspheres on the adsorption of silver ions by.PSQ-SH microspheres, not only is chemical ion exchange, but also with chemical oxidation reduction. In addition, in the competitive adsorption system of Ag+~Cu2+, Ag+~Zn2+, Ag+~Cd2+ two elements, PSQ-SH microspheres show good adsorption selection of silver ions. The adsorption desorption cycle experiments showed that the PSQ-SH microspheres had good regenerative and reusable properties. Finally, the nano silver PSQ-SH (Ag/PSQ-SH) composite microspheres were successfully prepared by a simple in situ reduction method with PSQ-SH microspheres as the carrier. The reduction agent and stabilizer were not needed in the preparation process, and Ag/PSQ-SH was systematically investigated. The formation of.Ag/PSQ-SH composite microspheres mainly through the sulfhydryl dehydrated, electrophilic attack and the growth of silver nanoparticles in 3 processes. By changing the reaction time, the concentration of silver ammonia solution and the pH of the system can effectively regulate the morphology of the Ag/PSQ-SH composite microspheres. The Ag/ PSQ-SH composite microspheres are used as an antibacterial agent, and gram Yin is used as an antiseptic. As the main model strain, the bacteria Escherichia coli (E.col) and gram-positive Staphylococcus aureus (S.au) were used as the main model strains. The bacteriostasis circle of Ag/PSQ-SH composite microspheres to E.col and S.au, the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) were respectively measured. The results showed that Ag/ PSQ-SH composite microspheres had excellent antibacterial properties to E.col and S.au, and the antibacterial activity of Ag/ PSQ-SH composite microspheres was excellent. The activity increased with the increase of the loading of silver nanoparticles.
【学位授予单位】：江南大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O634.41

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