【作者】 王蕊欣；

【导师】 高保娇；

【作者基本信息】 中北大学 ， 应用化学， 2006， 硕士

【摘要】 本文首先合成了组成系列变化的丙烯酰胺(AM)与4-乙烯基吡啶(4VP)的共聚物[P(4VP -co-AM)],用硫酸二甲酯将其季铵化,制备了阳离子度及分子量系列变化的吡啶季铵盐型阳离子聚丙烯酰胺[Quaternary P(4VP -co-AM), QPVA];以大肠杆菌为致病菌体,重点研究了吡啶季铵盐型阳离子聚丙烯酰胺的分子链微结构与其抗菌性能的关系,采用平板活菌计数法考察了QPVA的阳离子度、分子量及pH值等因素对其抗菌性能的影响规律;采用β-半乳糖苷酶活性测定法与TTC—脱氢酶活性测定法两种方法,探索了吡啶季铵盐型阳离子聚丙烯酰胺的抗菌机理。然后,使用偶联剂γ-(甲基丙烯酰氧)丙基三甲氧基硅烷(KH-570)对微米级硅胶进行了表面化学改性,将双键引至SiO2粒子表面,以SiO2-苯乙烯为模型接枝聚合体系,分别采用溶液聚合与分散聚合两种方法,在硅胶表面实施了接枝聚合,重点考察了聚合方法对接枝聚合过程的影响规律。通过以上研究,为硅胶表面接枝聚4-乙烯基吡啶季铵盐型水不溶抗菌材料的制备及抗菌特性的研究奠定了一定的理论基础。最后,采用分散聚合的方法,在硅胶表面实施了丙烯酰胺(AM)与4-乙烯基吡啶(4VP)的接枝共聚合,分别用氯化苄和硫酸二甲酯将其季铵化,制备了接枝率系列变化的水不溶抗菌材料——硅胶接枝吡啶季铵盐型阳离子聚丙烯酰胺[Quaternary P(4VP -co-AM)/SiO2, QPVA/SiO2]。以大肠杆菌为致病菌体,重点研究了QPVA/SiO2的抗菌性能,采用平板活菌计数法考察了QPVA/SiO2的接枝率以及不同季铵化试剂对QPAV/SiO2抗菌性能的影响规律;采用β-半乳糖苷酶活性测定法,探索了吡啶季铵盐型阳离子聚丙烯酰胺的抗菌机理。研究结果表明:(1)吡啶季铵盐型阳离子聚丙烯酰胺具有很强的抗菌能力,且影响QPVA抗菌性能的主要因素是阳离子度、分子量与pH值:阳离子度越高,抗菌性能越强;在一定范围内,pH值越高,抗菌性能越好;分子量越高,抗菌性越强。β-半乳糖苷酶活性测定与TTC—脱氢酶活性测定结果表明,吡啶季铵盐型大分子的抗菌机理是基于杀菌作用,而不仅仅是抑菌作用;更多还原

【Abstract】 The copolymer of acrylamide and 4-vinyl pyridine was synthesized. Then it wasquaternarized by using sulphate of dimethyl, and two series of cationic polyacrylamide ofquaternary pyridine salt-type(Quaternary P(4VP -co-AM), QPVA) has been synthesized,which have different cationic degree and molecular weight respectively. This paperinvestigated mainly the antibacterial property of QPVA using Escherichia Coli asdisease-leading bacterium, examined influence of various factors on the antibacterial property,such as cationic degree, molecular weight and pH value with the method of plate countinglive bacterium, and studied the antibacterial mechanism of QPVA by using the method ofmeasuring the activity of β-D-galactosidase and TTC-DHE. Then micrometer-sized silica gelwas modified chemically by using γ-methacryloxypropyl trimethoxysilane (MPTMS) ascoupling agent, and double bond was introduced onto silica gel particle surface. Afterwardsboth solution polymerization method and dispersion polymerization method were adopted,grafting polymerization of polystyrene on silica surface was performed, and the effect ofpolymerization method on grafting degree was examined mainly. Finally micrometer-sizedsilica gel , used as the carrier of insoluble antibacterial material ,was modified chemically byγ-methacryloxypropyl trimethoxysilane (MPTMS) ,and double bond was introduced ontosilica gel particle surface. With the dispersion polymerization method, graftingcopolymerization of 4-vinyl pyridine and acrylamide on silica surface was performed. Thenthe copolymer on silica surface was quaternarized by using benzyl chloride and sulphate ofdimethyl, and a series of grafting cationic polyacrylamide of quaternary pyridine salt-type onsilica surface (Quaternary P(4VP -co-AM)/SiO2, QPVA/SiO2) has been synthesized, whichhave different grafting degree. This paper investigated mainly the antibacterial property ofQPVA/SiO2 using Escherichia Coli as disease-leading bacterium, examined influence ofvarious factors on the antibacterial property, such as grafting degree and the quaternarizedmethods with the method of plate counting live bacterium, and studied the antibacterialmechanism of QPVA/SiO2 by using the method of measuring the activity ofβ-D-galactosidase and TTC-DHE. The experimental results are as follows:(1)cationicpolyacrylamide of quaternary pyridine salt-type possesses excellent antibacterial property.The higher cationic degree of QPVA is, the stronger antibacterial property is. In certain rangeof molecular weight, the higher molecular weight of QPVA, the better antibacterial effect is.The isoelectric point of E.Coli protein is probably pH=4.4.The greater pH value is, the betterantibacterial effect of QPVA is as pH>4.4, and antibacterial ratio remain nearly constant aspH>5.3. Whereas as pH<4.4, the apparent antibacterial ratio increases with the decrease ofpH value, and the phenomenonis probably resulted in by the cooperation of effect of QPVAand action of H+ ions on microbe. The antibacterial effect of QPVA is based on sterilizationaction certainly and is not only a restraining action;(2)the percentage of the graftingpolymerization reaction, which occurs on the interface between silica particle and solutionand is a king of heterogenetic reaction, depends on the amount of the double bondimmobilized on the silica particle surface, and under certain condition, the greater the amountof the double bond on the silica particle surface, the higher the grafting degree. Comparedwith solution polymerization method, dispersion polymerization method has higher graftingpolymerization rate and grafting degree, and the grafting degree can get up to 47% because ofsmaller kinetic barrier than solution polymerization. Except polymerization method, there stillare other factors, such as the concentration of monomer, used amount of initiator, temperatureand so on. For dispersion polymerization system, the property of solvent, the property ofdispersant and its used amount also influence the grafting degree;(3)QPVA/SiO2 possessesexcellent antibacte-rial property, and that the higher grafting degree of QPVA/SiO2 is, thestronger antibacterial property is;The antibacterial effect of QPVA/SiO2 is similar to that ofQPVA. Insoluble macromolecular antibacterial has more higher antibacterial activity relativeto smaller molecular antibacterial owing to higher density of antibacterial groups onmolecular chain;Furthermore, this insoluble antibacterial material protects the water frombeing polluted again due to macromolecular antibacterial immobilized on the insolublecarriers.更多还原