AgBr／I纳米粒子乳剂的制备及性能研究

用络合－沉淀法制备了卤化银含量３０ｇ／Ｌ，粒子大小２０ｎｍ以一的ＡｇＢｒ／Ｉ纳米粒子乳剂，研究发现：ＡｇＢｒ／Ｉ纳米粒子表现出较大的表面活性，并由此导致了其乳剂具有比常规乳剂低得多的感光度和高得多的灰雾，乳剂的最佳碘含量增中到了１１％，硫增感对纳粒乳剂没有效果，但硫加金增感表现出有效性。     

壳聚糖/纳米SiO_2杂化材料的研究

在甲醇和乙酸介质中,通过酸酐与壳聚糖反应,合成了水溶性的N-酰化壳聚糖,并将纳米二氧化硅颗粒与N-酰化壳聚糖水溶液经溶胶-凝胶过程,制备了壳聚糖/纳米S iO2杂化材料。通过傅立叶变换红外光谱、元素分析、扫描电镜等方法对杂化材料进行了表征,采用热重分析对杂化材料的热性能进行研究。扫描电镜分析结果表明,杂化材料为纳米尺度的无机S iO2加强化的片状材料,S iO2颗粒分散在材料中,形成均匀的表面;热重分析结果表明,杂化材料的热性能有较大提高。     

核壳结构聚苯乙烯/壳聚糖纳米复合粒子的制备及乳化性研究

采用简单的模板法制备了以壳聚糖为壳层、聚苯乙烯粒子为核的核壳结构纳米复合粒子PS/CS,用FTIR、SEM和TEM对其进行表征,结果表明,形成的粒子具有核壳结构,且粒径均一。以液体石蜡为油相,考察了PS/CS核壳结构粒子的乳化性能。当粒子浓度为1.0%就可以获得具有长期稳定性的乳液,并且该粒子的乳化能力不受电解质和pH的影响。     

运用静电纺丝技术制备金/壳聚糖/PVP复合纳米纤维

在加热条件下,以乙酸作为溶剂,用壳聚糖还原氯金酸制备了金纳米粒子。壳聚糖分子还保护了生成的金纳米颗粒,因此壳聚糖既为还原剂又是保护剂。紫外吸收光谱证实了溶液内金纳米粒子的存在。采用静电纺丝技术制备了含有金纳米粒子的壳聚糖/聚乙烯吡咯烷酮(PVP)复合纳米纤维。运用透射电镜(TEM)对纤维的表面形貌及纤维内的金纳米粒子的分布进行了表征。     

壳聚糖/聚乙烯醇/壳寡糖抑菌纳米纤维膜的制备和性能研究

以壳聚糖（CS）为基材,使用静电纺丝的方法制备了搭载壳寡糖（CHOS）的CS/聚乙烯醇（PVA）/CHOS纳米纤维膜,并对纳米纤维膜的微观形貌、结构、抑菌性、亲水性以及溶解性能进行了研究。研究发现：CS/PVA/CHOS纳米纤维膜具备均匀密致的微观形貌;FT-IR测试表明,CHOS以物理混合的形式分散在CS/PVA/CHOS纳米纤维膜中;XRD测试表明,CHOS的加入改变了纳米纤维膜的结晶性,促进了各组分之间的相容性;水接触角测试表明纳米纤维膜具备良好的亲水性,在m（CS）：m（PVA）：m（CHOS）=20：80：10时,CS/PVA/CHOS纳米纤维膜的接触角相比于m（CS）：m（PVA）=20：80的CS/PVA纳米纤维膜由59.8°下降到37.5°;抑菌性能和溶解性能测试表明,m（CS）：m（PVA）：m（CHOS）=20：80：10时的CS/PVA/CHOS纳米纤维膜相比于未搭载CHOS的CS/PVA纳米纤维膜,抑菌性提升了38.9%,溶解率提升了38.6%。     

纳米尺度AgBr/I乳剂颗粒的光电子衰减行为

本文以鱼明胶为保护介质,在不同的鱼明胶 溴化银比值下,采用双注法制备AgBr/I纳米颗粒乳剂,以TEM观测颗粒形态,据此统计得出该乳剂中AgBr/I纳米颗粒平均粒径(d)及粒径分布系数(|±σ|/d).鱼明胶 溴化银比值在0.31g/mmol—0.62g/mmol范围内,颗粒平均粒径仅有微小变化,但粒径分布系数随该比值的增大而减小,表明颗粒均一性提高.采用微波光导法对该纳米尺度AgBr/I乳剂颗粒的光电子衰减过程进行测试,结果表明,纳米尺度Ag Br/I乳剂颗粒的光电子衰减过程为双组分,即初始快衰减和随后慢衰减,其衰减过程皆符合一级动力学规律.该纳米尺度乳剂颗粒光电子寿命较常规乳剂颗粒明显缩短.     

壳聚糖纳米纤维/PMMA复合材料的制备及性能分析

利用壳聚糖(Chitosan)纳米纤维对聚甲基丙烯酸甲酯(PMMA)进行增强改性,通过浸渍法制备Chitosan/PMMA复合薄膜材料,并利用傅里叶红外光谱(FTIR)、场发射扫描电子显微镜(FE-SEM)、热性能分析仪(DMA、TMA)、紫外分光光度计等对其性能进行表征。结果表明,浓碱处理甲壳素能够获得壳聚糖;薄膜的断面呈现明显的层状结构;Chitosan/PMMA复合材料的透光率比纯纤维膜提高了约11%;在PMMA中添加壳聚糖纳米纤维能够显著降低树脂的热膨胀系数(CTE),在20～100℃的范围内,添加60%壳聚糖纳米纤维的复合材料的CTE为33.85×10-6K-1,接近于纯PMMA树脂CTE的1/6;Chitosan/PMMA复合样品的储能模量达到了6 GPa,较纯PMMA增加了2倍。     

壳聚糖改性空心多巴胺纳米复合载体的制备及其性能研究

将多巴胺负载于二氧化硅表面,再用氢氟酸刻蚀二氧化硅得到空心多巴胺纳米粒子,该方法简单易操作。再引入壳聚糖对空心多巴胺进行表面改性,提高复合纳米载体的黏附性和生物相容性。红外谱图分析证明材料中具备多巴胺和壳聚糖的特征峰,扫描电镜图显示纳米粒子粒径为100 nm左右,这种壳聚糖改性多巴胺纳米复合载体结合了高药物包载率和优异的缓释性能,将在生物医药领域应用更广阔。     

壳聚糖纳米粒子改性反渗透膜的制备及性能研究

采用反相乳化法制备了壳聚糖纳米粒子(CSNP),以聚醚砜超滤膜为基膜,将CSNP添加在水相中通过界面聚合方法制备了一系列薄层纳米复合(TFN)反渗透膜,研究了CSNP添加量对TFN膜性能的影响。结果表明,CSNP优化添加质量分数为0.010%,即TFN-10膜对NaCl的截留率达到98.89%,水通量为40.53 L/(m~2·h),远高于TFN-0(TFC)膜的水通量(22.92 L/(m~2·h));且TFN-10膜在48 h的长期运行后,水通量和截留率分别稳定在32.20 L/(m~2·h)和99.07%,稳定性良好;对HA抗污染测试中,通量恢复率为83.67%,总污染率为24.84%,抗污染性能明显优于TFC膜(通量恢复率44.88%,总污染率58.19%)。     

纳米氧化镁抗菌材料的研究进展

纳米氧化镁具有毒性低、耐热性高、环境友好、持久和广谱抗菌等优点,可以克服银系抗菌材料的成本高、易变色、稳定性差、生物毒性的问题,也可以弥补光催化类型抗菌材料抗菌效率低和对紫外光依赖的不足,成为当前抗菌材料领域研究热点。本文从抗菌机理、结构调控和复合材料制备3个方面综述纳米氧化镁抗菌材料的研究进展,介绍活性氧氧化损伤和吸附作用机械损伤两种代表性抗菌机理的研究现状,阐述粒径大小、形貌差异、离子掺杂对氧化镁抑菌活性的影响规律,比较氧化镁-氧化物复合抗菌材料、氧化镁-碳/卤素复合抗菌材料、氧化镁-有机物复合抗菌材料的发展。分析表明制备高抗菌活性氧化镁抗菌材料的关键是控制其颗粒形貌、粒径及其表面缺陷,并增强其产生活性氧能力和吸附作用。     

负载纳米银的埃洛石纳米管/聚醚砜杂化超滤膜的制备

以聚醚砜(PES)为膜材料,N, N-二甲基乙酰胺(DMAc)为溶剂,聚乙烯吡咯烷酮(PVP)和负载纳米银的埃洛石纳米管(Ag- HNTs)为添加剂,采用相转化法制备聚醚砜超滤膜。系统地考察了添加剂(Ag- HNTs)含量对膜性能的影响,并用抑菌圈试验研究了所制膜的抗菌效果。结果表明：硅烷偶联剂KH-792中的甲氧基与HNTs上的羟基成功地发生反应,并且接枝量为0.105g (KH-792)?g -1 (HNTs);改性后的HNTs与Ag成功地发生络合反应,并且络合量近似为0.145g (Ag)?g -1 (HNTs);溶剂中负载纳米银的埃洛石纳米管(Ag- HNTs)所占比例的增加能提高膜的水通量,而截留率保持在95%左右。所制备的膜对大肠杆菌和金黄色葡萄球菌有较强的抑制作用。     

Nanocomposite of chitosan and silver oxide and its antibacterial property

An aqueous emulsion of chitosan nanoparticles encapsulating silver oxide is prepared from silver nitrate and chitosan. The nanoparticles are positively charged with an average diameter of 300 nm. The dried particle has a spherical shape with a 100 nm diameter. The emulsion is applied onto cotton and delivers a durable antibacterial activity against S. aureus and E. coli, after 20 washings. The coefficient of friction of the treated fabric is similar to that of the untreated cotton fabric. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008     

利用二醛木聚糖一锅法制备纳米银抗菌水凝胶

利用二醛木聚糖(DAX)可与羧甲基壳聚糖(CMCS)以及银氨溶液同时反应的特性,即DAX的醛基与CMCS的氨基发生席夫碱反应形成亚胺键,同时,DAX含有的大量醛基与银氨溶液发生银镜反应,在室温条件下很快地还原出银纳米粒子(SNPs),一锅法制备出了具有优异抗菌性能的羧甲基壳聚糖-纳米银抗菌水凝胶。加入生物相容性良好的聚乙烯醇(PVA)并通过冻融法形成了与CMCS互穿的双网络结构,进一步提高了水凝胶的结构稳定性。采用FTIR、热重、TEM、XRD和SEM对DAX,SNPs和水凝胶的形貌、结构进行了表征。结果表明DAX在整个反应中起到了十分有效的双功能作用,成功的与CMCS和PVA发生反应,共同构成了双网络结构的水凝胶,从而提高了水凝胶的力学性能。同时,DAX将银氨溶液中的SNPs还原出来,且粒径在20-80 nm之间,具有较好的分散性,从而显著提高了水凝胶的抗菌性。本文中所制备的水凝胶具有伤口敷料方面的应用潜力。     

Preparation and property of antibacterial filter membrane by coaxial electro-spraying/electrospinning technology

Herein, a novel technology named coaxial electro-spraying/electrospinning was successfully introduced, which can simultaneously prepare nanofibers and nanoparticles. First, the device contains an outer nozzle and an inner nozzle, which combine electrospinning with electro-spraying technology. Then, the polyamide 6 (PA6) was spun to prepare the nanofibers from the inner nozzle, and the silver nanoparticles (Ag NPs) into the PA6 solution were sprayed to prepare the nanoparticles from the outer nozzle. PA6 nanofibers (NFs)/Ag nanoparticles (NPs) antibacterial composite membranes for the filtration of fine particulate pollutants were successfully prepared using coaxial electro-spraying/electrospinning. The microstructure, physical properties, and antibacterial properties of the composite membrane were investigated. The results show that Ag NPs are successfully loaded in situ onto PA6 NFs of approximately 100 nm to form a three-dimensional (3D) structure. The filtration efficiency of the 3D structured filtration membrane reaches 90.98%, compared to only 12.78% for the melt-blown cloth mask filter material when tested with polystyrene microspheres (PS) of 200 nm. The contact angle of the composite membrane decreased from 145.47° to 44.11°, indicating a significant improvement in the hydrophilicity of the membrane. Furthermore, depositing Ag on the surface fibers resulted in an impressive antibacterial rate of 99.75% against Penicillium.     

纳米银的抗菌机理研究进展

纳米银因其高效、广谱、不易产生耐药性、安全性高等优点,成为当前抗菌材料的研究热点之一,但目前对纳米银的抗菌机理仍有不同的认识.本文首先综述了国内外纳米银抗菌机理的研究进展和主要成果,主要从影响细菌生活环境、破坏细菌的细胞壁和细胞膜、抑制DNA复制、抑制酶呼吸作用和抑制其他酶活性5个方面分析了纳米银的抗菌机理.并且纳米银的抗菌过程受多种因素影响,文中详细阐述了纳米银的尺寸分布、形貌以及稳定剂、活性氧、菌种和培养基等因素对纳米银抗菌性的影响.最后指出纳米银的抗菌过程复杂,进一步研究其具体作用方式和机理以及影响抗菌作用的主要因素都将有助于纳米银抗菌材料的广泛应用.     

壳聚糖/明胶抗菌微胶囊的制备及其应用

为了制备用于棉织物天然抗菌整理剂,以绿苋、龙葵和黄柏的复配提取物为芯材,壳聚糖-明胶为壁材,采用复凝聚法制备抗菌微胶囊。研究了乳化剂含量、剪切速度、pH对微胶囊的外观形态及尺寸的影响;借助扫描电子显微镜、傅里叶红外光谱仪等对样品进行表征;将抗菌微胶囊用于棉织物的整理并测试其抗菌性能。结果表明：初乳中乳化剂质量分数为5%、剪切速度为8000r/min、pH为5.7为最佳制备条件,制得的微胶囊尺寸分布在1480～3580nm且热稳定性良好;当微胶囊质量浓度为25g/L,黏合剂质量分数为5%,热烘温度为40℃,整理试样对金黄色葡萄球菌和大肠杆菌的抑菌率分别为89.30%和81.43%,且抑菌效果持久。     

Preparation and antibacterial activity of PET/chitosan nanofibrous mats using an electrospinning technique

The nanofiber deposition method, by electrospinning, was employed to introduce antibacterial activity and biocompatibility to the surface of poly (ethylene terephthalate) (PET) textiles. The polymer blends of PET and chitosan were electrospun on to the PET micro‐nonwoven mats for biomedical applications. The PET/chitosan nanofibers were evenly deposited on to the surface, and the diameter of the nanofibers was in the range between 500 and 800 nm. The surface of the nanofibers was characterized using SEM, ESCA, AFM, and ATR‐FTIR. The wettability of the PET nanofibers was significantly enhanced by the incorporation of chitosan. The antibacterial activity of the samples was evaluated utilizing the colony counting method against Staphylococcus aureus and Klebsiella pneumoniae. The results indicated that the PET/chitosan nanofiber mats showed a significantly higher growth inhibition rate compared with the PET nanofiber control. In addition, the fibroblast cells adhered better to the PET/chitosan nanofibers than to the PET nanofibers mats, suggesting better tissue compatibility. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

高补强水合硅抗菌剂的制备及抗菌效果探讨

我国抗菌产业在短短的几年时间内已成长为一个年产值超700亿元的新产业。迄今为止所报道的无机抗菌剂虽然添加到制品中或多或少有一定的抗菌效果,但在分散性、吸附性及补强性方面均比较弱。本文采用来源较广泛且价格便宜的硫酸与泡花碱在银离子附载情况下以双股流工艺合成一种抗菌率高、加工性好的绿色环保的无机水合硅抗菌剂,具有合成工艺简单,成本低,抗色变性好,同时具有高补强高分散性等优点,对大肠杆菌抗菌率达100%,特别适用于抗菌塑料加工制品等领域。通过研究探讨合成条件对产品外观、性能及抗菌效果的影响,以及添加剂对银离子氧化色变问题的预防,经研究最佳的附载工艺为恒温95℃,恒搅拌速度400r/min,pH值为2,水合硅浆料与附载离子摩尔比为50∶1,添加剂与浆料溶液质量比为0.05%。     

贻贝启发蒙脱石-银/聚乳酸抗菌膜的制备及其性能

受自然界贻贝粘附现象的启发,将聚多巴胺(PDA)作为二次反应平台,绿色合成了一种纳米银(Ag NPs)负载蒙脱石(MMT-Ag NPs)复合抗菌颗粒,通过溶剂挥发法将聚乳酸(PLA)和MMT-AgNPs共混,制备了复合抗菌膜(PLA/PDA/MMT-AgNPs)。利用FTIR、XRD、TEM和TGA对MMT-Ag NPs的物质组成、物相结构、微观形貌、热稳定性进行了测定。对所制备的PLA/PDA/MMT-AgNPs复合抗菌膜的微观形貌、物理性能和抗微生物活性进行了考察。结果表明:PDA成功地对MMT进行了改性,PDA改性的MMT仍保持原来的物相结构,Ag NPs在MMT表面成功负载,负载的质量分数达到12.2%。PLA/PDA/MMT-AgNPs复合抗菌膜的拉伸强度显著增强,与PLA膜相比最高增长了32.6%。由于Ag NPs极强的抗菌作用,仅添加少量MMT-Ag NPs的复合抗菌膜就对大肠杆菌和金黄色葡萄球菌表现出了优异的抗菌作用,抑菌率均达到了95%以上。     

Preparation and characterization of hydrophilic and antibacterial silver decorated silica-grafted-poly(vinylpyrrolidone) (Ag-SiO2-PVP) nanoparticles for polymeric nanocomposites

Hydrophilic antibacterial silver decorated silica-grafted-poly(vinylpyrrolidone) (Ag-SiO₂-PVP) nanoparticles were successfully synthesized in multiple steps. In this regard, silanization of the silica nanoparticles was performed with different concentrations of vinyltrimethoxysilane (VTS) to generate vinyl groups onto the nanoparticles surface. Obtained results showed that by increasing the VTS concentration the amount of vinyl groups on the surface of the silica nanoparticles increased while nanoparticles agglomeration did not occur. Then, poly(vinylpyrrolidone) PVP brushes were grafted onto the silanized silica nanoparticles (SiO₂-VTS) via grafting-through polymerization method to obtain PVP-grafted silica nanoparticles (SiO₂-PVP). Fourier transform infrared spectroscopy, thermal gravimetric analysis, and dynamic light scattering confirmed the successful generation of the vinyl groups and PVP brushes onto the silica nanoparticles. Finally, Ag-SiO₂-PVP nanoparticles were prepared by synthesizing silver nanoparticles onto the SiO₂-PVP nanoparticles to render them antibacterial. Energy dispersive X-ray spectroscopy showed that highest grafting of silver nanoparticles onto the SiO₂-PVP nanoparticles was obtained for the nanoparticles with highest content of vinyl groups. X-ray photoelectron spectroscopy was used to identify the elements and their chemical structure for the synthesized nanoparticles. Plate colony counting method was applied to assess the antibacterial effects of the Ag-SiO₂-PVP nanoparticles which revealed outstanding bactericidal properties of them.