季铵盐修饰有机硅改性聚氨酯的制备与杀菌性能

以制备环境友好型海洋防污涂料为目标,利用自制的双羟基封端剂、2,4,6-三(3-氯丙基)-2,4,6-三甲基-环三硅氧烷和八甲基环四硅氧烷(D4),通过开环共聚得到含氯丙基双羟基封端聚硅氧烷,然后经季铵化反应在聚硅氧烷链上引入具有杀菌性的季铵盐基团,最后通过活性基团羟基与异氰酸酯反应合成聚氨酯材料并进一步对聚氨酯的表面性能与抗菌性能进行了表征。结果表明:季铵盐含量为20%时,聚氨酯不仅具有低表面能特性,而且对革兰氏阳性菌和革兰氏阴性菌的杀菌率都能到达90%以上,而且有机硅分子量相近时,季铵盐含量越高,杀菌性越好,但疏水性越差。     

接枝聚阳离子磁性微球的合成及抗菌活性

共沉淀法合成Fe3O4纳米颗粒,经硅烷偶联剂3-(异丁烯酰氧)丙基三甲氧基硅烷(MPS)表面双键功能化,与季铵盐化(苄基溴化或溴己烷化)甲基丙烯酸二甲基氨基乙酯(DMAEMA)单体自由基共聚,获得可循环利用的聚阳离子接枝的磁性抗菌微球(pQAC-Fe3O4)。颗粒形貌及表面性质通过X射线衍射(XRD)、红外(FT-IR)、动态光散射粒径分析(DLS)、透射电镜(TEM)、热重分析(TGA)等表征。测试pQAC-Fe3O4微球对革兰氏阳性、革兰氏阴性菌及真菌的抗菌活性,结果表明两种具有外磁场响应性的pQAC-Fe3O4颗粒均具有高效广谱杀菌性,且经磁分离回收循环利用10次后对大肠杆菌的杀菌率仍可达95%以上。颗粒杀菌效果不仅与接枝季铵盐基团的多少有关还与季铵盐取代基团有关。     

聚醚砜荷正电超滤膜的制备及对染料的分离研究

采用非溶剂相转化法制备了氯甲基聚醚砜/聚醚砜(CMPES/PES)共混膜,并在其表面进行季铵化改性,制得季铵化聚醚砜荷正电超滤膜。经过元素分析,季铵基团成功地接枝在膜的表面。实验对膜的亲水性能、抗污染性能及对染料的分离性能进行了研究。结果表明:季铵化改性膜的亲水性能和水通量显著提高,通量由原来的177L/m2·h增加到233L/m2·h;且改性膜的总污染指数(Rt)和水通量恢复率(FRR)均显著增大,这说明改性后的膜大大降低了不可逆污染。季铵化膜对碱性染料具有较好的分离效果,其中阿利新蓝(AB)的截留率大于90%。     

界面季铵化交联荷电改性PSf复合膜的构造和分离性能的研究

为在膜表面构造荷电性分离层,本文利用超临界CO_2流体合成聚(苯乙烯-马来酸酐)接枝2-二甲氨基乙胺共聚物,再与1,4-对二氯苄季铵化反应,在PSf膜表面形成季铵盐结构的功能分离层。采用表面红外、扫描电镜、接触角和Zeta电位等对膜表面的化学组成、形貌、水润湿性和荷电性进行表征,研究共聚物浓度对MgCl_2透过性能的影响。改性后,膜表面亲水性增强,存在两个等电点,在p H值为4.5~7.6时,表现为荷正电性,共聚物溶液浓度在0.010%~0.0125%(质量分数)时,0.3 MPa渗透通量为35~40 L/m2·h,对MgCl_2的截留率为60%~75%。结果表明,通过界面季铵化交联能够赋予膜表面一定的荷电性,调整p H值可对不同荷电性的盐进行截留。     

β-C位引入供电子羟基增强季铵化聚砜膜的热碱稳定性

以氯甲基化的聚砜(CMPSf)为基材,与N-甲基二乙醇胺和N,N-二甲基乙醇胺反应,分别制备了β-C具有供电子羟基的N-甲基二乙醇胺季铵化聚砜膜(PSf-MDOH)和N,N-二甲基乙醇胺季铵化聚砜膜(PSf-DMOH)。在60℃、1 mol/L的KOH溶液中浸泡6 h后,β-C具有供电子羟基的PSf-DMOH膜和PSf-MDOH膜的离子传导率略有下降,但仍保持了良好的膜尺寸稳定性,而β-C无羟基的三乙胺季铵化聚砜膜发生破碎,完全丧失膜形态,表明供电子羟基的引入显著提高了膜的热碱稳定性。同时,2种膜的性能比较发现,低离子交换容量(IEC)时,PSf-MDOH膜的离子传导率高于PSfDMOH膜,但随着IEC的升高,PSf-MDOH膜吸水率急剧增加,膜内有效离子浓度下降,离子传导率低于PSf-DMOH膜。     

两亲水溶性阳离子聚电解质研究Ⅱ.聚(苯乙烯-丙烯酰胺)的阳离子季铵化改性

疏水性苯乙烯和亲水性丙烯酰胺共聚,得到两亲聚(苯乙烯-丙烯酰胺)(P(St-Am)).P(St-Am)中-CONH2官能团具有反应性,通过氨交换反应,对P(St-Am)的侧链进行功能化改性,N,N-二甲基丙二胺在乙二醇中和P(St-Am)反应生成聚(苯乙烯-N'-丙烯酰胺基-N,N-二甲基丙二胺).以硫酸二甲酯为季铵化试剂,对上述产物进行季铵化反应,得到硫酸二甲酯季铵化聚(苯乙烯-丙烯酰胺).P(St-Am)及其阳离子季铵化改性产物的结构由IR和1H NMR得到了确证.     

聚偏氟乙烯膜亲水化改性及在酪蛋白分离中的应用

采用化学改性的方法,在KOH/KMnO4体系中对聚偏氟乙烯(PVDF)膜表面进行化学处理,引入羟基等活性基团,并利用甘油水溶液增加膜表面的化学稳定性。分别改变试剂浓度、温度、反应时间等参数,确定最佳反应条件。实验结果表明,改性后的聚偏氟乙烯膜表面接触角减小,亲水性增强。将改性前后的膜分别应用于酪蛋白的分离实验,测定膜通量的衰减,发现改性后的PVDF膜表面的抗蛋白吸附能力有很大程度的提高。     

N-长烷基壳聚糖季铵盐的合成及其抗菌活性研究

先用甲醛-甲酸法(eschweiler-clarke反应)合成N,N-二甲基壳聚糖(DMC),再与溴代烷进行Hoffman烷基化反应制备了N-十二烷基-N,N-二甲基壳聚糖季铵盐(DODMC)和N-十六烷基-N,N-二甲基壳聚糖季铵盐(HDMC),用FT-IR、1 H NMR、EA、TG等对产物进行表征。抗菌实验结果表明所合成产物具有较好的抗菌活性,对革兰氏阳性菌S.aureus的抗菌活性优于革兰氏阴性菌E.coli,抗菌活性随着烷基链长度的增加而增强;产物在pH值=5.5比在pH值=7.2条件下表现出更好的抗菌活性;在碱性及中性条件下,HDMC的抗菌活性随着季铵化度的提高而提高,而在酸性条件下抗菌活性则随着季铵化度提高而降低。     

季铵化壳聚糖-聚乙烯醇阴离子交换膜的性能

碱性直接甲醇燃料电池(ADMFC)具有电极反应速率高,甲醇渗透率低的优点,阴离子交换膜是ADMFC的核心之一.以壳聚糖(CS)和环氧丙基三甲基氯化铵为原料合成季铵化壳聚糖,将其与聚乙烯醇(PVA)共混后制得一系列不同配比的季铵化壳聚糖(QCS)/聚乙烯醇阴离子交换膜,对膜的导电率和甲醇渗透系数进行了测试和分析.结果表明:季铵化壳聚糖与聚乙烯醇有较好的相容性,所制季铵化壳聚糖(QCS)/聚乙烯醇共混膜结构致密均匀,膜的吸水率和溶胀度随季铵化壳聚糖含量增大而减小,离子导电率随季铵化壳聚糖含量增大而提高,80℃时季铵化壳聚糖含量为60%的共混膜导电率最高可达2.5×10-2 S/cm.膜的甲醇渗透系数低于Nafion膜.     

BPPO中空纤维荷电镶嵌膜制备及其蛋白质吸附性能

以季铵化BPPO中空纤维膜为原料,通过sol-gel反应填充巯丙基三乙氧基硅烷(KH580),然后进行氧化,得到同时含有季铵和磺酸基团的杂化荷电镶嵌膜,阴离子交换容量(AEC)和阳离子交换容量(CEC)分别为1.57~1.76mmol/g和1.07~1.24mmol/g.对该膜进行了结构和物化性能的表征,然后进行蛋白质吸附和脱附.结果表明,与基膜相比,荷电镶嵌膜在溶胀度方面有所改进.pH=4、7和8时荷电镶嵌膜对牛血清蛋白(BSA)的吸附量较高,可达到20mg/g以上.在碱性条件下(pH=8),脱附率明显高于基膜,可以达到约95%.由此说明基于BPPO的荷电镶嵌中空纤维膜可以用作吸附材料.     

季铵盐接枝聚膦腈微球的制备及抗菌活性

细菌感染引起的疾病问题在世界范围内引起广泛的关注。抗生素虽然能有效治疗细菌感染,但是不合理的使用及滥用会导致细菌产生耐药性。因此,解决细菌耐药性问题并研发出安全高效的非抗生素抗菌剂显得尤为迫切。通过在生物可降解型环交联型聚(环三膦腈-共-聚乙烯亚胺)微球(PHP)表面上接枝环氧丙基十二烷基二甲基氯化铵(DDEAC),成功制备了环交联型聚(环三膦腈-共-聚乙烯亚胺)接枝季铵盐微球(PHPD)。采用FTIR、XPS、TG、TEM和FESEM对微球的结构与形貌进行了表征分析,并研究了其抗菌活性和细胞毒性。实验结果表明,改性抗菌微球PHPD(50 μg/mL)对大肠杆菌(E.coli)和金黄色葡萄球菌(S.aureus)的抗菌率均达97.3%。复合材料克服了单独使用季铵盐DDEAC材料的高毒性缺陷,并且在实现高效抗菌的同时也具有很好的细胞相容性。因此,本研究对于开发安全高效的纳米抗菌剂具有一定的指导意义。      

电纺制备明胶/壳聚糖/羟基磷灰石/氧化石墨烯抗菌复合纳米纤维的研究

本研究模拟细胞外基质成分与结构, 采用静电纺丝法成功制备出明胶/壳聚糖/羟基磷灰石/氧化石墨烯四元复合纤维。重点考察该体系中物质浓度对复合纤维形貌及抗菌性能的影响。结果表明: 明胶浓度增大会增大纤维的直径, 但浓度过大会出现粘连现象, 其最佳浓度为15~20%; 加入壳聚糖(CS)会出现细纤维分支, 其浓度为1%左右较佳; 增加羟基磷灰石(HA)浓度, 可提高电纺液的导电性, 降低纤维中的珠状物和粘联现象发生, 粒径为12 μm的HA浓度为5%时纤维形态较好; 加入氧化石墨烯后可使纤维形态均匀、光滑。最后对四元复合纤维进行了抗菌性能考察, 发现氧化石墨烯的加入增强了复合纤维的抗菌性。明胶/壳聚糖/羟基磷灰石/氧化石墨烯四元复合纤维对金黄色葡萄球菌和大肠杆菌均具有较好的抗菌效果。     

Antibacterial properties of poly(quaternary ammonium) modified gold and titanium dioxide nanoparticles

We report excellent antibacterial effect induced by amine-functionalized gold and titanium dioxide nanoparticles without external excitations. The idea originates from the excellent antibacterial property of quaternary ammonium salts. The effects of poly(quaternary ammonium) and polyacrylate sodium functional groups as nanoparticle surfactants are compared to show that poly(quaternary ammonium) functional groups are the main cause of the induced antibacterial effect. 99.999% of E. coli can be destructed in 10 minutes by simply mixing bacteria with nanoparticle dispersions. The effect of nanoparticle concentrations on the antibacterial property is evaluated. Time required to significantly suppress bacteria growth is studied. The result indicates that the excellent antibacterial property can be introduced to any nanomaterials by using poly(quaternary ammonium) functional groups as surfactants. The engineered nanoparticles can find enormous applications such as self-cleaning surfaces, waste water treatment, Lab-on-a-Chip devices and many more.     

季铵盐壳聚糖抗菌纸的性能研究

以季铵盐壳聚糖为抗菌剂处理普通成纸,制备了包装用抗菌纸。采用抑菌圈法评价了该抗菌纸对大肠杆菌和金黄色葡萄球菌的抑制效果,研究了季铵盐壳聚糖的浓度对抗菌纸厚度、抗张强度、耐破度和抑菌性能的影响。结果表明,抗菌纸的抗张强度及耐破度均较原纸有所增加,厚度没有明显变化,能满足包装需求,且具有良好的抗菌性能,其抗菌效果随季铵盐壳聚糖浓度的增加而增强,并且相同季铵盐壳聚糖浓度下的抗菌纸对金黄色葡萄球菌的抑菌效果要好于大肠杆菌。     

苯乙烯马来酸酐共聚物的阳离子化改性及其对颜料的分散

以无水乙醇和2,3-环氧丙基三甲基氯化胺(ETA)为改性剂,对苯乙烯马来酸酐共聚物(SMA)进行阳离子化改性,制备出一种高分子阳离子表面活性剂(SMG).通过红外光谱、含氮量以及溶解性测定表明:SMG分子中的酸酐基团已全部开环,部分形成酯键,含氮量增至0.372%,在SMG上成功引入了季铵盐基团.SMG易溶于水,降低表面张力的能力比SMA钠盐差,但对颜料黄14的分散效果较好,可以使颜料的zeta电位提高至 35.4mV.     

可聚合性季铵盐及其共聚物的制备与性能研究

以对氯甲基苯乙烯和十二烷基二甲基叔胺为原料,合成了一种可聚合性季铵盐(PQA),并采用自由基溶液聚合法制备了季铵盐-丙烯腈二元共聚物(PQA-co-AN).用FT-IR、1H-NMR和EA表征了PQA和PQA-co-AN的结构,同时用DSC-TG研究了其热稳定性,并测试其抗菌性能.结果表明,PQA经与AN共聚后,共聚物PQA-co-AN的热稳定性和抗菌性能都比单体PQA有所提高.     

Preparation and antibacterial characteristic of water-insoluble antibacterial material QPEI/SiO<Subscript>2</Subscript>

Polyethyleneimine (PEI) was grafted onto micron-sized silica gel particles via the coupling action of gamma-chloropropyl trimethoxy silane, and grafting particles PEI/SiO(2) was prepared. Then, polymeric reactions of two steps, tertiary amination reaction and quaterisation, were conducted for the grafted PEI. After quaterisation of the grafted polyethyleneimine, a composite particle, QPEI/SiO(2), was obtained. QPEI/SiO(2) is a water-insoluble antibacterial material. In this work, the antibacterial characteristic of QPEI/SiO(2) was mainly investigated using Escherichia coli (E. coli) as a disease-leading bacterium and adopting a colony count method. The effects of quaterisation degree of PEI and pH of the medium on the antibacterial ability of QPEI/SiO(2) were examined. The antibacterial mechanism of QPEI/SiO(2) was explored profoundly by using two enzyme activity determination methods, beta-D-galactosidase activity determination and TTC-dehydrogenase activity determination. The experimental results indicates that the water-insoluble antibacterial material QPEI/SiO(2) possesses strong antibacterial ability, for the bacterial suspension with a concentration of 10(9) CFU/ml, the antibacterial ratio of QPEI/SiO(2) can reach about 100% only with a dosage of 15 g/l and only for a contact time of 10 min. The main factors influencing the antibacterial ratio of QPEI/SiO(2) are the quaterisation degree of the grafted PEI and pH value of the medium. QPEI/SiO(2) with higher quaterisation degree has stronger antibacterial ability. In a certain range of pH value, the higher the pH value of the medium is, the stronger the antibacterial ability of QPEI/SiO(2 )is. Enzyme activity determination results show that the antibacterial mechanism of the water-insoluble antibacterial material QPEI/SiO(2) is based on a sterilization process and not only is a bacteriostasis action.     

Preparation of polyurethane cationomer nanofiber mats for use in antimicrobial nanofilter applications

In this study, polyurethane cationomers (PUCs) containing different amounts of quaternary ammonium groups were synthesized and successfully electrospun into non-woven nanofiber mats for use in antimicrobial nanofilter applications. The PUCs showed very strong antimicrobial activities against Staphylococcus aureus and Escherichia coli. The average diameters of the electrospun PUCs fibers decreased with increasing quaternary ammonium group content due to the increased charge density of the PUC solutions. The PUC nanofibers showed adhesion between nanofibers with various bonding sites, yielding mats with a film-like character and structural integrity.     

Preparation of antimicrobial wound dressings via thiol–ene photopolymerization reaction

Preparation of poly (urethane-acrylate) based wound dressings with the ability to boost self-healing of skin tissue through physical protection and maintaining hygiene and moist environment over wounded area is described in the present work. The dressings were prepared via a visible-light induced thiol–ene photopolymerization reaction of a mixture consisting methacrylate urethane prepolymers with hydrophilic and hydrophobic backbones, a quaternary ammonium salt containing methacrylate monomer as an antimicrobial agent, hydroxyethyl methacrylate as reactive diluent and a tetra-functional thiol molecule as a transfer agent. The prepared dressings were characterized and their performance as wound dressings were evaluated through measuring their equilibrium water absorption (EWA), water vapor transmission rate (WVTR), mechanical, and biological properties. Based on recorded data, the optimized dressing formulation had suitable tensile strength even at fully hydrated state and it could preserve the appropriate moist environment by balanced EWA and WVTR ratio. MTT assay confirmed proper cytocompatibility of those dressings containing optimized concentration of quaternary ammonium salt containing monomer (20 wt% or less). Examination of antibacterial activity against different Gram positive, Gram negative bacteria and a fungal strain revealed a complete killing ability for those dressings containing at least 20 wt% of quaternary ammonium salt containing monomer.