O-季铵盐-N,N-双长链烷基壳聚糖的制备及其性能

在合成O-季铵化壳聚糖的基础上,再进行N,N-双烷基化改性,得到O-季铵盐-N,N-双烷基壳聚糖.用FTIR、1H NMR、EA等手段对产物的结构进行表征,并对其溶解性能和表面性能进行研究.实验结果表明:这种新型双亲性壳聚糖季铵盐与N,N-双烷基壳聚糖相比,水的表面接触角降低,亲水性能明显提高;产物除可溶于氯仿与四氢呋喃外,还可溶于N,N-二甲基甲酰胺和冰乙酸中,表现出更明显的双亲性.     

糠醛改性O-季铵化壳聚糖衍生物的合成及其抗菌性能

在制备水溶性较好的O-季铵化壳聚糖基础上,进一步与糠醛反应制备O-季铵化-N-呋喃亚甲基壳聚糖席夫碱及还原产物O-季铵化-N-呋喃亚甲基壳聚糖衍生物,用FTIR、1H NMR、EA（元素分析）、TG（热重分析）对产物进行表征。测定产物的最低抑菌浓度和抑菌率,并与O-季铵化-N-苯亚甲基壳聚糖席夫碱的抑菌效果进行比较。结果表明,产物对革兰氏阳性菌S.aureus的抗菌效果优于革兰氏阴性菌E. coli,在pH值5.5的条件下抗菌效果优于pH 值7.2。并且O-季铵化-N-呋喃亚甲基壳聚糖的抗菌效果>O-季铵化-N-呋喃亚甲基壳聚糖席夫碱>O-季铵化-N-苯亚甲基壳聚糖席夫碱 > O-季铵化-壳聚糖。研究表明,含呋喃杂环的壳聚糖衍生物的抗菌活性明显优于不含杂环的壳聚糖衍生物。     

季铵化/磺化壳聚糖的制备及其抗生物被膜活性

合成了N-(2-羟丙基-3-甲基氯化铵)壳聚糖（HTCC）、N,N,N-三甲基壳聚糖（TMC）和N-(2-羟丙基磺酸钠)壳聚糖（HSCS）。采用红外光谱、核磁共振氢谱、元素分析对产物的结构进行表征，分别比较不同结构的壳聚糖季铵盐（HTCC和TMC）以及相似结构的壳聚糖季铵盐和壳聚糖磺酸盐（HTCC和HSCS）的抗菌活性和抗生物被膜活性。实验结果发现，将壳聚糖的氨基直接季铵化得到的壳聚糖季铵盐（TMC）的抑菌率和生物被膜清除率要优于接枝季铵化得到的壳聚糖季铵盐（HTCC），季铵化壳聚糖（HTCC）的抗菌活性和抗生物被膜活性要优于磺化壳聚糖（HSCS）。0.5mg/mL的TMC对E. coli和S. aureus的抑菌率分别为93.0%和100%。TMC在1/2MIC浓度时对E. coli和S. aureus的生物被膜形成抑制率分别为51.4%和41.5%。2.5mg/mL的TMC、HTCC和HSCS对E. coli的生物被膜去除率分别为49.1%、48.6%和21.2%，对S. aureus的生物被膜的去除率分别为85.1%、82.7%和81.8%。     

N-长烷基壳聚糖季铵盐的合成研究

目的:壳聚糖具有抗菌性、絮凝性、止血性等各种特殊性质,再加上其结构的特殊性,研究其结构同时具有氨基和羧基这一性质,合成了化学修饰的壳聚糖季铵盐[1]。方法:在壳聚糖的结构式中发现其含有特殊基团-羟基和氨基,由于其含有羟基的存在而使得它的氢键功能更强。但是,由于壳聚糖具有特殊的氨基,可以与烯酸发生反应,借助这一特性,可以合成壳聚糖的衍生物[2]。结果:壳聚糖在酸性条件下,在甲醛做为催化剂的反应中,合成了N,N二甲基壳聚糖季铵盐,然后和溴代烷在催化剂的作用下发生Hoffman反应,从而生成N-长烷基壳聚糖季铵盐。结论:通过以壳聚糖为原料,经过N-烷基化反应、水解反应、羧甲基化反应,再干燥得到相对分子量不同的壳聚糖季铵盐.发现其具有较高的合成收率和水溶性;另外,合成的壳聚糖季铵盐质量高,反应时间快,而且节省成本,有效提高了其化学合成环境。     

O-季铵化低聚壳聚糖芳香醛席夫碱衍生物的制备及其抑菌活性

以低聚壳聚糖为对象,苯甲醛、水杨醛、香草醛为改性试剂,设计合成了一系列O-季铵盐低聚壳聚糖芳香醛席夫碱衍生物。产物元素分析发现其席夫碱取代度接近100%,电位滴定确定产物的季铵盐接枝率在35%左右。抑菌活性研究表明,合成的各种O-季铵盐低聚壳聚糖芳香醛席夫碱衍生物抑菌活性明显增强,活性大小依次为香草醛改性物水杨醛改性物苯甲醛改性物低聚壳聚糖。抑菌活性构效关系分析表明,低聚壳聚糖通过芳香醛席夫碱改性引入了酚羟基抑菌活性中心,但酚羟基的抑菌活性受空间位阻影响较大。     

季铵盐改性壳聚糖微球对含铬废水的吸附性能

用2,3-环氧丙基三甲基氯化铵对壳聚糖进行改性得到壳聚糖季铵盐,进一步通过乳化交联法合成壳聚糖季铵盐微球,采用傅里叶变换红外光谱（FT-IR）、差热热重分析（TG-DTG）、X-衍射衍射（XRD）和扫描电镜（SEM）对其进行表征分析。此外,研究了壳聚糖季铵盐的浓度、油水比、交联剂用量对合成的壳聚糖季铵盐微球吸附Cr(Ⅵ)性能的影响,并考察了重铬酸钾初始浓度、pH值、壳聚糖季铵盐微球添加量对Cr(Ⅵ)吸附效果的影响。结果表明：HACC浓度为0.8%(w/V)、油水比为8∶1、壳聚糖季铵盐与交联剂质量比为1.64的条件下,可以制备出球型圆整、分散性好的壳聚糖季铵盐微球。在酸性条件和较低浓度的重铬酸钾均有利于壳聚糖季铵盐微球对Cr(Ⅵ)的吸附。     

新型两性壳聚糖衍生物的制取及应用研究

用氯乙酸和2,3-环氧丙基三甲基氯化铵对壳聚糖进行改性,采用不同反应条件制备了一系列不同取代度的O-羧甲基-N-羟丙基三甲基氯化铵壳聚糖。通过红外光谱对结构进行表征,IR谱图分析证实羧甲基以0位上为主,季铵盐阳离子基以N位上取代为主。研究了产物的取代度、吸湿保湿性、抗菌性、pH稳定性及与表面活性剂的配伍性,结果表明具有良好的吸湿保湿性。     

羧甲基壳聚糖季铵盐絮凝剂的合成与性能研究

先用碘甲烷对壳聚糖(CTS)进行改性,合成具有水溶性的N,N,N—三甲基壳聚糖季铵盐(TMC),然后用一氯乙酸对TMC改性,合成羧甲基壳聚糖季铵盐(CMTMC)。用红外吸收光谱对所合成的物质进行表征,证明CMTMC已被成功合成。用CMTMC对湖水进行絮凝实验,考察絮凝剂加入量、pH、搅拌时间等因素对CMTMC的絮凝效果的影响,实验结果表明:最佳投加量为60mg/L,pH=6.86搅拌时间为慢速搅拌20min,絮凝效果可以达97%以上。     

松香-壳聚糖基梳型离子型高分子表面活性剂的制备及性能研究(摘要)

<正>以脱氢枞胺为原料首次合成了3-氯-2-羟丙基脱氢枞基氯化铵(CHPDMDHA)和烯丙基二甲基脱氢枞基氯化铵(ADMDHA),并创新提出以CHPDMDHA和ADMDHA作为活性季铵盐对壳低聚糖(LWCTSs)、N-羧甲基壳聚糖(N-CMC)、N,O-羧甲基壳聚糖(N,O-CMC)、N-羧乙基壳聚糖(N-CEC)和N,O-羧乙基壳聚糖(N,O-CEC)进行改性,分别得到了CHPDMDHA接枝壳低聚糖(CHPDMDHA-g-LWCTSs)、CHPDMDHA接枝羧烷基壳聚糖(CHPDMDHA-g-CACTSs)、ADMDHA接枝壳低聚糖(ADMDHA-g-LWCTSs)和ADMDHA接枝羧烷基壳聚糖(ADMDHA-g-CACTSs)等4个系列松香改性壳聚糖类梳型高分子表面活性剂。采用FT-IR、NMR、元素分析等手段表征了产物结构,并研究了所合成化合物的     

壳聚糖季铵盐对高岭土悬浮液的絮凝处理

介绍了以3-氯-2-羟丙基三甲基氯化铵(CTA)为改性剂接枝改性壳聚糖,制备了2-羟丙基三甲基壳聚糖季铵盐。用其处理高岭土的悬浮液,讨论了沉降时间、壳聚糖季铵盐的用量、pH值对高岭土悬浮液絮凝效果的影响。结果表明,当沉降18 min,壳聚糖季铵盐添加量为8 mg/L,pH=4时,絮凝效果最好,污水的浊度值可降至1.2。     

海因改性N-季铵化壳聚糖衍生物的合成及其抗菌性能

在酸性条件下,以壳聚糖与环氧季铵盐为原料反应得到水溶性良好的产物N-(2-羟丙基三甲基氯化铵)壳聚糖(HTCC),再用实验室自制的环氧海因改性,得到O-羟丙基(5,5-二甲基海因)-N-(2-羟丙基三甲基氯化铵)壳聚糖衍生物(GH-HTCC),用 FTIR、¹H NMR、UV-VIS和EA 等对产物进行表征。抗菌实验结果表明,产物对两种菌种都有一定的抗菌活性,对金黄色葡萄球菌的抗菌活性优于大肠杆菌;GH-HTCC的抗菌活性优于HTCC,并随环氧海因取代度的增加而增强;低浓度的乙二胺四乙酸(EDTA)增强了HTCC和GH-HTCC的抗菌活性,而高浓度的EDTA在一定程度上抑制了二者的抗菌活性。     

O-一氯均三嗪-N,N,N-三甲基壳聚糖的合成及其在羊毛织物抗菌中的应用

采用甲醛甲酸法合成N,N,N-三甲基壳聚糖（TMC）,再用三氯均三嗪与TMC反应,合成带有可与纤维反应的水溶性O-一氯均三嗪-N,N,N-三甲基壳聚糖（MCT-TMC）。采用FTIR、XRD、热重和元素分析等对产物进行表征,并测试其抗菌性能。将产物对羊毛织物进行抗菌整理,研究整理时间和浓度等工艺条件对抗菌性能的影响。结果表明,TMC和MCT-TMC具有较好的抗菌性能;将其用于羊毛织物抗菌整理的最佳工艺条件为：整理时间60min,整理浓度分别为3%（owf）和2%（owf）;经TMC整理的织物对E.coli和S.aureus的抑菌率分别为97.8%和99.2%,MCT-TMC整理的织物对E.coli和S.aureus的抑菌率分别为98.6%和99.8%。MCT-TMC整理羊毛织物的耐洗涤性能比TMC有显著提高,洗涤后抑菌率仍达到90%以上。     

β-环糊精接枝壳聚糖-黄连素包合物抑菌性能的研究

通过壳聚糖席夫碱反应合成了β-环糊精接枝壳聚糖,用合成产物对黄连素进行了包合.研究了合成产物、包合物对大肠杆菌、金黄色葡萄球菌和黑曲霉的抑菌作用.结果表明,β-环糊精接枝壳聚糖和包合物的抑菌活性较壳聚糖有显著提高.     

Synthesis and antimicrobial activity of Schiff base of chitosan and acylated chitosan

Chitosan, a biocompatible, biodegradable, nontoxic polymer, is prepared from chitin, which is the second most naturally occurring biopolymer after cellulose. Schiff base of chitosan, sorbyl chitosan, and p‐aminobenzoyl chitosan were synthesized working under high‐intensity ultrasound and their antimicrobial properties were analyzed against Escherichia coli, Staphylococcus aureus, and Aspergillus niger. The structures of the derivatives were characterized by FTIR spectroscopy and elemental analysis. The results of antimicrobial activities indicated that the antimicrobial activities of the derivatives increased with increasing the concentration. The antibacterial activity of schiff base of chitosan against E. coli was stronger, while acylated chitosan had better inhiting effect on S. aureus than others. It was also found that the antifungal activities of the derivatives were stronger than that of chitosan, and schiff base of chitosan was obviously superior to acylated chitosan. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Manufacture and properties of chitosan/N,O‐carboxymethylated chitosan/viscose rayon antibacterial fibers

Chitosan/N,O‐carboxymethylated chitosan/viscose rayon antibacterial fibers (CNVFs) were prepared by blending chitosan emulsion, N,O‐carboxymethylated chitosan (N,O‐CMC), and viscose rayon together for spinning. The fibers were characterized by transmission electron microscopy (TEM), differential scanning calorimetry (DSC), and thermal gravimetric analysis (TGA). TEM micrographs showed that chitosan microparticles dispersed uniformly along the oriented direction with the mean size ranging from 0.1 to 0.5 μm. DSC spectra of these fibers showed that no significant change in thermal property was caused by adding chitosan and N,O‐CMC into the viscose rayon. TGA spectra showed that the good moisture retentivity was not affected by the addition of chitosan and N,O‐CMC. Both DSC and TGA suggested that the decomposing tendency of the viscose rayon above 250°C seemed to be weakened by the chitosan. The fibers' mechanical properties and antibacterial activities against Escherchia coli, Staphylococcus aureus, and Candida albicans were measured. Although the addition of chitosan slightly reduced the mechanical properties, the antibacterial fibers' properties were obtained and were found to meet commercial requirements. CNVF exhibited excellent antibacterial activity against E. coli, S. aureus, and C. albicans. The antibacterial activity increased along with the chitosan concentration and was not greatly affected by 15 washings in water. Scanning electron microscopy (SEM) was used to observe the morphology of bacteria cells incubated together with the antibacterial or reference fibers. SEM micrographs demonstrated that greater amounts of bacteria could be adsorbed by the antibacterial fiber than by the reference fiber; these bacteria were overwhelmingly destroyed and killed. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2049–2059, 2002; DOI 10.1002/app.10501     

Preparation, characterization and antimicrobial activity of chitosan/layered silicate nanocomposites

Chitosan/layered silicate nanocomposites with different ratios were successfully prepared via solution-mixing processing technique. Unmodified Ca²⁺-rectorite and organic rectorite modified by cetyltrimethyl ammonium bromide were used. Their structures were characterized by XRD, TEM and FT-IR techniques. The results showed that chitosan chains were inserted into silicate layers to form the intercalated nanocomposites. The interlayer distance of the layered silicates in the nanocomposites enlarged as its amount increased. When the weight ratio between chitosan and organic rectorite was 12:1, the largest interlayer distance of 8.24 nm was obtained. However, with further increase of its amount, the interlayer distance of the layered silicates in the nanocomposites reduced. In vitro antimicrobial assay showed that pristine rectorite could not inhibit the growth of bacteria, but chitosan/layered silicate nanocomposites had stronger antimicrobial activity than pure chitosan, particularly against Gram-positive bacteria. With the increase of the amount and the interlayer distance of the layered silicates in the nanocomposites, the nanocomposites showed a stronger antibacterial effect on Gram-positive bacteria, while the nanocomposites showed a weaker antibacterial effect on Gram-negative bacteria. The lowest minimum inhibition concentration (MIC) value of the nanocomposites against Staphylococcus aureus and Bacillus subtilis was 0.00313% (w/v), and the relative inhibition time (RIT) against B. subtilis with concentration of 0.00313% (w/v) was >120 h.     

Antiviral activity of silver nanoparticle/chitosan composites against H1N1 influenza A virus

Silver nanoparticle (Ag NP)/chitosan (Ch) composites with antiviral activity against H1N1 influenza A virus were prepared. The Ag NP/Ch composites were obtained as yellow or brown floc-like powders following reaction at room temperature in aqueous medium. Ag NPs (3.5, 6.5, and 12.9 nm average diameters) were embedded into the chitosan matrix without aggregation or size alternation. The antiviral activity of the Ag NP/Ch composites was evaluated by comparing the TCID₅₀ ratio of viral suspensions treated with the composites to untreated suspensions. For all sizes of Ag NPs tested, antiviral activity against H1N1 influenza A virus increased as the concentration of Ag NPs increased; chitosan alone exhibited no antiviral activity. Size dependence of the Ag NPs on antiviral activity was also observed: antiviral activity was generally stronger with smaller Ag NPs in the composites. These results indicate that Ag NP/Ch composites interacting with viruses exhibit antiviral activity.     

Preparation of O‐carboxymethyl‐N‐trimethyl chitosan chloride and flocculation of the wastewater in sugar refinery

A novel water soluble amphiphilic O‐ carboxymethyl‐N‐trimethyl Chitosan chloride (CMTMC) was synthesized. The structure of this material was characterized by Fourier transform infrared (FTIR) spectroscopy, ¹³C nuclear magnetic resonance (¹³C‐NMR) spectroscopy and X‐ray diffraction (XRD) techniques. The results showed that CMTMC had been successfully prepared. To determine the flocculation performance of the synthesized amphiphilic polymer, a comparison was made among Chitosan (CS), N‐trimethyl chitosan chloride (TMC), O‐carboxymethyl chitosan (CMC), and CMTMC on the turbidity and COD removal efficiency of 1% (v/v) wastewater in sugar refinery suspensions at pH 5.0, 7.0 and 9.0 at a dosage range of 0–8 mg/L. The results showed that the water soluble amphiphilic polymer CMTMC, which contains longer polymer anion and polymer cation, had the best performance not only in turbidity removal but also in COD removal on sugar refinery wastewater. The using of CMTMC as a flocculant to treat wastewater in sugar refinery was actually more effective than CS, CMC, and TMC. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010