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1.
车秋凌  辛梅华  李明春  陈帅 《化工进展》2018,37(3):1098-1104
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.coliS.aureus的抑菌率分别为97.8%和99.2%,MCT-TMC整理的织物对E.coliS.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。  相似文献   

2.
采用反应活性强和交联条件温和的二乙烯基砜为交联剂,制备了N,N,N-三甲基壳聚糖季铵盐水凝胶(TMCG)并研究了TMCG的溶胀行为、水的状态和分布以及力学性能等。结果表明,TMCG在水中溶胀迅速,平衡溶胀度达40倍,并且具有离子响应性;水分子在TMCG中以自由水、可冻结的结合水和非冻结的结合水三种形式存在,其非冻结的结合水含量随交联剂浓度的增加而增大。TMCG具有良好的力学性能,拉伸强度达13.8 MPa,断裂伸长率达135.3%。  相似文献   

3.
A series of modified chitosan derivatives 14 has been synthesized. Modification process of chitosan was achieved through a sequence of four reactions starting by protection of its amino group with benzaldehyde (derivative 1), followed by reaction with epichlorohydrine (derivative 2), then reaction with benzhydrazide (derivative 3), and finally restoring the free amino groups on the chitosan by removing of benzaldehyde molecules (derivative 4). These four derivatives were characterized by elemental analyses, FTIR, and X-ray. The four chitosan derivatives showed better antibacterial and antifungal activities than that of chitosan. Derivative 4 exhibited the highest antimicrobial activity relative to the other derivatives.  相似文献   

4.
容学德 《化工进展》2014,33(4):1006-1009
碱性条件下将壳聚糖脱晶,利用红外光谱(FT-IR)对其结构进行了确证,并以N,N-二甲基甲酰胺和无水乙醇为介质,将脱晶壳聚糖与马来酸酐在室温条件下摩尔比按1∶1进行酰化反应18 h,合成了取代度DS=63%的N-马来酰化壳聚糖。由FT-IR测试的结果表明了马来酸酐成功接到壳聚糖分子的氨基上。将制备的N-马来酰化壳聚糖在室温下分别与氯化锌、氯化铜反应6 h,制得N-马来酰化壳聚糖与二价锌离子和二价铜离子的配合物。采用FT-IR及电子顺磁共振光谱(EPR)对配合物的结构进行表征。结果表明,N-马来酰化壳聚糖在温和条件下能与Cu(Ⅱ)、Zn(Ⅱ)形成配位化合物,N-马来酰化壳聚糖中的氨基与羧基共同参与配位。  相似文献   

5.
A novel macrocyclic polyamine derivative of chitosan was synthesized by a reaction between chitosan and epoxy‐activated macrocyclic polyamine. The copolymer that is obtained contains amino functional groups in its skeleton and secondary amine and more polar hydroxyl groups. Four types of analyses were used to characterize the chemical modifications of the chitosan: elemental, FTIR spectra, solid‐state 13C‐NMR, and X‐ray diffraction. The adsorption properties of the macrocyclic polyamine grafted chitosan for Ag+, Cu2+, Co2+, and Cr3+ were also investigated. The experimental results showed that the new macrocyclic polyamine derivative of chitosan has high adsorption capacity and good selectivity for Ag+ in the presence of Ag+, Co2+, and Cr3+. The selectivity coefficients were K = 6.16, K = 14.81, and K = 2.42, respectively. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 924–929, 2003  相似文献   

6.
制备了O,O-双十二酰化-N,N,N-三甲基壳聚糖季铵盐(DATMC),用FTIR、EA和1H NMR对产物进行表征,并研究其与胆固醇(CH)的混合单分子膜性质。结果表明:DATMC在氯仿、THF和DMF中具有良好的溶解性。随着胆固醇含量的增加,DATMC /CH混合分子膜的崩溃压和极限分子占据面积均减小;在任何膜压下,体系的超额自由能ΔGexc< 0,说明DATMC与CH二者处于混溶状态。并且XCH=0.8时,ΔGexc最小,此时相容性最好,体系最稳定。实验结果表明,调整胆固醇的含量可以改变混合单分子膜的性质。  相似文献   

7.
A series of water‐soluble chitosan derivatives, carrying galactose residues, were synthesized by using an alternative method in which the galactose groups were introduced into amino groups of the derivatives. First, hydroxyethyl chitosan (HECS) and hydroxypropyl chitosan (HPCS) were synthesized under alkaline conditions by using chitosan and propylene or chitosan and ClCH2CH2OH as the starting materials, respectively. Then lactobionic acid was added into the systems so as to form galactosylated HECS (Gal‐HECS) and galactosylated HPCS (Gal‐HPCS) with substitution degrees of 53 and 47%, respectively. Lactosaminated HPCS (Lac‐HPCS) and Lactosaminated HECS (Lac‐HECS) were obtained with substitution degrees of 42 and 38%, respectively, by the reductive amination of the mixtures of lactose and HECS or lactose and HPCS with potassium borohydride present in the reaction. The chemical structures of new chitosan derivatives were characterized by FTIR, 1H NMR, 13C NMR, and elemental analysis. Some physical properties were also analyzed by wide angle X‐ray diffraction (WAXD) and differential scanning calorimetry (DSC). The novel chitosan derivatives carrying galactose residues may be used as additives for hepatic targeting delivery. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2161–2167, 2005  相似文献   

8.
Two new chitosan azacrown ethers bearing hydroxyl groups (CTS‐DH and CTS‐DO) were synthesized by the reaction of 3‐hydroxyl‐1,5‐diaza‐cycloheptane and 3‐hydroxyl‐1,5‐diaza‐cyclooctane with epoxy‐activated chitosan. Their structures were characterized by elemental analysis, infrared spectra analysis, and X‐ray diffraction analysis. The adsorption and selectivity properties of the hydroxyl azacrown ethers chitosan derivatives for Ag+, Cr3+, Cd2+, and Pb2+ were also investigated. The experimental results showed that the two novel chitosan azacrown ethers have good adsorption capacity for Ag+, and also showed that the grafted chitosan azacrown ethers have high selectivity for the adsorption of Ag+ in the presence of Pb2+ and Cd2+. The selectivity coefficients of CTS‐DH and CTS‐DO were K = 21, K = 42, K = 20.5, K = 41, respectively. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1793–1798, 2001  相似文献   

9.
The synthesis of chitosan methylcarbamate (ChMC) and ethylcarbamate (ChEC) is described by using a new methodology. Polymers with substitution degrees up to 63% for ChEC and 68.5% for ChMC were obtained. Derivatives with lower substitutions were acid soluble but those with higher ones were completely insoluble. This could be due to the loss in hydrophilic sites when the substitution degree increases. The reaction conditions and degree of substitution obtained for both derivatives were also described. A complete chemical characterization was carried out by spectroscopic techniques. The thermal degradation of chitosan and derivatives were studied in the range 25–500°C and both derivatives were shown to be thermally less stable than chitosan. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2742–2747, 2002  相似文献   

10.
A polyurethane–chitosan (PU–CH) coating was synthesized from castor-oil-based PU prepolymer and highly deacetylated and depolymerized chitosan. The films cast with the coating were used for the characterization. X-ray photoelectron spectroscopy, a surface-sensitive technique, indicated the chemical bonding between the chitosan and PU prepolymer as well as the enrichment of chitosan on the surface of the film PU–CH. Electron spin resonance (ESR) spectroscopy using the nitroxyl radical 4-hydroxy-2,2,6,6-tetramethyl piperidine-1-oxyl (4-hydroxy-TEMPO) as a reporter group was used to study the chain mobility in the film PU–CH. It was observed that T50G of the probe and the first glass transition temperature (Tg1) of the film PU–CH were 10 and 18°C higher than those in the PU film, respectively, and the activation energy (27.0 kJ mol−1) of tumbling for the probe covalently bonded with PU–CH was 12.8 kJ mol−1 higher than that of the probe with the film PU. It suggests that the molecular motion in the PU–CH was restricted by grafted and crosslinked interpenetrating polymer networks (IPNs). The results of the differential thermal analysis and thermogravimetric analysis proved that the thermostability of the film PU–CH was significantly higher than that of the film PU, and the Tg1 value is in good agreement with that calculated from ESR. It could be concluded that the IPNs resulted from the chitosan grafting and crosslinking with PU exist in the film PU–CH. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 1321–1329, 1998  相似文献   

11.
Para-biguanidinyl benzoyl chitosan hydrochloride (p-BGBC) is prepared with chitosan (CTS) and para-biguanidinyl benzoyl chloride, which is synthesized by acidchloride reaction of para-biguanidinyl benzonic acid hydrochloride (p-BGBA), as starting material in the medium consisted of MeSO3H and dimethyl sulfoxide (DMSO). Structure of p-BGBC is characterized by FT-IR, 1H NMR and gel permeation chromatography (GPC), and its antimicrobial activities are evaluated against a Gram-negative bacterium Escherichia coli (E. coli) and a Gram-positive bacterium Staphylococcus aureus (S. aureus). Compared with CTS hydrochloride, p-BGBC has much stronger antimicrobial activities, which increase with the increase of its degree of substitution (DS) of guanidinylation. When the DS of p-BGBC achieves or exceeds 36.8%, its antibacterial activities against the tested bacteria are higher than that of Bromo-Geramium. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

12.
新型冠醚交联壳聚糖的合成   总被引:13,自引:3,他引:13  
利用壳聚糖C2位上活泼氨基与苯甲醛反应,制得了保护氨基的Schiff碱壳聚糖(简称CTB);再将合成的带有双活性基团的4,4‘-二溴二苯并18-冠-6冠醚与壳聚糖分子的羟基发生反应,得到二苯并18-冠-6冠醚交联的Schiff碱壳聚糖(简称CTBD),在酸性条件下使CTBD脱去苯甲醛,制得二苯并18-冠-6冠醚交联壳聚糖(简称CTD)。其主要中间体及产物的结构经红外光谱、质谱、核磁共振动等进行了鉴定。  相似文献   

13.
壳聚糖硫酸盐催化合成富马酸二甲酯   总被引:4,自引:0,他引:4  
以壳聚糖硫酸盐为催化剂 ,用富马酸与甲醇反应合成了富马酸二甲酯 (DMF) ,用正交实验确定了反应条件对DMF收率的影响。最佳工艺条件为 :反应时间为 6h ,甲醇与富马酸的摩尔比为 6∶1 ,催化剂用量为1 0 g ,DMF的最高收率可达 86 0 %。催化剂重复使用实验表明 ,该催化剂对DMF的合成具有较好的催化活性及重复使用性  相似文献   

14.
为了改善疏水缔合聚丙烯酰胺的溶解性以及溶液稳定性,本文采用巯基壳聚糖对疏水缔合聚丙烯酰胺进行改性,红外表征结果说明巯基壳聚糖连接到了聚丙烯酰胺分子链上。对影响壳聚糖改性实验的因素进行分析,实验结果说明,壳聚糖中巯基含量增大、壳聚糖加入量增大以及改性反应温度升高都会造成聚合物分子量降低,当改性反应的反应温度不高于35℃、添加壳聚糖质量不高于单体质量的3%时,得到的改性聚合物分子量满足现场使用要求。对改性聚合物的溶解性及溶液稳定性进行了评价,结果表明,壳聚糖中巯基含量增大及壳聚糖加入量增大对聚合物溶解性及溶液稳定性有明显的改善,聚合物的溶解时间由改性前的150min最多缩短至20min,聚合物溶液黏度保留率由改性前的60%最多提高到90%以上,壳聚糖改性有望弥补疏水缔合聚合物现场使用中的一些不足。  相似文献   

15.
Poly(ethyleneglycol) (PEG)/tartaric acid (TA)‐crosslinked chitosan hydrogel (CPT) films were prepared, and the formation of the PEG/TA‐crosslinked structure was confirmed by Fourier transformed infrared (FTIR), nuclear magnetic resonance (NMR), and scanning electron microscope (SEM) measurements. The thermal properties of the crosslinked films were also determined with thermogravimetric analysis (TGA) and differential scanning calorimeter (DSC) analysis. The swelling properties of the films were investigated at different temperature and pH values. It was found that the swelling ratio increased with the decrease of pH value of the surrounding buffer solutions, amount of PEG, and with the increase of temperature. Swelling behavior of the PEG/TA‐crosslinked chitosan hydrogel films depended on pH and reversible with the temperature. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

16.
The synthesis of a new dihydroxyl mesocyclic diamine grafting chitosan is presented. This derivative is formed by reaction of dihydroxyl azacrown ether with expoxy‐activated chitosan. The obtained copolymer contains amino functional groups in its skeleton and the secondary amine, and more polar hydroxyl groups. Elemental analysis, fourier transform infrared analysis, as well as solid‐state carbon‐13 nuclear magnetic resonance analysis were used to characterize chemical modifications of the chitosan. The adsorption properties of the dihydroxyl mesocyclic diamine grafted chitosan for Ag+, Pb2+, Cd2+, and Cr3+ were studied. The experimented results showed that the novel chitosan derivative has good adsorption capacity and high selectivity for Ag+ in the presence of Pb2+, Cd2+, and Cr3+, and its adsorption selectivity is better than that of chitosan. The selectivity coefficients were K = 12.25, K = 6.12, and K = 0.52, respectively. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2677–2681, 2002  相似文献   

17.
Azacrown ether chitosan (CTSC) was synthesized by the reaction of chitosan with N‐allyl benzo 15‐crown‐5 crown ether. Azacrown ether crosslinked chitosan (CCTSC) was prepared by the crosslinked reaction of CTSC and epichlorodydrin. Their structures were confirmed by infrared spectral analysis and X‐ray diffraction analysis. The adsorption properties of CTSC and CCTSC for metal ions were also investigated. The experimental results showed that the two chitosan derivatives not only had a good capacity to adsorb Pd2+ and Ag+ but also was highly selective for Pd2+ and Ag+ in the coexistence system containing other metal ions. At 20°C ± 1°C and pH = 4, the adsorption capacity of CTSC and CCTSC for Pd2+ was 186.1 and 173.1 mg/g, respectively; and for Ag+ was 90.2 and 56.5 mg/g, respectively. The selectivity coefficients were K = 6.99, K = ∞, K = 35.38, K = ∞ for CTSC and K = 10.66, K = ∞, K = 85.45, K = ∞ for CCTSC. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2705–2709, 2006  相似文献   

18.
李玮  李明春  辛梅华 《化工进展》2014,33(4):966-970,987
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。  相似文献   

19.
N,N-双十二烷基化壳聚糖的制备   总被引:2,自引:2,他引:2  
孙晓丽  辛梅华  李明春  苏盛 《化工进展》2006,25(9):1095-1097
以十二烷基磺酸钠为相转移催化剂,通过月桂醛与壳聚糖反应形成Schiff碱,再用NaBH4还原合成N,N—双十二烷基化壳聚糖初产物。利用不同烷基化取代度的壳聚糖在氯仿溶剂中溶解度的差别,对初产物进行提纯,可溶于氯仿的产物的结构经红外光谱、核磁共振和元素分析等方法证明接近为完全N,N-双十二烷基化壳聚糖。  相似文献   

20.
壳聚糖硫酸盐催化合成乙酸仲丁酯   总被引:4,自引:0,他引:4  
刘春生  于杨  刘迪  罗根祥 《化学试剂》2007,29(4):243-244,246
以壳聚糖硫酸盐为非均相催化剂,对仲丁醇与乙酸酐之间的酰化反应进行了研究,考察了催化剂质量、醇酐物质的量比、反应时间对乙酸仲丁酯收率的影响。壳聚糖硫酸盐有着较好的催化活性,当乙酸酐用量为0.1 mol,醇酐物质的量比为1.1,催化剂质量为0.25 g时反应30 min,乙酸仲丁酯收率可达95.6%,且催化剂重复使用5次仍保持较高活性,所得产品无色透明,纯度很高。产品用折光率和红外光谱进行了确证。  相似文献   

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