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1.
To obtain an antibacterial chitosan derivative, composite films of N,O‐Carboxymethyl Chitosan (N,O‐CMCS) and bamboo fiber were prepared. A water‐soluble chitosan derivative‐N,O‐CMCS was synthesized from chitosan with chloroacetic acid in alkaline solution. Composite films with 1–5 wt % N,O‐CMCS content were prepared in NaOH/urea/thiourea solution. The DS of N,O‐CMCS reached 1.70 and the water solubility increased with the increasing of DS. The carboxymethyl group was introduced into chitosan, which led to the decrease of thermal stability and crystallinity. The structural characterization confirmed that N,O‐CMCS was adsorbed on the surface of bamboo fiber. The antibacterial performance of the composite films were enhanced with the increasing of N,O‐CMCS content. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39851.  相似文献   

2.
Cotton fabrics treated with a crosslinking agent, epicholorohydrin, in the presence of chitosan (CEC) provide many possible reactive sites for reactive dyes and antimicrobial properties of the grafted chitosan to the cellulose structure. This process was applied by means of the conventional mercerizing process. The chitosan finishing and durable press finishing of the cotton fabrics occurred simultaneously in the mercerization bath. ECH is expected to react with hydroxyl groups in cellulose and chitosan or with amino groups in chitosan to form alcohol crosslinking by the Belfast process. The fixed chitosan content in the CEC was calculated by the nitrogen percentage of an Elemental Analyzer. The color strength (K/S) of the reactive dyes of the treated cotton fabrics did not significantly change with an increase of chitosan; however, the degree of swelling of the treated cotton fabrics decreased with an increase of chitosan and ECH. These performances were retained through 20 washing and tumble drying cycles. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

3.
4.
Liping Sun  Lihong Fan  Jianhong Yang 《Polymer》2006,47(6):1796-1804
Quaternized carboxymethyl chitosan (QCMC) was prepared from which carboxymethyl chitosan (CMC) was prepared from chitosan first, then N-quaternary ammonium group was introduced by the reaction of CMC with 2, 3-epoxypropyl trimethylammonium. The structures of the derivatives were characterized by FT-IR, XRD, 13C NMR, 1H NMR and gel permeation chromatography. In vitro antimicrobial activities of QCMC were evaluated against Escherichia coli, which is a Gram-negative bacterium, and Staphylococcus aureus, which is a Gram-positive bacterium. In compared with carboxymethyl chitosan (CMC) and quarternary chitosan (QC) of the same degree of substitusion (DS), we found that QCMC has stronger antimicrobial activity. Then we went deep into study of the relationship between their structure and antimicrobial activity, found that the DS of CMC do little effect to their antimicrobial activity, but as the increase of their DS of quaternization or the decrease of their molecular weight, the antimicrobial activity of QCMC become stronger. QCMC was complexed with calcium hydroxide as pulp-cap. Animal experiment results indicated that QCMC can strongly induce reparative dentine formation and showed a better ability in dentin inducing compared with calcium hydroxide.  相似文献   

5.
The chelation between O,N‐carboxymethyl chitosan (ONCMCh) and zinc sulfate in aqueous solution was studied by kinetic experiments and characterized by inductively coupled plasma (ICP) and UV spectrophotometry. The experimental data indicated that the chelating processes were greatly controlled by the reaction conditions (i.e., reaction time, temperature, and Zn2+ ionic and ligand concentrations). The consequence of chelating Zn2+ onto ONCMCh was the formation of complexes with different solubilities. The favorable complexes for ONCMCh‐Zn2+ chelate were at the low zinc ionic and ligand concentrations, as well as at the appropriate temperature. The evidence provided by the kinetic parameters and the changes in zinc concentration by ICP analysis further confirmed the plausible complexing mechanisms. While the formation of water‐soluble products was occasioned by the electrostatic attraction mechanism, the water‐insoluble products were predominantly formed by chelation of Zn2+ with O,N‐carboxymethyl chitosan. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 2246–2253, 2000  相似文献   

6.
Carboxymethyl chitosan sodium (CMCTS) was synthesized by chitosan and chloroacetic acid under an alkali catalyst. Acrylic acid sodium salt and methylacrylic acid sodium salt were grafted onto CMCTS to obtain copolymers with good water solubility. The graft reaction was carried out at 70°C for 2 h, and ammonium persulfate was used as an initiator. The structure changes of chitosan and its derivatives were investigated by the FTIR. The antibacterial activity of chitosan derivatives against Staphylococcus aureus and Escherichia coli were explored by the viable cell counting method. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1357–1361, 2002  相似文献   

7.
壳聚糖及其衍生物含有大量的氨基和羟基,为壳聚糖的改性或者接枝反应提供了活性基团,壳聚糖/羧甲基壳聚糖因特殊的化学结构而使其具有优异的化学性质,如良好的生物相容性、无毒、生物可降解性以及抗微生物活性等性质,因此受到生物工程、医药、食品、化妆品以及其他一些领域的广泛关注,成为近年来研究开发的热点。对壳聚糖/羧甲基壳聚糖及其衍生物在日用化学中的应用进行了综述,并对其发展趋势进行了展望。  相似文献   

8.
Sorption of water vapour by chitosan/carboxymethyl cellulose polyelectrolyte complex membranes prepared at two different pHs was studied. A linear dependence of the water uptake (W) on time was observed for W values lower than 0.5 g of water per gram of membrane. For higher values of W diffusion becomes controlled by the relaxation of the chains, and second-order kinetics is observed. An equation that satisfactorily reproduces this behaviour is proposed. Desorption experiments were carried out at different temperatures and the W versus time curves obtained exhibited the same general pattern and were also adjusted by this equation. The approximate average diffusion coefficients were evaluated at each temperature and the apparent activation energy for the diffusion process is reported.  相似文献   

9.
车秋凌  李明春  辛梅华 《化工进展》2018,37(11):4330-4336
壳聚糖具有良好的抗菌性、吸湿性、反应活性和成纤性,作为新型织物整理剂在纺织产业具有广泛的应用前景。本文综述了近年来壳聚糖及其衍生物在天然织物抗菌、染色、阻燃、防静电、抗紫外和防毡缩等整理中的应用,并就其赋予织物各项性能的机理及影响因素进行讨论。采用对壳聚糖进行改性、与金属化合物的复合使用和对织物表面进行超声、等离子等预处理的方法有利于改善其对织物的整理效果,并对织物的各项物理性能起积极作用。未来壳聚糖基整理剂可在加强某个单一性能的基础上,选择性地引入多个功能性基团,合成符合应用需求的环保型多功能整理剂。  相似文献   

10.
张毅  姜迎雪  张昊 《化工进展》2020,39(7):2810-2816
以三乙胺和环氧氯丙烷为原料,合成醚化剂3-氯-2-羟丙基三乙基氯化铵。以甲壳素为原料通过醚化反应合成了季铵型甲壳素(CCT),再经脱乙酰得到季铵型阳离子改性壳聚糖(CCTS)。采用红外光谱(FTIR)、核磁碳谱(13C NMR)对其化学结构进行了表征,运用黏度法和分光光度法测定了黏均分子量和溶解性等理化性能。采用最小抑菌法对CCTS的抗菌活性进行了测定,得到其对大肠杆菌的最低有效抑菌浓度(MIC)为0.2g/L,优于天然壳聚糖的MIC值。以柠檬酸为交联剂、次磷酸钠为催化剂,用CCTS对兔毛织物进行抑菌整理,考察织物经整理的抑菌效果和耐洗性。经5次洗涤后结果表明,CCTS对大肠杆菌的抑菌率达99.9%以上,抑菌率高于CCT和天然壳聚糖,是一种针对动物毛织物良好的天然高分子长效抑菌整理剂。  相似文献   

11.
Nonwoven polypropylene and cotton fabrics were subjected to plasma pretreatment followed by flash evaporation and radiation crosslinking acrylate polymer coating, which is based on a vacuum deposition, solvent free, process that produces high quality, uniform fabrics with various thicknesses (0.05–5.0 μm). These treated fabrics were then dipped into chitosan, carboxymethyl chitosan, and carboxymethyl chitin solution. These polysaccharides form strong complexes with the modified surface. The antimicrobial activity of these treated samples was then evaluated for their antifungal and antibacterial properties. The antifungal activity for Fusarium oxysporum f. sp. lycopersici, Verticillium albo‐atrum, and Alternaria solani (A. alternata) were examined by the disc plate method. The antibacterial activities of the modified fabrics against Clavibacter michiganensis and Pseudomonas solanacearum were also examined by the viable cell counting method. The inhibition zone of the chitosan covered samples has increased by a factor of 2–3.1 over the original pretreated samples. The chitosan‐modified fabrics showed a good antibacterial activity in killing almost 105 cells/mL within 18–23 h. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

12.
This study examined the possibility of using glyoxal and chitosan in one‐step finishing to impart both durable press performance and antibacterial efficacy on cotton fabrics. Glyoxal treatment provided good wrinkle resistant property and fair antibacterial activity on the finished fabrics, but the loss of breaking strength retention of the finished fabrics was a main problem of this treatment. Chitosan added in the combination of glyoxal and chitosan system also provided comparable results in wrinkle resistant and antibacterial properties on the finished fabrics as the glyoxal did. The advantage of chitosan in the combination of glyoxal and chitosan system was the improvement of the breaking strength retention of the finished fabrics without affecting the durable press property of the finished fabrics. However, the yellowing of the finished fabric was still a problem when the finished fabrics were treated with the combination of glyoxal and chitosan system. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1372–1377, 2006  相似文献   

13.
Cotton fabric with excellent antibacterial durability was obtained when treated with chitosan‐containing core‐shell particles without any chemical binders. These amphiphilic nanosized particles with antibacterial chitosan shells covalently grafted onto polymer cores were prepared via a surfactant‐free emulsion copolymerization in aqueous chitosan. Herein, two core‐shell particles, one with poly(n‐butyl acrylate) soft core and another with crosslinked poly(N‐isopropylamide) hard core, were synthesized and applied to cotton fabric by a conventional pad‐dry‐cure process. Antimicrobial activity was evaluated quantitatively using a Shake Flask Method in which the reduction of the number of Staphylococcus aureus cells was counted. The results showed that treated fabric had an excellent antibacterial property with bacterial reduction higher than 99%. The antibacterial activity maintained at over 90% reduction level even after 50 times of home laundering. The fabric surface morphology as well as the effect of latex particles with different core flexibilities on fabric hand, air permeability, break tensile strength, and elongation was investigated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1787–1793, 2006  相似文献   

14.
A series of novel hydrogels based on carboxymethyl chitosan (CMCS) has been synthesized by a cross-linking reaction between CMCS and various amounts of N,N′-bis [4-(isothiocyanate carbonyl)phenyl] pyromellitimide as a cross-linker to produce pyromellitimide benzoyl thiourea–CMCS hydrogels designated as PIBTU–CMCS (1–4). Hydrogel structures were identified by elemental analyses and FTIR and 1H-NMR spectroscopy. The prepared hydrogels were characterized for their properties to understand the influence exerted by controlled structural variations in these hydrogels. All the hydrogels showed a greater antibacterial activity on Gram-positive than Gram-negative bacteria. They also exhibited higher antifungal activities. Their antimicrobial activity improved by increasing their cross-linking degree.  相似文献   

15.
Acrylic acid was grafted to ozone‐treated poly(3‐hydroxybutyric acid) (PHB) and poly(3‐hydroxybutyric acid‐co‐3‐hydroxyvaleric acid) (PHBV) membranes. The resulting membranes were further grafted with chitosan (CS) or chitooligosaccharide (COS) via esterification. These CS‐ or COS‐grafted membranes showed antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, methicilin‐resistant Staphylococcus aureus (MRSA), and S. aureus. The antibacterial activity to E. coli was the highest, whereas the antibacterial activity to MRSA was the lowest among these four bacteria tested. Acrylic acid grafting can increase the biodegradability with Alcaligens faecalis, whereas CS and COS grafting can reduce the biodegradability. In addition, CS‐grafted PHBV membrane showed higher antibacterial activity and lower biodegradability than COS‐grafted PHBV membrane. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 12: 2797–2803, 2003  相似文献   

16.
采用交联改性降解壳聚糖对棉织物进行接枝改性,考察壳聚糖接枝改性对棉织物雷马素活性染料染色性能的影响.结果表明:棉织物经壳聚糖改性后,增加了织物表面对染料阴离子的亲和力和固着力,上染率和K/S值都有所提升,其固色率也有很大提高,均达80%以上;经雷马素红RR和雷马素黄RR染色后,改性棉织物的干、湿摩擦牢度和耐皂洗褪色同未改性棉织物一样,分别为4、3~4和4级,耐皂洗沾色降低半级,为3~4级.用雷马素蓝RR染色后,改性棉织物干摩擦牢度提高半级,达4级,湿摩擦牢度和耐皂洗等级同未改性棉织物一样,分别为3~4和4级.  相似文献   

17.
以羧甲基壳聚糖(CMC-Na)为接枝骨架、三苯基氯化锡(Ph_3SnCl)为接枝单体,用80%的甲醇水溶液作溶剂在20℃反应2 d,合成了三苯基锡壳聚糖羧酸酯(CMC-SnPh_3),借助红外光谱、热重分析、差热分析、X射线衍射等分析手段对CMC-SnPh_3的结构进行了表征,并进行杀钉螺活性实验。结果表明:分析的谱图数据与CMC-SnPh_3的结构相符,证明CMC-SnPh_3接枝共聚物的生成;CMC-SnPh_3的浓度大于10 mg/L时,能抑制钉螺七爬,CMC-SnPh_3的浓度大于1 mg/L,室温浸泡3 d后,钉螺的死亡率达100%,该接枝共聚物具有高效杀钉螺活性。  相似文献   

18.
以壳聚糖为原料,在碱性条件下合成了标题化合物,考察了其对稀土离子La3+、Nd3+、Sm3+的吸附性能.讨论了时间、溶液的酸度、初始离子浓度、羧甲基取代度对吸附性能的影响.发现羧甲基壳聚糖对稀土离子有较强的吸附性,吸附性满足Langmuir等温式.  相似文献   

19.
The layered material of sodium ferric silicate (SFS) has good adsorption properties for cationic dyes, but its stacking properties limit its application. The organic–inorganic composite assembled by macromolecular polymer and inorganic material can improve this situation. Carboxymethyl chitosan (CC) was loaded onto SFS, and the compound was characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscope (TEM), Brunauer–Emmett–Teller (BET), zero energy thermonuclear assembly (Zeta), and Fourier transform infrared spectroscopy (FT-IR). The results showed that CC was successfully supported in the layered structure of SFS, and the adsorption capacity of the composite for methylene blue (MB) was 729.67 mg g−1. The adsorption process was described by pseudo second-order kinetics, Langmuir isothermal equation, and intraparticle diffusion. The adsorption process was endothermic and spontaneous, and the monomolecular adsorption was dominant.  相似文献   

20.
Cotton fleece is not able to meet the federal flammability standard for general apparels (CFR 1610) without flame retardant treatment. Consequently, cotton fleece is not available in the market in spite of high demands. In our previous research, we studied the application of a hydroxyl‐functional organophosphorus oligomer as a flame retardant finishing agent for cotton fleece. In this research, we investigated the use of aluminum hydroxyphosphate (AHP) formed in situ on cotton by the reaction of aluminum sulfate and sodium phosphates to reduce the flammability of cotton fleece. We found that the AHP formed on cotton is effective in reducing the cotton fleece's flammability from “Class 3” to “Class 1.” Elemental analysis of aluminum and phosphorus in the AHP shows that the mole ratio of Al/P changes as the pH value of the sodium phosphates solution changes. The pH of the sodium phosphate solutions also affect the quantity of AHP formed on the cotton fleece. The treated cotton fleece retains “Class 1” flammability after one home laundering or the combination of dry‐cleaning and hand washing procedures. The treatment increases the whiteness of the cotton fleece whereas it reduces its bursting strength. The cotton fleece thus treated is also investigated using differential scanning calorimetry and scanning electron microscopy. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

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