氧氟沙星-壳聚糖-明胶共混膜的制备及表征

制备了壳聚糖 明胶共混膜 ,测定了壳聚糖 明胶共混膜的抗张强度 ,并以抗张强度最大的壳聚糖 明胶共混膜为载体 ,氧氟沙星为模型药物制得具有抗菌性能的氧氟沙星 -壳聚糖 -明胶共混膜。通过红外光谱 (FT -IR) ,X射线衍射 (X ray) ,扫描电子显微镜 (SEM)表征了共混膜的特性。结果表明 :明胶质量分数为 2 5 %时 ,壳聚糖 明胶共混膜的抗张强度最大 ,达 5 5MPa。壳聚糖、明胶、氧氟沙星三者在共混膜中有很好的相容性 ,并且形成了分子间氢键     

丝素/羧甲基壳聚糖共混膜的结构性能探讨

将含有甘油和戊二醛的丝素与羧甲基壳聚糖按一定比例混合,制得丝素/羧甲基壳聚糖共混膜,对共混膜的结构与性能进行了探讨。结果表明:随着羧甲基壳聚糖含量的增加,共混膜的透气率增大,加入交联剂戊二醛有效地改善了共混膜的力学性能,但其透气率有所降低;当丝素与羧甲基壳聚糖的质量比为4/1时,共混膜的断裂强度最大,力学性能较好,共混膜相容性较好,其断面光滑、致密。制备丝素/羧甲基壳聚糖共混膜的较佳条件为:丝素中的甘油质量分数为15%,戊二醛质量分数为0.075%,丝素与羧甲基壳聚糖质量比为4/1。     

明胶/壳聚糖共混膜的制备

本文研究了明胶与壳聚糖共混制膜技术,考察了影响交联反应的因素。结果表明,共混体系中明胶和壳聚糖的比例、体系的pH影响较大,而体系的温度的影响不显著;通过对制备得到的明胶-壳聚糖共混膜进行的X-RD证明,明胶和壳聚糖分子间发生了交联反应。     

壳聚糖季鏻盐共混膜的制备及性能研究

用溶液共混法成功地制备了壳聚糖与季鏻盐共混膜,并利用红外光谱、透光率、力学性能、吸水率及抑菌性能测试对其进行了表征。结果表明,共混膜中壳聚糖分子与季鏻盐分子间存在一定相互作用及良好的相容性,季鏻盐含量的增加减小了共混膜的吸水率,增加了其抑菌性能,在季鏻盐含量为20%时,共混膜的综合性能最佳,其中,抗张强度达到60.8 MPa,透光率为85%。     

光交联明胶-壳聚糖共混膜制备及性能研究

本实验用以聚乙烯醇-苯乙烯基吡啶盐的缩合物(PVA-SbQ)为光敏剂,运用紫外光辐照法以制备交联明胶-壳聚糖共混膜。用傅立叶红外、X-射线衍射方法对膜的结构进行表征,并对膜的力学性能、吸湿率、透光率性能进行研究。研究表明:PVA-SbQ分子与明胶、壳聚糖分子间存在氢键作用,光交联后,共混膜形成网状结构,有效地改善了共混膜的力学性能、吸湿性和紫外屏蔽性能等。     

壳聚糖及其改性膜的研究进展及在水处理领域的应用

壳聚糖及其衍生物具有功能基团丰富、化学活性强、亲水性高、易从可再生资源中获得等优势,是去除水体中杂质的理想材料。由于分子内和分子间的氢键作用、范德华力以及分子的规整性使壳聚糖易成膜,将壳聚糖与膜分离技术结合制备抗污染性能强、选择特异性高、活性吸附位点丰富、稳定性强且具有良好再生能力的壳聚糖膜,并应用在废水处理领域成为国内外学者研究的热点。本文围绕壳聚糖及其改性膜的研究进展及在废水处理上的应用进行综述,分别从壳聚糖作为成膜基质和膜表面修饰材料两个方面进行详细介绍。总结了共混改性、交联改性、印迹改性以及新型的磁性纳米粒子负载改性、表面等离子体改性、MOFs改性等改性方法对壳聚糖膜性能的影响及在水处理中的应用效果,最后对壳聚糖膜在分离领域的发展方向进行了展望。     

交联壳聚糖/蒙脱土复合膜的制备及性能研究

以壳聚糖（CS）为基质材料，蒙脱土（MMT）为填料，采用戊二醛（GA）交联改性并结合溶液插层法制备了交联壳聚糖/蒙脱土（CS/GA/MMT）复合膜。通过扫描电子显微镜、X射线衍射仪、红外光谱仪及热重分析仪对复合膜的结构进行了表征，考察了MMT用量对复合膜的吸水性能、水蒸气阻隔性能和力学性能的影响。结果表明，交联改性CS可提高CS膜的耐水性，CS/GA膜的吸水率较CS膜降低了9.6 %；MMT可提高复合膜的耐水性、水蒸气阻隔性能、力学性能和热稳定性；当MMT的用量为CS质量的5 %时，复合膜的各项性能较好，吸水率、水蒸气透过率和断裂伸长率较CS膜分别降低了37.3 %、36.7 %和41.9 %，且拉伸强度提高了160.5 %。     

油酸对壳聚糖/玉米醇溶蛋白复合膜液流变及膜性能的影响

为了提高壳聚糖/玉米醇溶蛋白膜的机械性能，将壳聚糖液与玉米醇溶蛋白液共混，向其中加入0%、15%、30%、45%（w/w）的油酸改性，研究膜液的粒径、zeta电位、静态和动态流变特性；然后，分析油酸添加量对膜阻隔性能，机械性能和相容性的影响。结果表明：添加油酸后，膜液体系粒径增大、分散均匀，添加30%油酸的膜液分散性更好，PDI为0.34，粒径为1307.5nm。随着油酸含量增大，膜液粘度减小，流动指数增大，弹性模量和粘性模量增加。OA-30膜机械性能较好，抗拉强度达到36.37MPa，断裂延伸率达到22.32%。膜的阻隔性增强，水蒸气、氧气透过率分别降低了44.21%和66.52%。复合膜中壳聚糖与玉米醇溶蛋白分子相容性好，表面光滑平整。综上所述，油酸改性改善了壳聚糖/玉米醇溶蛋白复合膜性能。     

壳聚糖对玉米淀粉可食膜性能的影响

以玉米淀粉为原料，结合壳聚糖在增塑剂甘油的作用下通过溶液浇铸法制备了玉米淀粉/壳聚糖复合可食薄膜，采用红外光谱和扫描电子显微镜对薄膜结构和微观形貌进行了表征，研究了壳聚糖的含量对薄膜力学性能、水蒸气透过性、阻油性及抗菌性能的影响。结果表明，适量的壳聚糖可以较明显地改善薄膜的力学性能，提高其隔水和阻油性能；壳聚糖与淀粉质量比为1/3时制得的薄膜结构均匀，拉伸强度为21.54 MPa，是淀粉膜的2.52倍，水蒸气透过率为4.52×10^-5 g/（mm·d），较淀粉膜降低了49.3 %，薄膜能抑制大肠杆菌和金黄色葡萄球菌的生长，对二者的抑菌率分别为43.55 %和32.89 %。     

单宁酸对海藻酸钠/壳聚糖微球性能的影响

研究了单宁酸的引入对海藻酸钠/壳聚糖水凝胶在微球化和微胶囊化应用性能方面的影响.首先制备了单宁酸交联改性的海藻酸钠/壳聚糖水凝胶微球.利用傅里叶变换红外光谱分析了共混物分子结构间的相互作用,采用热重分析仪考察了微球热稳定性,并研究了单宁酸的加入对微球粒径、含水量和溶胀性的影响.结果表明由于单宁酸与海藻酸钠/壳聚糖之间的...     

Quaternized chitosan/functionalized carbon nanotubes composite anion exchange membranes

Natural alkaline polyelectrolyte chitosan has been considered to be a promising anion exchange membrane (AEM) material due to its low cost and easy quaternization. To further improve the ionic conductivity and mechanical property of quaternized chitosan (QCS), QCS functionalized carbon nanotubes (QCS@CNTs) were prepared and used as a novel nanofiller to modify the membrane matrix. The QCS coating layer on the surface of CNTs can not only improve the dispersion of CNTs and thus promote the load transfer from the QCS matrix to stiff CNTs, but also endow CNTs with a certain hydroxide ions exchange ability. The results show that the addition of QCS@CNTs slightly decreased the ionic conductivity of the composite membranes while the tensile strength and alkaline stability of these membranes were significantly improved, indicating the potential application of these composite membranes in AEM fuel cells. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47778.     

Preparation and antibacterial properties of polycaprolactone/quaternized chitosan blends

This article is a preliminary study on antibacterial blends of polycaprolactone, chitosan and quaternized chitosan by melt processing. Blends were characterized, mechanical test and antibacterial evaluation against Escherichia coli and Staphylococcus aureus, were conducted. Results showed that the antibacterial potential of chitosan was limited in blends and polycaprolactone/chitosan did not show significant antibacterial effect compared with neat polycaprolactone (PCL). Inhibition rates of polycaprolactone/quaternized chitosan were 39.2％–99.9％ against Escherichia coli, while inhibition rate was 40.9％–99.9％against Staphylococcus aureus. When quaternized chitosan (QCTS) content was up to 20％, blends exhib-ited 99.9％inhibition rates against both two types of bacteria.     

Studies of adsorption of alkaline trypsin by poly(methacrylic acid) brushes on chitosan membranes

Poly(methacrylic acid)‐grafted chitosan membranes (chitosan‐g‐poly(MAA)) were prepared in two sequential steps: in the first step, chitosan membranes were prepared by phase‐inversion technique and then epichlorohydrin was used as crosslinking agent to increase its chemical stability in acidic media; in the second step, the graftcopolymerization of methacrylic acid onto the chitosan membranes was initiated by ammonium persulfate (APS) under nitrogen atmosphere. The chitosan‐g‐poly(MAA) membranes were first used as an ion‐exchange support for adsorption of trypsin from aqueous solution. The influence of pH, equilibrium time, ionic strength, and initial trypsin concentration on the adsorption capacity of the chitosan‐g‐poly(MAA) membranes have been investigated in a batch system. Maximum trypsin adsorption onto chitosan‐g‐poly(MAA) membrane was found to be 92.86 mg mL^?1 at pH 7.0. The experimental equilibrium data obtained for trypsin adsorption onto chitosan‐g‐poly(MAA) membranes fitted well to the Langmuir isotherm model. The adsorption data was analyzed using the first‐ and second‐order kinetic models, and the experimental data was well described by the second‐order equation. More than 97% of the adsorbed trypsin was desorbed using glutamic acid solution (0.5M, pH 4.0). In addition, the chitosan‐g‐ poly(MAA) membrane prepared in this work showed promising potential for various biotechnological applications. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Synthesis of ion‐imprinting chitosan/PVA crosslinked membrane for selective removal of Ag(I)

A novel ion‐imprinted membranes were synthesized for selective removal and preconentration for Ag(I) ions from aqueous solutions. The membranes were obtained via crosslinking of chitosan (CS), PVA, and blend chitosan/PVA using glutaraldehyde (GA) as crosslinker. The FTIR spectra were used to confirm the membrane formation. Comparing with the nonimprinted membranes, Ag(I)‐imprinted CS and CS/PVA has higher removal capacity and selectivity for Ag⁺ ions. An enhancement in the Ag⁺ removal capacity by ～ 20% (from 77.8 to 94.4 mg g^–1) and ～ 50% (from 83.9 to 125 mg g^–1) was found in the Ag(I)‐imprinted CS and Ag(I)‐imprinted CS/PVA membranes, respectively, when compared with the nonimprinted membranes. Removal equilibra was achieved in about 40 min for the non‐ and ion‐imprinted CS/PVA. The pH and temperature significantly affected the removal capacity of ion‐imprinted membrane. The relative selectivity coefficient values of Ag⁺/Cu²⁺ and Ag⁺/Ni²⁺ are 9 and 10.7 for ion‐imprinted CS membrane and 11.1 and 15 for ion‐imprinted CS/PVA membrane when compared with nonimprinted membranes. The imprinted membranes can be easily regenerated by 0.01M EDTA and therefore can be reused at least five times with only 15% loss of removal capacity. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Highly selective custom-made chitosan based membranes with reduced fuel permeability for direct methanol fuel cells

Custom-made nanocomposite proton exchange membranes (PEMs) are fabricated using the blends of sulfonated chitosan (S-Chitosan) and sulfonated graphene oxide (SGO) nanosheets for direct methanol fuel cells (DMFCs). Sulfonation of chitosan and GO are carried out by 1,3-propane sultone and sulfanilic acid, respectively. Scanning electron microscope (SEM) with energy dispersive X-ray investigation revealed that the thick, folded and wrinkled sheet-like morphology of SGO and the existence of elemental sulfur. SEM and atomic force microscopy images showed the uniform dispersion of hydrophilic SGO nanosheets. Besides the S-Chitosan/SGO membranes showed higher water uptake, swelling ratio and ion exchange capacity due to the enhancement in hydrophilicity. The modified PEMs displayed improvement in proton conductivity since the ion-exchangeable sulfonic acid groups facilitate the proton conduction and effectively resist the methanol permeability by forming a strong hydrogen bond network with chitosan and thus diminish the void volume. Particularly, S-Chiotsan-1 membrane showed superior proton conductivity of 4.86 × 10⁻³ Scm⁻¹ at (25°C), selectivity of 1.89 × 10⁵ Scm⁻³ s and lesser methanol permeability of 2.57 × 10⁻⁸ cm²s⁻¹. Overall results suggest that the S-Chitosan/SGO membranes found to be a suitable alternate for Nafion® in DMFCs.     

Diffusional properties of chitosan hydrogel membranes

Chitosan membranes were prepared by a solvent evaporation technique, followed by crosslinking with glutaraldehyde and coating with BSA. The effects of crosslinking and BSA coating on the pore structure of such prepared hydrogel chitosan membranes were determined. The diffusion rates of 12 non‐electrolytes ranging in molecular radius between 2.5 and 14 Å through the membranes were measured, and the results were interpreted in terms of the capillary pore model and free volume model of solute diffusional transport through hydrogel membranes. Glutaraldehyde crosslinking was found to reduce the membrane water content and consequently the membrane pore size and surface porosity, whereas further BSA coating brought about the opposite effect. The latter effect lessened with an increase in glutaraldehyde pretreatment of the membranes. The optimal chitosan membrane preparation, compromising between the solute flux and membrane stability and durability was obtained when the membranes were crosslinked with glutaraldehyde at concentrations between 0.01 and 0.1% (w/w). The knowledge of transport properties and of physical strength of the membranes is of importance for the development of chitosan‐based controlled release systems. © 2001 Society of Chemical Industry     

聚醚砜／壳聚糖共混耐污染超滤膜的研制

采用相转化法,以聚醚砜（PES）、壳聚糖、聚乙二醇400（PEG400）、吐温80和LiCl／N,N-二甲基乙酰胺（DMAo）混合溶剂为原料制备聚醚砜／壳聚糖共混耐污染超滤膜。并对影响超滤膜结构和性能的各个因素进行了研究。结果表明．在壳聚糖质量分数为0．3％、反应温度为80℃条件下制备的聚醚砜／壳聚糖共混耐污染超滤膜性能最优。在25℃、0．1MPa操作条件下,膜的纯水通量为745．22（L／m2·h）,牛血清白蛋白截留率为91．79％。改性后的超滤膜表面接触角为74．6°,阻力增大系数为0．54,通量衰减速度小于未改性超滤膜,亲水性能和耐污染性能得到很大提高。     

壳聚糖季铵盐的制备及应用进展

壳聚糖季铵盐是一种具有广阔应用前景的阳离子聚合物。概述了壳聚糖季铵盐的制备方法以及壳聚糖季铵盐在水处理、化妆品、制膜等领域的应用进展情况,并展望了壳聚糖季铵盐的研究趋势。     

季铵化壳聚糖-聚苯乙烯共混膜的制备及表征

以十六烷基三甲基溴化铵(CTAB)为表面活性剂,过硫酸钾为引发剂制备了聚苯乙烯微乳液,用共混法制备了3种不同质量比的季铵化壳聚糖和聚苯乙烯微乳液的共混膜.研究了该膜的温度和pH的敏感性及力学强度.结果表明,共混膜的拉伸强度与纯壳聚糖膜相比有较大提高,而且该膜仍然具有一定的温度敏感性和pH敏感性,有较好的应用价值.     

壳聚糖季铵盐及其复合物的研究进展

壳聚糖季铵盐及其复合物是一种很有应用前景的材料,作者综述了壳聚糖季铵盐及其复合物在载基因、载药、抗菌创伤材料、抗凝血材料、水处理材料等领域的研究进展。