交联改性壳聚糖在棉织物活性染料染色中的应用

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.     

Preparation and characterization of venlafaxine hydrochloride‐loaded chitosan nanoparticles and in vitro release of drug

The venlafaxine hydrochloride (VHL)‐loaded chitosan nanoparticles were prepared by ionic gelation of chitosan (CS) using tripolyphosphate (TPP). The nanoparticles were characterized using FTIR, differential scanning calorimetry, X‐ray diffraction, dynamic light scattering, transmission electron microscopy, and X‐ray photoelectron spectroscopy. The effect of concentration of CS, polyethylene glycol (PEG), VHL and CS/TPP mass ratio on the particle size and zeta potential of nanoparticles was examined. The particle size of CS/TPP nanoparticles and VHL‐loaded CS/TPP nanoparticles was within the range of 200–400 nm with positive surface charge. In the case of VHL‐loaded nanoparticles and PEG‐coated CS/TPP nanoparticles, the particle size increases and surface charge decreases with increasing concentration of VHL and PEG. Both placebo and VHL‐loaded CS/TPP nanoparticles were observed to be spherical in nature. PEG coating on the surface of CS/TPP nanoparticles was confirmed by XPS analysis. Maximum drug entrapment efficiency (70%) was observed at 0.6 mg/mL drug concentration. In vitro drug release study at 37°C ± 0.5°C and pH 7.4 exhibited initial burst release followed by a steady release. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

甲壳素和甲壳胺纤维质量的影响因素

概述了影响甲壳素和甲壳胺纤维质量的因素,如甲壳素和甲壳胺的品质、纺丝原液的溶剂选择及浓度的确定、凝固浴的确定;简述了通过化学改性来改善甲壳素和甲壳胺纤维性能;介绍了国内外为改善纤维质量所作的最新研究。     

Improved mechanical properties of chitosan fibers

A highly deacetylated chitosan from shrimp with a degree of deacetylation of 95 ± 3% was prepared and spun into a monofilament fiber using a solution of 5% by weight chitosan in 5% by volume aqueous acetic acid. Samples of the spun fibers were immersed in separate solutions containing phosphate ions and phthalate ions, and subsequently washed and dried. The various solutions ranged in pH from 4.12 to 7.75. The highest dry mechanical properties resulted from solutions containing phthalate ions between 4.5–5.5 pH, and from solutions containing phosphate ions at pH 5.4. Immersion time was varied between 1 and 60 min at 25.8°C, and temperature was varied between 25.8 and 70.0°C, in the phosphate ion solutions at a pH of 5.8. Dry mechanical properties were highest at 25.8°C and after 1 h of treatment. Chitosan films were subjected to similar treatments in phosphate and phthalate ion solutions. Fourier transform infrared data (FTIR) on the films suggest that some interaction is occurring between the phosphate ions and the amine group on the chitosan backbone. An additional experiment was performed whereby the same chitosan was used to prepare a dope of 4% by weight chitosan in 4% by volume aqueous acetic acid with 30% by volume methanol. This solution was spun into fibers, but was subjected to a “final draw” by increasing the speed of the winder. With increasing the final draw, denier and elongation‐at‐break decreased, while the other mechanical properties showed a marked increase. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 1721–1732, 1999     

Morphology of ultrafine polysulfone fibers prepared by electrospinning

Ultrafine fibers of bisphenol‐A polysulfone (PSF) were prepared by electrospinning of PSF solutions in mixtures of N,N‐dimethylacetamide (DMAC) and acetone at high voltages. The morphology of the electrospun PSF fibers was investigated by scanning electron microscopy. Results showed that the concentration of polymer solutions and the acetone amount in the mixed solvents influenced the morphology and the diameter of the electrospun fibers. The processing parameters, including the applied voltage, the flow rate, and the distance between capillary and collection screen, were also important for control of the morphology of electrospun PSF fibers. It was suggested that uniform ultrafine PSF fibers with diameter of 300–400 nm could be obtained by electrospinning of a 20 % (wt/v) PSF/DMAC/acetone (DMAC:acetone = 9:1) solution at 10–20 kV voltages when the flow rate was 0.66 ml h^?1 and capillary–screen distance was 10 cm. Copyright © 2004 Society of Chemical Industry     

Characteristics of polyimide ultrafine fibers prepared through electrospinning

A novel route for making polyimide sub‐micron fibers is described. The ultrafine fibers are prepared by electrospinning a poly(amic acid) solution, a precursor of polyimide, followed by thermal imidization. The fiber diameters, which are much smaller than conventionally spun fibers, range from a few tens of nanometers to several micrometers. A rectangular cross‐section is observed in the case of sub‐micron fibers with a cross‐sectional dimension below ～500 nm. © 2003 Society of Chemical Industry     

Improvements in the drying process for wet-spun chitosan fibers

Chitosan fibers were wet spun from a 6% by weight chitosan in 3% by volume acetic acid solution. The fibers were collected as a 20 filament yarn intended for use as a chaff substrate. The yarn had to be sufficiently dry following spinning to allow for winding and subsequent separation of the filaments. Drying of the yarn was attempted using various techniques including direct and radiant heat, forced air, and chemical drying agents. Product yarns were analyzed for ease of separation of the filaments, as well as comparison of mechanical properties. Individual fibers were evaluated on the basis of moisture content, surface morphology and fiber diameter. Results indicate that the particular drying method or agent used has a considerable impact upon all of the characteristics listed above. A methanol dry bath was found to provide optimum drying of the chitosan yarn, producing filaments with low moisture content that separated easily from one another. Methanol drying yielded chitosan fibers with smaller diameter, superior surface smoothness and superior mechanical properties to fibers dried using forced air, heat, or other tested drying agents such as acetone and isopropanol. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 1435–1444, 1998     

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     

Effect of carboxymethylation on the absorption and chelating properties of chitosan fibers

Chitosan fibers were treated with chloroacetic acid to prepare partially substituted carboxymethyl chitosan fibers. Fibers with different levels of carboxymethylation were prepared by controlling the ratio between the fiber and the amount of chloroacetic acid. The absorption properties of the modified fibers for Cu(II) ions were studied at different concentrations, temperature, time, and pH. Results showed that the carboxymethylated chitosan fibers were more effective than the original chitosan fibers in removing Cu(II) ions from aqueous solutions. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3110–3115, 2006     

离子凝胶法制备壳聚糖纳米微粒

采用离子凝胶法,以不同浓度壳聚糖溶液与多聚磷酸盐(TPP)溶液配比反应制备壳聚糖纳米微粒,观察了壳聚糖、多聚磷酸盐浓度、壳聚糖与多聚磷酸盐的质量比和反应体系pH值对纳米微粒制备的影响。在壳聚糖与多聚磷酸盐溶液浓度分别为0.6~3.0 mg/mL与0.5~1.5 mg/mL时,保持质量比在3∶1~6∶1之间,可稳定得到壳聚糖纳米微粒;当pH值为5.0~6.0时壳聚糖纳米微粒保持稳定,当pH>7.0则出现沉淀。     

The absorption and release of silver and zinc ions by chitosan fibers

When chitosan fibers were treated with AgNO₃ and ZnCl₂ solutions, the silver and zinc ions were chelated by chitosan through the amine groups in the fibers. These novel metal ions can be released into the solution when the silver‐ and zinc‐containing fibers are placed in contact with normal saline. Results showed that the silver‐containing chitosan fibers have good antimicrobial properties, while the zinc‐containing fibers can be used to deliver zinc ions in wound care applications. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 766–771, 2006     

丙烯酸接枝改性壳聚糖纤维的制备及性能

在引发剂过硫酸铵(APS)的作用下,采用丙烯酸(AA)接枝改性壳聚糖(CS),制备出CS-AA接枝共聚物,经湿法纺丝将其纺制成纤维,再用戊二醛对纤维进行一定程度的交联,可得到较好力学性能的改性CS纤维。结果表明:CS质量分数(相对AA)为14.3%,APS(相对AA)的摩尔分数为1.0%,反应温度65℃,反应时间6 h,凝固浴中无水乙醇和质量分数为10%氢氧化钠水溶液的体积比为50/50。在此条件下制得的纤维的断裂强度为0.55 cN/dtex,断裂伸长率为367%,经交联处理后纤维的断裂强度达2.03 cN/dtex。     

Spinning of hydroalcoholic chitosan solutions: Mechanical behavior and multiscale microstructure of resulting fibers

The morphology and mechanical properties of chitosan fibers obtained by spinning of hydroalcoholic (1,2propanediol/water) chitosan solutions of low DA and high molecular mass are reported. The impact of processing parameters on final fiber properties, such as fiber stretching at different steps of the spinning process, is investigated. A stretching ratio applied during the fiber coagulation appeared to have no significant effect on mechanical properties, whereas fiber drawing after the coagulation step, that is, during the washing step was a key parameter for the control of macromolecular orientation, fiber tenacity, and Young's modulus. The microstructure and morphology of the various as-spun chitosan fibers were studied by means of wide-angle and small-angle X-ray scattering and scanning electron microscopy. Microstructure impacts mechanical properties from the interplay of different deformation mechanisms acting at different length scales of the microstructure, namely the macromolecular orientation, the semicrystalline morphology, and the core–shell structure. The obtained monofilament fibers (45–70D) can be knitted. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47130.     

壳聚糖干湿纺中的空气层工艺研究

采用干湿法纺丝制备了壳聚糖纤维以期改善纤维强度。对纺丝流程中空气层的工艺作用进行了详细讨论，研究结果表明：空气层的存在和喷头拉伸比对提高纤维强度起着重要的作用。在喷头拉伸比大于1的情况下，原液细流在空气层中得到轴向拉伸，加大了初生纤维的取向度，所以纤维强度得到加强。纤维截面的SEM电镜照片也证实干湿纺纤维的结构比湿纺纤维密实。     

Electrospun ultrafine composite fibers from organic‐soluble chitosan and poly(ethylene oxide)

The ultrafine composite fibers had been successfully achieved by electrospinning of chloroform solutions of octadecyl chitosan (O‐CS) and poly(ethylene oxide) (PEO). The ultrafine composite fibers membranes were subjected to detailed analysis by Fourier‐transformed infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and water contact angle (WCA). The FTIR results confirmed that ultrafine composite fibers contained the two polymers. The SEM images showed that the morphology and diameter of the composite fibers were mainly affected by the weight ratio of O‐CS/PEO, the electric field strength, and the collection distance. The WCA data demonstrated that the composite fibers membranes performed a quite hydrophobic character. The special morphology of neck and porous structure was observed experimentally during electrospinning. The neck structure was due to the fibers elongated in the direction of stretching through the electric field, and the porous structure was decided by the competition between the phase separation and the fast evaporation rate of chloroform. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

纯壳聚糖纤维关键技术研究及其产业化

简介了纯海洋动物再生纤维—壳聚糖纤维的理化性质、生物学特性、抑菌机理以及调节人体皮肤微生态平衡的保健功能。重点阐述了由废弃虾、蟹壳为原料,生产纯壳聚糖纤维的关键技术和全程无毒化纺丝的工艺优点,纯壳聚糖纤维在医药、工业、纺织等领域的应用现状,以及实现原料国产化及纤维产业化发展。     

Viscoelastic sol–gel state of the chitosan and alginate solution mixture

The rheological behavior of chitosan/alginate solutions was investigated in relation to gelation and polyelectrolyte complex (PEC) formation. Before mixing, the chitosan and the alginate solutions were both homogeneous fluids. However, heterogeneity developed after mixing, accompanied by a serious increase of viscosity. To determine the sol–gel state of the solutions, the viscoelastic variables, such as the dynamic storage modulus (G′) and loss modulus (G″), the loss tangent, and the viscoelastic exponents for G′ and G″, were obtained. Depending on the concentration, the chitosan/alginate solutions revealed unexpected rheological behavior. At a polymer concentration of 1.0 wt %, the chitosan/alginate solution was in a viscoelastic gel state, whereas, at higher concentrations, viscoelastic sol properties were dominant. A viscoelastic gel state for the chitosan/alginate solution was induced based on the weak formation of fiber‐shaped precipitates of a PEC at a low polymer concentration. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1408–1414, 2007     

准均相反应制备磺化壳聚糖

以工业壳聚糖为原料,先制成一定浓度的壳聚糖准均相溶液,再以浓硫酸-氯磺酸磺化试剂进行磺化,获得了水溶性较好、含硫量较高的磺化壳聚糖,硫含量为0.13%~0.15%,同时确立最佳反应条件为:壳聚糖85.7 g/L,4%醋酸溶液20 mL,反应时间1 h,H2SO4∶HSO3C l=1∶2,硫酸化/磺化试剂总浓度为42.86%,反应温度为50℃。IR光谱分析表明,该衍生物具有与肝素相似的结构,是一种非常具有潜力的新型类肝素。     

Gel spinning of polyacrylonitrile fibers with medium molecular weight

A new gel‐spinning method was employed to prepare polyacrylonitrile (PAN) fibers from a PAN spinning solution with dimethylsulfoxide and water as a mixed solvent. Aging at 25 °C for 120 min brought the spinning solution to the sol–gel transition and a three‐dimensional gel formed before entering the coagulation bath. The as‐spun fibers from the solution at the sol–gel transition and in the gel state possess a circular cross‐section. Compared with dry‐jet wet‐spun fibers, the gel‐spun fibers have a more compact structure, fewer voids and better mechanical properties after a three‐stage drawing. Moreover, the gel‐spun fibers obtained from the extraction bath have a more homogeneous microstructure and better packed supermolecular structure. The physical properties of the extracted gel‐spun fibers are also better than those of coagulated gel‐spun fibers. Copyright © 2010 Society of Chemical Industry