Effect of chitosan addition to BTCA/CA processed cotton fabrics for adsorbing metallic ions from waste water

One of the most important properties of chitosan, a derivative of chitin, is that it is able to chelate with certain heavy metal ions, and this property can be applied to process waste water containing heavy metal ions. In this research, using BTCA/CA as a crosslinking reagent with chitosan added, cotton fabrics were cured and allowed to undergo an adsorption reaction in CuSO₄ and ZnSO₄ solutions. The effect of different curing temperatures and time, as well as different adsorptive temperatures and time, were studied. The cotton processed fabrics were analyzed by Fourier transform infrared analysis (FTIR), scanning electronic microscope (SEM), and thermal gravity analysis (TGA) to study the crosslinking reaction with the cotton‐processed fabrics. The results indicate: (1) the BTCA/CA‐processed cotton fabrics with an addition of chitosan have a better adsorptive capacity than the processed fabrics without chitosan; (2) the crosslinked fabrics are better in adsorbing copper ions as chitosan concentration, curing temperature and time, and adsorptive temperature and time increase; (3) the adsorption rate of copper and zinc ions are linearly proportional to the changes of time, so that the slope shows that the adsorption rate of crosslinked fabrics for copper ions is faster than for zinc ions. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3264–3269, 2006     

The study of rapid curing crease‐resistant processing on cotton fabrics. Part I. The effect of chitosan on the physical properties of processed fabrics

The principal aim of this study is to explore the effect of chitosan on the physical properties of cotton fabrics in rapid curing crease‐resistant processing. It was determined that compared with the traditional three‐stage processing, the addition of chitosan is beneficial to the absorbency of processed fabrics, dry‐wet wrinkle recovery angle, and tensile strength retention. In addition, the dry‐wet wrinkle recovery angle of processed fabrics increases with the increase of curing temperature and curing treatment time, but absorbency and tensile strength retention both decrease. Also, the dry‐wet wrinkle recovery angle and tensile strength retention of processed fabrics increase with higher chitosan concentrations, but the fabric's absorbency is reduced. In general, use of 0.5%≈︁0.75% chitosan with DMEU curing treatment conditions of 8%, 200°C for 30 s will provide optimum physical property balance for processed fabrics. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 35–40, 2000     

Preparation and multifunctional application of meso‐chitosan for the woolen process

This study used chitosan deacetylated to different degrees to process woolen fabrics via the nanometrization of sodium hydroxide of different concentrations. The analysis and determination of the bacterial resistance, shrink resistance, Fourier transform infrared, and dyeability were then carried out for the processed substances. The particle diameter was measured with light scattering and scanning electron microscopy. It was then reduced with 5% and higher concentrations of NaOH, in which the particle diameter was 150–750 nm. As for bacterial resistance, the processed cloth that was not oxidized by H₂O₂ had better bactericidal and bacteriostatic effects than the cloth that underwent the oxidation process. Chitosan and meso‐chitosan had a bacterial‐resistance effect on the woolen fabrics. The processed cloth also had a better shrink‐resistance rate, but the effect of nanometrization was not obvious. For the dyeability of the woolen fabrics, meso‐chitosan was better than chitosan. The higher degree of deacetylation of chitosan slightly improved the dyeability. The dyeability increased a little as the temperature of the curing treatment rose and the time of the curing treatment was extended. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 4080–4086, 2007     

Using Persulfate Oxidized Chitosan as a Novel Additives in Easy-Care Finishing for Cotton Textiles

Easy care finishing of cotton fabric using glyoxal in the presence and absence of low molecular weight chitosan, i.e., persulfate-oxidized chitosan, as a novel additive along with MgCl₂·6H₂O as an acid catalyst was studied in detail. Major factors affecting finishing reaction were studied with respect to glyoxal, oxidized chitosan, and catalyst concentrations in addition to curing time and temperature of treatment according to the pad-dry-cure method. The obtained results show the following findings: (a) increasing the glyoxal concentration from 5–50 g/l in absence of oxidized chitosan is accompanied by an increase in crease recovery angle and a decrease in tensile strength of the finished fabric, whereas that treated in the presence of oxidized chitosan shows a higher tensile strength and to some extent comparable crease recovery angle with respect to that finished in the absence of it when the concentration of glyoxal increases; (b) increasing the oxidized chitosan concentration is accompanied by decreasing crease recovery angle, whereas the tensile strength increases when glyoxal concentration increases within the range studied; (c) increasing the MgCl₂·6H₂O from 0–15 g/l is accompanied by an increase in the crease recovery angle and a decrease in tensile strength of the finished fabrics in the presence and absence of oxidized chitosan; (d) increasing the time and temperature of curing of the finished fabrics is accompanied by an increase in crease recovery angles and decreases in tensile strength; and (e) the dry wrinkle recovery angle of cotton fabric samples finished in presence of O-chitosan is decreased after washing, and the higher the washing cycle the lower the dry wrinkle recovery angle.     

Adsorption capacity,kinetics, and thermodynamics of chitosan nanoparticles onto cotton fabrics without any chemical binders

The stable adsorption of chitosan nanoparticles (CNs) onto cotton fabrics was successfully developed without any chemical binders. The adsorption kinetics, thermodynamics, and capacities under different experimental conditions were investigated. The structure and laundering durability of CNs‐adsorbed cotton fabrics (CNs‐cotton) were also characterized by Scanning Electron Microscope (SEM), Fourier Transform Infrared Spectroscopy (FTIR), X‐ray Photoelectron Spectroscopy (XPS), and Thermo Gravimetric Analysis (TGA). The adsorption capacities of cotton for CNs declined with the increasing CNs particle size and temperature. By contrast, adsorption capacities increased with the increasing adsorption pH and CNs mass concentration. The kinetic adsorption of CNs onto cotton fabrics was found to follow the pseudo‐second‐order kinetic model. The adsorption mechanism reflected a complex process, and the intra‐particle diffusion was not the only rate‐limiting step. The transfer and diffusion rates progressively increased with the decrease of adsorption temperature and CNs particle size. The negative values of the standard Gibbs free energy changes (ΔG°) and the standard enthalpy (ΔH°) indicated that the adsorption was exothermic and spontaneous at 5–75°C. The superior laundering resistance of CNs‐cotton was demonstrated after 30 consecutive washes, thereby proving the stable adsorption of CNs onto cotton fabrics without chemical binders. POLYM. COMPOS., 36:2093–2102, 2015. © 2014 Society of Plastics Engineer     

聚乙二醇接枝壳聚糖对涤纶织物性能的影响

以壳聚糖为原料,通过邻苯二甲酸酐封闭2位氨基,利用三聚氰氯将壳聚糖的6位羟基引入聚乙二醇(PEG2000)链上,得到水溶性较好的壳聚糖衍生物(TCSO-PEG2000)。用TCSO-PEG2000整理剂对涤纶织物进行处理,采用红外光谱和扫描电镜对整理剂及涤纶织物进行表征分析,研究整理剂的用量、焙烘时间、焙烘温度等对涤纶织物的强力、透气性、亲水性、抗静电等性能的影响。结果表明:在整理剂质量浓度为8 g/L、焙烘时间为5 min、焙烘温度为120℃时,涤纶织物具有较好的力学性能、亲水性能及抗静电性能。     

Wrinkle resistant properties and antibacterial efficacy of cotton fabrics treated with glyoxal system and with combination of glyoxal and chitosan system

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     

Cr (VI) adsorption from aqueous solutions on grafted chitosan

Chitosan was grafted on the surface of a cotton gauze (20, 50, and 100 mg chitosan g⁻¹ cotton) to improve its stability in aqueous solutions. The adsorption of hexavalent chromium ions from water on the grafted chitosan was evaluated to determine, by means of linear and nonlinear models, the kinetic and isotherm adsorption of the process. The kinetics of pseudo second-order, pseudo first-order, and adsorption isotherms type II were obtained, that is, a monolayer adsorption on nonporous adsorbents with physical adsorption was present. The most probable energy of adsorption corresponded to a physisorption with hydrogen bond interactions between chromium ions and ammonium groups. Moreover, three different cross-sectional areas of hexavalent chromium ions were calculated and used to estimate the specific surface area employed by active sites to adsorb metal ions in terms of chitosan or cotton mass. Finally, the percentage of the area occupied by chromium ions on the surface was estimated by dividing the resulting specific surface area in terms of cotton mass by the specific surface area of cotton reported in literature. As a result, it was determined that the occupied area is between 6% (for 20 mg chitosan g⁻¹ cotton)-24% (for 100 mg chitosan g⁻¹ cotton) from the total area of cotton.     

Absorption and release of zinc and copper ions by chitosan fibers

Chitosan fibers were treated with aqueous solutions of ZnCl₂ and CuSO₄·5H₂O to prepare zinc and copper containing fibers, respectively. Significant weight gains were obtained as the zinc and copper ions were absorbed onto the fibers through chelation with the primary amine groups. The fibers were then placed in contact with aqueous solutions containing NaCl and water soluble proteins, respectively, to assess the release of zinc and copper ions. Results showed that the release of zinc and copper ions were affected by the treatment temperature, time, and the composition of the contacting media. More metal ions were released when the fibers were in contact with aqueous protein solutions than in NaCl solution, indicating the binding abilities of the protein molecules for zinc and copper ions. The zinc and copper containing fibers were tested for their antimicrobial effects against several species of bacteria commonly found in wound and skin. Results showed that these metal containing chitosan fibers had much stronger antimicrobial properties than the original chitosan fiber. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Preparation and application of fluorocarbon polymer/SiO2 hybrid materials,part 2: Water and oil repellent processing for cotton fabrics by sol–gel method

This research employed different procedures for out water and oil repellent finish on cotton fabrics with fluorocarbon copolymer or its hybrid materials. The experimental results indicated that fabrics processed with fluorocarbon copolymer have larger contact angle for water and oil repellent finish, and the fabric processed with simultaneous bathing of fluorocarbon copolymer/TEOS is the strongest but has poorer softness. Furthermore, when processing with chemical compounds, the processes or orders had little effect on the fabric's angle of contact and bleaching, but had more significant influence on strength. Regarding to washing fastness, after ten‐time water washing, the angle of contact of processed fabrics decreased by about 3%. Overall, the fabric pretreated with TEOS, followed by fluorocarbon polymer, had the best balance of physical properties. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3019–3024, 2007     

Differential adsorption of heavy metal ions by cotton stalk cation‐exchangers containing multiple functional groups

Esterification of cotton stalks with chlorosulfonic acid, phosphorus oxychloride, and their mixture was carried out with the aim to prepare cation exchangers for the removal of heavy metal ions from industrial waste water. Elemental analysis, Fourier transform infrared (FTIR) analysis, and sodium ions binding capacity were used to prove the occurrence of the esterification. The efficiency of the prepared cation exchangers to remove some heavy metal ions (strontium, arsenic, copper, and nickel) at different metal ion concentration, pH, contact time, and temperature was studied. The results showed that cotton stalks that contain both phosphate and sulfonate groups (phosphosulfonated cotton stalks) showed higher adsorption of the different heavy metal ions than cotton stalks containing sulfonate or phosphate on a separate basis. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 4124–4132, 2006     

活性污泥对废水中铍的吸附与解吸

本文研究了活性污泥对水中铍的吸附特性。考察了时间、温度、pH、共存离子等对吸附过程的影响，以及吸附过程中溶液pH的变化规律，研究结果表明：铍在污泥上的吸附主要为快速的表面吸附，受温度影响不大，在pH3—7范围，吸附量随pH的升高而增大，铜、铅、锌、钙由于共同竞争吸附电位而使吸附量下降，铁、铝等由于产生微沉淀而致使吸附量增加，钠由于具有竞争和生成复盐双重作用导致吸附量交叉变化，硫酸根和磷酸根由于与铍生成沉淀而增加去除率，而氟和铍生成稳定配离子使去除率下降，溶液pH由于生成配离子而呈现反常的升高；此外，还探讨了不同解吸刑对污泥中铍的解吸效果，结果表明，盐酸解吸效果最佳，解吸率高达96．73％。     

Infrared spectroscopic studies of the nonformaldehyde durable press finishing of cotton fabrics by use of polycarboxylic acids

A number of polycarboxylic acids have been used successfully as new nonformaldehyde cross-linking agents for cotton fabrics. In our previous research, Fourier transform infrared photoacoustic spectroscopy (FTIR/PAS) demonstrated the ability for characterizing ester cross-linkages in the finished cotton fabrics. In this research, the effects of different acid concentrations, different catalyst concentrations, different curing temperatures, and different curing times on the ester cross-linking of the cotton fabrics were determined by FTIR/PAS. The infrared spectroscopic data were also correlated to durable press (DP) ratings. FTIR appears to be useful for evaluating the effectiveness of polycarboxylic acids as cross-linking agents for cotton fabrics. FTIR definitely complements the existing methods for evaluating finished textile fabrics.     

涤棉织物化学回收工艺研究

以废旧涤棉织物为原料,乙二醇(EG)为醇解剂,通过改变醇解时间、醇解温度、EG/废旧涤棉织物中聚对苯二甲酸乙二醇酯(PET)质量比(mEG/mPET)、催化剂种类及用量等研究了蓬松态下废旧涤棉织物的醇解工艺,以及醇解过程对涤棉织物中棉纤维性能的影响。结果表明:随着醇解时间、醇解温度的提高,mEG/mPET的增大,涤棉织物的醇解程度增大,各参数达到一定程度后醇解程度基本不变;最佳醇解工艺为涤棉织物中mEG/mPET为2/1,催化剂用量为涤棉织物中PET质量的0.30%,醇解温度196℃,醇解时间1 h;在乙酸锌、碳酸钠、乙酸钾、氯化镁4种催化剂中,碳酸钠综合催化效果最佳;经醇解过程后涤棉织物中棉纤维表面变得粗糙,力学性能有较大下降。     

Chitosan Functionalized with Carboxyl Groups as a Recyclable Biomaterial for the Adsorption of Cu (II) and Zn (II) Ions in Aqueous Media

The modification of chitosan represents a challenging task in obtaining biopolymeric materials with enhanced removal capacity for heavy metals. In the present work, the adsorption characteristics of chitosan modified with carboxyl groups (CTS-CAA) towards copper (II) and zinc (II) ions have been tested. The efficacy of the synthesis of CTS-CAA has been evaluated by studying various properties of the modified chitosan. Specifically, the functionalized chitosan has been characterized by using several techniques, including thermal analyses (differential scanning calorimetry and thermogravimetry), spectroscopies (FT-IR, XRD), elemental analysis, and scanning electron microscopy. The kinetics and the adsorption isotherms of CTS-CAA towards both Cu (II) and Zn (II) have been determined in the aqueous solvent under variable pH. The obtained results have been analyzed by using different adsorption models. In addition, the experiments have been conducted at variable temperatures to explore the thermodynamics of the adsorption process. The regeneration of CTS-CAA has been investigated by studying the desorption process using different eluents. This paper reports an efficient protocol to synthesize chitosan-based material perspective as regenerative adsorbents for heavy metals.     

Chitosan phosphate induced better thermal characteristics to cotton fabric

Chitosan phosphate was prepared and applied at different concentrations with and without low formaldehyde N‐methylol finishing agent (resin) to cotton fabrics. Chitosan phosphate was characterized by FTIR, nitrogen content, and phosphorus content. The so‐treated fabrics were monitored for thermogravimetric analysis (maximum decomposition temperature and residue contents after decomposition), nitrogen content, phosphorus content, tensile strength, and elongation at break. Results indicate that extent of reaction of chitosan phosphate with the cotton fabric relies on concentration of the former; increasing the concentration of the resin has practically no effect on this reaction though the resin functions as a chemical bridge between the chitosan phosphate and the cotton fabric. On the other hand, the nitrogen of the resin and the phosphorus of chitosan undergo synergetic effect and enhance the thermal properties of the treated cotton. Strength properties display higher values in the presence than in the absence of chitosan phosphate when the latter was used along with the resin. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2021–2026, 2007     

Application of DMEU/SiO2 gel solution in the antiwrinkle finishing of cotton fabrics

In this experiment, cotton fabrics were treated by padding, drying, and curing with an antiwrinkle finishing reagent, dimethylolethylene urea (DMEU), in combination with different concentrations of tetraethoxysilane (TEOS) and isopropanol (IPA) at various volumes. The treated fabrics were studied to determine the effects of adding TEOS and IPA. They were also analyzed using Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) methods to examine the binding between SiO₂ and DMEU. The results showed that hydrogen bonds formed between SiO₂ and DMEU. TEOS was found to improve the antiwrinkle properties, tensile strength retention, and yellowing of the treated fabrics, although their softness was slightly reduced. The solvent IPA was shown to decrease the tensile strength of treated fabrics, although it improved their antiwrinkle properties. We observed only one stage of pyrolysis in untreated cotton fabrics, whereas the treated fabrics showed two stages. In addition, the fabrics treated with TEOS showed improved heat resistance. Our findings demonstrated that cotton fabrics showed excellent antiwrinkle properties and high tensile strength, when treated with a finishing solution composed of DMEU, 3% TEOS, IPA and water, followed by predrying and curing. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4136–4143, 2006     

Conductive Cotton Fabrics Coated with Myristic Acid/Zinc Oxide Nanoparticles

This research mainly deals with enhancement of electrical conductivity performance of cotton fabrics using zinc oxide nanoparticles. The application of nano-zinc oxide/myristic acid onto 100% cotton plain fabrics was performed by dipping process. The effect of myristic acid and zinc oxide nanoparticles on cotton fabrics was analyzed by Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy. Electrical conductivity, UV protection performance, and hydrophilic properties of the cotton fabrics were also investigated. The surface resistivity of the cotton fabric noticeably dropped off by applying nano-zinc oxide/myristic acid. Furthermore, electrical conductivity of the coated cotton fabrics was maintained till 15 weeks. Surface hydrophilicity of cotton fabrics decreased with increasing myristic acid content. The changes in decomposition temperatures and crystallinity can be ignorable after application of myristic acid/nano-zinc oxide.     

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     

Preparation and properties of chitosan/poly(vinyl alcohol) blend foams for copper adsorption

A new form of polymer blend, macroporous chitosan/poly(vinyl alcohol) (PVA) foams made by a starch expansion process, exhibits the functionalities of chitosan while avoiding its poor mechanical properties and chemical instabilities. The appropriate conditions for foaming are discussed using both insoluble and water‐soluble chitosan. The chitosan/PVA foams demonstrated interconnected and open‐cell structures with large pore size from tens to hundreds of micrometers and high porosities from 73.6 to 84.3%. Glutaraldehyde was employed to improve the retention of chitosan and copper adsorption of the chitosan/PVA foams. While it increased the retention of chitosan and the adsorption capacities, glutaraldehyde decreased the pore size and porosity. The macroporous structure of the chitosan/PVA foams indicates extensive application prospects in terms of the considerable adsorption of heavy metal ions. Copyright © 2006 Society of Chemical Industry