Aiqin Gao

Flame retardant finishing of cotton fabric based on synergistic compounds containing boron and nitrogen.

Boric acid and compound containing nitrogen, 2,4,6-tri[(2-hydroxy-3-trimethyl-ammonium)propyl]-1,3,5-triazine chloride (Tri-HTAC) were used to finish cotton fabric. The flame retardant properties of the finished cotton fabrics and the synergetic effects of boron and nitrogen elements were investigated and evaluated by limited oxygen index (LOI) method. The mechanism of cross-linking reaction among cotton fiber, Tri-HTAC, and boric acid was discussed by FTIR and element analysis. The thermal stability and surface morphology of the finished cotton fabrics were investigated by thermogravimetric analysis (TGA) and scanning electron microscope (SEM), respectively. The finishing system of the mixture containing boron and nitrogen showed excellent synergistic flame retardancy for cotton fabric. The cotton fabric finished with mixture system had excellent flame retardancy. The LOI value of the treated cotton fabric increased over 27.5. Tri-HTAC could form covalent bonds with cellulose fiber and boric acid. The flame retardant cotton fabric showed a slight decrease in tensile strength and whiteness. The surface morphology of flame retardant cotton fiber was smooth.

Preparation of the superhydrophobic nano-hybrid membrane containing carbon nanotube based on chitosan and its antibacterial activity

The functional nano-hybrid surface containing multi-walled carbon nanotubes (MWCNT) on chitosan incorporated with the cationic chitosan (C-CS), MWCNTs and silicon couple agent (KH-560) was designed and prepared. The nano-hybrid membranes (NHM) containing MWCNTs were modified by perfluorooctanesulfonyl fluoride (PFOSF). The superhydrophobic multi-functional membranes with biological activity and superhydrophobic surface were obtained. The incorporated MWCNTs improved the roughness of the nano-hybrid membranes. The perfluorinated end groups of the nano-hybrid membrane surface provided low energy surface. The antibacterial activity, surface superhydrophobicity and mechanical property of the perfluorinated nano-hybrid membranes (PFNM) were discussed. Their morphological structures and surface ingredients were characterized by energy dispersive X-ray spectrometer (SEM-EDX). The PFNMs had excellent antibacterial property and superhydrophobicity. The novel nano-hybrid membranes with excellent antibacterial, superhydrophbic, and mechanical properties have potential applications in the food engineering, bioengineering fields and medical materials.

Printing properties of the red reactive dyes with different number sulfonate groups on cotton fabric

Cellulose fabric is an important printing substrate. Four red azo reactive dyes based on 1-naphthol-8-amino-3,6-disulfonic acid for cotton fabric printing were designed. Their UV-Vis spectra and printing properties for cotton were investigated. The relationship between the chemical structures of the dyes and their printing properties on cotton fabric was discussed. The results show that the color yield (K/S) values of the printed fabrics decreased with the increase of sulfonate groups, but the fixation and penetration of the reactive dyes on cotton fabric increased. The reactive dyes with fewer number sulfonate groups were sensitive to alkaline and urea. Whereas, the reactive dyes with numerous sulfonate groups were not sensitive to urea and had good leveling properties, penetration uniformity, and good wet fastness for cotton fabric. Surface wettability of all cotton fabrics printed with four dyes was excellent. It is possible to print cotton fabric urea-free using the reactive dyes with numerous sulfonate groups.

Preparation of multi-functional cellulose containing huge conjugated system and its UV-protective and antibacterial property.

A novel Schiff base containing huge azo conjugated system and reactive groups, 3,5-bis{2-hydroxyphenyl-5-[(2-sulfate-4-sulfatoethylsulfonyl-azobenzol)methylene amino]}benzoic acid (BHSABA) was applied to modify cellulose. Exhaustion and grafting reactive rate, and grafting quantity of BHSABA on cellulose were calculated. The chemical structure of the modified cellulose was characterized and thermal degradation and morphology were also investigated. The UV protection and antibacterial properties were measured. With increasing the concentration of BHSABA, grafting quantity of BHSABA on cellulose increased from 1.52 × 10(-2)mmol/g to 5.08 × 10(-2)mmol/g. The multi-functional cellulose fabrics had excellent UV-protective property, which possessed very high UPF value and very low ultraviolet transmittance. The UPF values exceeded 50 and the ultraviolet transmittances were all less than 1%. They also exhibited moderate activity against Staphylococcus aureus and after 10 times washing still maintained antibacterial activity. The onsets of degradation slightly decreased. With increasing the grafting quantity of BHSABA on cellulose, mass loss yields of the residues increased. The morphological structure had no noticeable change.

Dyeing performance of the azo dyes containing trifluoromethyl group for polyester fabrics and its single crystal structure

The structures of disperse dyes and their intermolecular interactions have important impacts on dyeing and printing performances for polyester fabrics. The fluorine dyes show some unique molecular stability and photochemical properties. The dyeing property of the azo dye containing trifluoromethyl group for polyester fabrics, 4-(N-acetoxyethyl-Nethyl)- amino-2-bromine-4-nitro-6-trifluoromethylazo- benzene (D1), was investigated and compared with the similar structure disperse dye. The results show that the high color yield and good exhaustion of the dyed PET fabrics could be obtained. The polyester fabrics dyed with D1 had excellent light fastness. Its single crystal was prepared and the supramolecular interactions were solved by X-ray diffraction. Dye D1 formed triclinic crystals in a trimeric packing mode. The C-F bond distances of CF3 are 1.2730 Å, 1.2240 Å and 1.2900 Å, respectively. The two benzene rings linked azo unit (-N=N-) are obviously twist. The dihedral angle of the two benzene rings is 50.23 o. There are six weak hydrogen bonds around trifluoromethyl group in the intramolecule and intermolecule. The excellent light stability of the dye should be attributed to its unique supramolecular structure.

Assembly of transition metal ion on cellulose surface anchored with azo-Schiff base and its catalytic activity for H2O2 decomposition

AbstractTo form polymer-supported catalysts, to eliminate excess H2O2 during wastewater treatment, the assembly of metal ion on cellulose was investigated. Cellulose was covalently grafted with reactive azo-Schiff base containing azo-conjugated system, 3,5-bis {2-hydroxyphenyl-5-[(2-sulfate-4-sulfatoethylsulphonyl-azobenzol) methylene amino]} benzoic acid. Metal ions, Co2+, Mn2+, and Cu2+, were anchored to the modified cellulose by controlling assembly. The cellulose-supported complexes were characterized and the catalytic activity for H2O2 was investigated. Elemental analyses of the cellulose supported complexes, MC–Co, MC–Mn, were well agreed with the proposed composition. Three cellulose-supported complexes had strong catalytic activities for H2O2. H2O2 decomposition rates in 10xa0min were 84.54% for MC–Co, 94.87%, for MC–Mn, and 77.21% for MC–Cu, respectively. The manganese complex had the strongest catalytic activity among them. The cellulose-supported complexes have potential application in wastewater...

Functional modification of cellulose fabrics with phthalocyanine derivatives and the UV light-induced antibacterial performance

Cellulose fabrics were modified with a derivative of copper phthalocyanine (Reactive Blue C.I. 21) by dyeing method. The modified cellulose fabrics exhibited important photoactive property, such as the hydroxyl radicals-generating ability. The UV-vis spectrum, exhaustion rate, fixation rate and grafting quantity of Reactive Blue 21 on the cellulose fabrics were measured and calculated. The chemical structure and morphology of the modified cellulose were characterized. The amount of the produced hydroxyl radicals was measured and the photoactive mechanism was discussed. The UV light-induced antibacterial performance of the modified materials was measured. The modified cellulose exhibited photo-induced antibacterial activity against both Staphylococcus aureus and Escherichia coli.

Crosslinking formulations based on novel reactive disperse dyes for printing cotton fabrics

Cotton cellulose is an excellent natural material due to its outstanding characters. Five novel crosslinking reactive disperse dyes containing bi-functional groups, two 3-chloro-2-hydroxypropyl groups, were synthesized and characterized by infrared spectroscopy, proton magnetic resonance spectroscopy and element analysis. The solvent effect on the color of the dyes was assessed by the electronic absorption spectra. The crosslinking printing properties of the five dyes (D1–5) for cotton fabrics were investigated. The electronic absorption property exhibited larger bathochromic shifts in a stronger polar solvent than in the weaker polar solvents. The crosslinking reaction between two 3-chloro-2-hydroxypropylreactive groups and the hydroxyl group of cellulose could take place. The higher color yield and excellent fixation were obtained. The building up property was good for all the dyes on cotton fabric. The printed samples had excellent washing, perspiration and rubbing fastness. The light fastness for cotton fabrics was moderate.

Dyeing properties of the disperse dyes containing cyano group based on benzisothiazole for polyester fabrics under alkali condition

One step dyeing of polyethylene terephthalate (PET) fabrics combining pretreatment and dyeing under the alkali condition was developed for cleaner production. One step dyeing of PET fabrics required that the dye used has good acid and alkali stability. In this paper, dyeing properties of three azo disperse dyes containing cyano group based on benzisothiazole, 3- (4-N-ethoxyl-N-cyanoethyl -phenyldiazenyl)-5-nitro-2,1-benzisothiazole (D1), 3-(4-N-ethyl-N-cyanoethyl- phenyldiazenyl)- 5-nitro-2,1-benzisothiazole (D2), and 3-(N-benzyl-N-cyanoethyl- phenyldiazenyl)-5-nitro-2,1-benzisothiazole (D3), were investigated under alkali condition. The results showed that polyester fabrics could be well dyed with D1, D2 and D3 under the acid condition. However, D1 was decomposed while dyeing at the alkali solution. D2 and D3 had excellent color yields under the alkali condition. The acid-alkali stability and the structure change were analyzed by UV-vis spectrum and high pressure liquid chromatography (HPLC). Gaussian 09 program package was used to optimize geometry by B3LYP method and 6-31G (d) basis set. The solvation energy of D1 in water was higher than those of D2 and D3. The electron withdrawn effect of the hydroxyl affected the energy gap of HOMO and LUMO orbits. D2 and D3 showed excellent stability in the strong alkali medium. And the dyed polyester fabrics with D2 and D3 at the alkali condition also had good fastness properties.