Organometallic Magnesium Complex with Aggregation Induced Emission Properties: Synthesis, Characterization, and Fluorescent Fibers Applications.

In this work, a novel organomagnesium complex with outstanding aggregation induced emission (AIE) properties is synthesized using dibenzoylmethane (DBM) as the ligand. The structure of the complex is confirmed to be one magnesium ion coordinated to the dione groups of two DBM molecules, and the magnesium ion adopts a distorted octahedrally geometry. The obvious emission is found for Mg(DBM)2 powder and not in the solution, making this the first reported organomagnesium complex with AIE property. The properties of the complex were investigated by using UV-vis absorption and fluorescence emission spectroscopy, cyclic voltammetry, and density functional theory calculations. Moreover, the Mg(DBM)2 solution dispersed in filter paper was is colorless, which may be made into a convenient anti-counterfeiting and encryption tool. Mg(DBM)2 /alginate fibers were prepared by wet-spinning process and further processed into paper, which can be used in the fields of sensors, anti-counterfeiting, and encryption. Sweat contains a wealth of chemical information that could potentially indicate the body's deeper biomolecular state. The prepared fluorescent fibers were used to detect sweat due to its non-toxic, low-cost efficient and fast response to analytes.

Removing the residual cellulase by graphene oxide to recycle the bio-polishing effluent for dyeing cotton fabrics.

In this research, a stable graphene oxide (GO) suspension was prepared by chemical reduction method from graphite powder. By TEM, the irregular GO sheets with single-atom-layered structure could be observed. The zeta potentials measurement indicated the surface charges of GO were strongly related to pH. BET analysis showed the GO had a specific surface area of 30.7 m2/g and pore volume of 0.10 cm3/g. When the GO was used to remove the residual cellulase in bio-polishing effluent, it was found the removal capacity reached its maximum value at the pH 4-5. The kinetics studies showed that the removal process of cellulase followed a pseudo-second-order kinetic model with a rate constant (k2) of 0.276 × 10-3 g/mg min and equilibrium adsorption capacity of 278.55 mg/g, respectively. By plotting the adsorption isotherms, it was found the Langmuir model fitted the experimental data well with a cellulase adsorption capacity of 574.71 mg/g, indicating the adsorption of cellulase by GO in a monolayer manner. When dyeing the cotton fabrics with reactive dyes, it was found that the cotton fabrics could acquire similar color properties in the recycled bio-polishing effluent as in fresh water, meaning the effectiveness of removing cellulase by GO and the feasibility of recycling the bio-polishing effluent.

In-situ synthesis of polypyrrole/silver for fabricating alginate fabrics with high conductivity, UV resistance and hydrophobicity.

In this research, the polypyrrole/silver (PPy/Ag) composite was first in-situ prepared on alginate fabrics by chemical oxidative polymerization of pyrrole (Py) monomer using silver nitrate as oxidant and sodium dodecyl sulfate (SDS) as the dopant. The effects of mole ratio of Py to silver nitrate, reaction time and dopant concentration on the preparation of PPy/Ag composite were optimized. It was found the optimal molar ratio of Py to silver nitrate was 1:1.5 with 0.02 M SDS under the reaction time of 10 h. Then, the microstructure and properties of resultant PPy/Ag composite were analyzed by scanning electron microscope (SEM), Fourier infrared spectrometer (FT-IR), X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and the thermogravimetry analysis (TGA), respectively. Finally, the influences of PPy/Ag coating on the performance of alginate fabrics including electrical conductivity, hydrophilicity, antistatic property and anti-ultraviolet capability were determined. It was found that the electrical conductivity of alginate fabric could be intensively increased after PPy/Ag coating. Meantime, the anti-ultraviolet capability and hydrophobicity could be largely improved by PPy/Ag coating especially under high Py dosage. This paper introduced a simple method for preparing PPy/Ag composite direct on alginate fabric to make it a good functional substrate which could be applied in many fields.

Investigating the synergetic dispersing effect of hydrolyzed biomacromolecule Cellulase and SDS on CuPc pigment.

In this paper, the dispersion performance of biomacromolecule hydrolyzed cellulase from Trichoderma reesei on copper phthalocyanine (CuPc) pigment was first studied. The effect of hydrolysis time, cellulase concentration and environmental pH on the dispersion performance was investigated by particle size distribution and suspension transmittance measurement. The hydrolysis degree of cellulase was determined by FTIR, XRD, UV-vis and fluorescence spectra, potential and particle size analysis, respectively. Subsequently, the hydrolyzed cellulase was combined with sodium dodecyl sulfate (SDS) for acquiring better CuPc suspension based on their synergetic effects on dispersion. The optimal mass ratio of hydrolyzed cellulase to SDS was found to be 1:9. The resulting CuPc dispersion by this hydrolyzed cellulase/SDS composite was characterized by FTIR, TG, TEM, XRD analysis, respectively. This study demonstrated that there were strong interactions between hydrolyzed cellulase and SDS to result in synergistic dispersing effect on CuPc for better stability.

Controlled synthesis of sodium alginate electrospun nanofiber membranes for multi-occasion adsorption and separation of methylene blue.

Herein, the three kinds of water-insoluble alginate-based nanofiber membranes were prepared by electrospinning and followed with crosslinking by calcium chloride (CaCl2), glutaraldehyde vapor (GA), and trifluoroacetic acid (TFA) crosslinking, respectively. All the sodium alginate(SA) nanofiber membranes present excellent integrated adsorption performance toward methylene blue (MB). Among these, CaCl2 crosslinked SA membranes exhibit the maximum actual adsorption capacity of 2230 mg/g and shortest adsorption equilibrium time of 50 min to date. On the basis of the selective adsorption of SA, the nanofiber membranes can separate MB/ methyl orange (MO) mixture solution and maintain high separation efficiency even after five cycles. In addition, respective applicable condition for differentially crosslinked SA nanofiber membranes was evaluated. The TFA crosslinked membranes have the least reduction in the adsorption capacity in acidic environment and GA crosslinked membranes adsorb better in alkaline environment. For seawater environment, GA crosslinked membranes show obvious adsorption performance than other crosslinked membranes.

Inkjet Printable and Self-Curable Disperse Dyes/P(St-BA-MAA) Nanosphere Inks for Both Hydrophilic and Hydrophobic Fabrics.

Low-water-soluble disperse dyes possess a broad color gamut and good durability, but they need chemical or physical modification before being used in inks and can only be applied to several kinds of hydrophobic fabrics. In this work, disperse dyes/P(St-BA-MAA) nanospheres (known as DPN) absorbed by sodium nitrilotriacetate (known as NTA@DPN) were prepared and applied into ink formulations, which exhibited high dye fixation, long-term stability and self-curable ability without addition of any binder. Transmission electron microscopy (TEM) images showed the nanospheres have homogeneous core-shell spherical shape and the average diameter increased by 20.6 nm after coloration. X-ray diffraction (XRD), Fourier transform infrared spectrum (FTIR), and differential scanning calorimetry (DSC) measurements illustrated the interaction between dyes and nanospheres and indicated that the colored nanospheres contained both dye molecules and crystalline dyes. The Zeta potential and particle size measurements demonstrated that the dispersion stability was improved when sodium nitrilotriacetate (NTA) was absorbed onto DPN. The rheological behavior of the NTA@DPN inks was Newtonian and desired droplet formation was achieved at the viscosity of 4.23 mPa·s. Both hydrophilic cotton and hydrophobic polyester fabrics were cationic modified before used, which had an excellent image quality and desired rubbing fastness after inkjet printing. Scanning electron microscope (SEM) images showed NTA@DPN formed stable deposits on the surface of modified fibers and could self-cure to form continuous film coating on the fiber surface after being baked at 150 °C without addition of any binder.

In Situ Electrospinning Iodine-Based Fibrous Meshes for Antibacterial Wound Dressing.

For effective application of electrospinning and electrospun fibrous meshes in wound dressing, we have in situ electrospun poly(vinyl pyrrolidone)/iodine (PVP/I), PVP/poly(vinyl pyrrolidone)-iodine (PVPI) complex, and poly(vinyl butyral) (PVB)/PVPI solutions into fibrous membranes by a handheld electrospinning apparatus. The morphologies of the electrospun fibers were examined by SEM, and the hydrophobicity, gas permeability, and antibacterial properties of the as-spun meshes were also investigated. The flexibility and feasibility of in situ electrospinning PVP/I, PVP/PVPI, and PVB/PVPI membranes, as well as the excellent gas permeabilities and antibacterial properties of the as-spun meshes, promised their potential applications in wound healing.

The synchronized wash-off of reactive-dyed cotton fabrics and decolorization of resultant wastewater using titanium dioxide nano-fibers.

In this research, titanium dioxide (TiO2) nano-fibers with a well-organized anatase structure were synthesized by a hydrothermal method. Their structural properties were characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), and transmission electron microscope (TEM) analysis, respectively. Subsequently, the TiO2 nano-fibers were optically excited under the ultraviolet (UV) irradiation to decolorize the reactive dye solution. The influences of initial pH, concentrations of reactive dye and TiO2 nano-fibers as well as irradiation time on rate of photocatalytic decolorization were investigated. Based on their excellent photocatalytic performance, a novel method for achieving the synchronized wash-off of reactive-dyed cotton and decolorization of resultant wastewater was developed. It was found that the wash fastness of reactive-dyed cotton after TiO2-based wash-off was equal to that after standard way. The influences of TiO2-based wash-off on the properties of cotton substrates were determined by Fourier transform infrared spectroscopy (FTIR), XRD, and scanning electron microscope (SEM) analysis, respectively, which indicated that this new synchronized method would exert few damages to the cotton substrate.

Ultrasonic effect on the desizing efficiency of α-amylase on starch-sized cotton fabrics.

Enzymatic desizing by α-amylase and ultrasound irradiation are the two important clean technologies in the textile industry. In the present work, with the aim of giving a further insight to the influence of ultrasound on α-amylase activity and its desizing efficiency, the ultrasound-based experiments were afforded in two ways: (i) step-wise treatment of α-amylase by ultrasound and then enzymatic desizing, as well as; (ii) simultaneous utilization of ultrasound and α-amylase for the desizing. By the step-wise strategy, it is found that the ultrasound has negative impact on the α-amylase activity using soluble starch as substrate. However, the sonicated α-amylase possesses higher desizing efficiency because there are higher hydrophobic interactions between sonicated α-amylase protein and starch-sized cotton and thus intensifies its catalytic activity. By the simultaneous procedure, the enhancement to desizing efficiency is more pronounced than that by the step-wise procedure. This can be attributed to comprehensive actions of several reasons such as more effective stirring/mixing mechanism, damages or changes to substrate, more effective catalysis to hydrolytic reactions and faster removal of loosened products from the fabric bulk.

The adsorptive and hydrolytic performance of cellulase on cationised cotton.

In this research, the cotton fabrics were cationised by a cationic agent to change their surface electric properties. The cationised cotton fabrics were then bio-polished by cellulase to explore the influence of cationisation on the adsorptive and hydrolytic performance of cellulase. The experimental results from cellulase adsorption reveal the cationisation of cotton can obviously improve the binding efficiency of cellulase protein mainly by the improved electrostatic attraction between oppositely charged cellulase and cationised cotton. The adsorption parameters calculated can further prove this improvement trend. Through measuring the concentration of reducing sugars released and weight loss of cotton during the bio-polishing, it is found the hydrolytic activity toward cotton is partially damaged by the cationisation. The reason can be attributed to the movement restriction and dysfunction of cellulase protein by the cationisation.

Ultrasound-assisted adsorption of anionic nanoscale pigment on cationised cotton fabrics.

Application of pigments in textile coloring has many advantages such as less water and energy consumption, less effluent load and higher efficiency, so the pigments are perfect alternatives to dyes for eco-friendly coloring. In this work, a stable anionic nanoscale pigment suspension was prepared using a polymeric dispersant to color the cationised cotton with the exhaust method. Meanwhile, ultrasound was carried out during the adsorption to evaluate the ultrasonic influences on the uptake of pigment, adsorption efficiency and final product quality. The uptake of pigment is found to be higher with ultrasonic method than that with conventional technique because of the good dispersing capacity of ultrasound to pigment particles. Besides, it is found that nanoscale pigment has higher adsorption rate when using ultrasonic method because the ultrasound promotes the diffusion of pigment through the fiber-liquid boundary layer. Lastly, the color difference (ΔE) reveals the nanoscale pigment can be deposited on cotton surface more uniformly under ultrasonic condition, improving the product quality obviously.