Shouxiang Jiang

Covalently functionalized graphene with D-glucose and its reinforcement to poly(vinyl alcohol) and poly(methyl methacrylate)

Chemically functionalized graphene has been synthesized by covalently grafting D-glucose on graphene for the first time through an esterification reaction. The D-glucose functionalized graphene was further applied in the preparation of poly(vinyl alcohol) and poly(methyl methacrylate) nanocomposites. The thermal and mechanical properties of the prepared nanocomposites were then investigated. It was demonstrated that the D-glucose was grafted on the surface of the graphene through a covalent attachment. The chemically functionalized graphene had better dispersibility in both water and dimethylformamide than the pristine graphene. The better dispersion of the functionalized graphene in both aqueous and organic solvents simplified the preparation of the polymer nanocomposites. It was found that the D-glucose grafted graphene dispersed homogeneously in both poly(vinyl alcohol) and poly(methyl methacrylate) matrices, increasing the thermal and mechanical properties of the polymers at the same time. The phenomena were ascribed to the introduction of the D-glucose, which induced strong hydrogen bonding interactions between the functionalized graphene and the polymers. The results of this study indicate that this is an effective approach for preparing well-dispersed graphene-based polymer nanocomposites by covalently attaching functional molecules on the surface of graphene.

Fabrication of 3D Polypyrrole/Graphene Oxide Composite Hydrogels with High Performance Swelling Properties

Abstract The polypyrrole (PPy)/graphene oxide (GO) composite hydrogels with hierarchical porous structures were fabricated by one-step self-assembly method. The static oxidation polymerization of pyrrole monomer in GO aqueous solution resulted in the formation of three-dimensional (3D) PPy/GO composite hydrogels, which consisted of one-dimensional PPy nanofibers and two-dimensional GO nanosheets. The as-prepared composite hydrogels exhibited shrinking–swelling behavior with cycles of suction and water-supplying. The effects of GO nanosheets content on the swelling properties were investigated. Results showed that the well-dispersed GO nanosheets in the hydrogel networks resulted in a significant improvement in water absorbencies of the hydrogels. PPy/GO composite hydrogels exhibited unobvious variation in the water absorbency even in saline solutions. Such excellent properties in water absorbencies endow the conducting 3D PPy/GO composite hydrogels with great potential applications in electrochemical sensors or controlled release.

Microstructure and photoluminescent properties of Y2O3:Eu3+ phosphors synthesised by precipitation and combustion methods

Abstract Y2O3:Eu3+ phosphors were prepared by NH4HCO3 based precipitation method and C2H5NO2–nitrate solution combustion synthesis method respectively. The phosphors were systematically investigated by field emission scanning electron microscope (SEM), X-ray diffractometer (XRD), scanning electron microscope (XPS) and fluorescence spectrometer. Luminescent properties of Y2O3:Eu3+ phosphors synthesised by two different methods were also compared. The results show that Y2O3:Eu3+ phosphor prepared by precipitation technique is spherical with nanometre particle size from 55 to 60 nm, whereas the one synthesised by combustion technique exhibits extensive sheet porosity structure. X-ray diffraction spectra indicate that both of the samples have pure cubic phases and the crystallinity of phosphor synthesised by combustion technique is improved. The main emission peaks of Y2O3:Eu3+ phosphors at 613 nm are due to the 5D0–7F2 transition of Eu3+ ions, and phosphor obtained by precipitation method shows higher emission intensity. The results reveal that Y2O3:Eu3+ phosphor with spherical particle shape can exhibit good luminescent properties and morphology of Y2O3:Eu3+ phosphor is a more crucial factor than crystal structure to the enhanced luminescence.

Microwave-assisted coating of silver nanoparticles on bamboo rayon fabrics modified with poly(diallyldimethylammonium chloride)

Silver nanoparticles were coated on bamboo rayon fabrics (fabrics made from filaments of dissolved and regenerated bamboo pulp fibers) modified with poly(diallyldimethylammonium chloride) (PDDA) under microwave radiation. The silver nanoparticle coated bamboo rayon fabrics modified with PDDA were characterized by fourier transform infrared spectroscopy, X-ray diffraction, energy dispersive X-ray spectroscopy, atomic force microscope and scanning electron microscope. Color properties, ultraviolet (UV) protection, softness and contact angle of the silver nanoparticle coated bamboo rayon fabrics were evaluated. The results show that PDDA is successfully modified on the bamboo rayon fabric. Compared with the bamboo rayon fabrics without PDDA modification, more silver nanoparticles are coated on the bamboo rayon fabrics modified with the PDDA. In addition, the bamboo rayon fabric modified with PDDA is evenly covered with silver nanoparticles. The silver nanoparticle coated bamboo rayon fabric modified with PDDA shows the excellent UV protection with UPF of 223.88 and the hydrophobic property with contact angle of 127°. PDDA modification improves the adhesive strength between silver coating and bamboo rayon fabric.

Influence of annealing temperature on microstructure and luminescent properties of Y2O3: Eu3+ deposited quartz fibre

In this study, Eu3+ doped Y2O3 (Y2O3: Eu3+) phosphor target was deposited on quartz fibre substrates by electron beam evaporation technology, and then the deposited fibres were annealed at different temperatures from 600 to 1000°C. Particle shape was changed, and particle size of Y2O3: Eu3+ was increased with the rise in annealing temperature. Crystallisation and luminescent intensity of the deposited films on quartz fibres were significantly improved by annealing treatment. The most effective crystallisation and the maximum luminescent efficiency of the thin films were obtained when the deposited fibres were treated at 1000°C for 1 h. The luminescent property results indicated that the particle shape, particle size and crystallisation were the important factors affecting luminescent intensity of the deposited fibres.

Preparation of silver/reduced graphene oxide coated polyester fabric for electromagnetic interference shielding

In this study, silver/reduced graphene oxide (Ag/RGO) coated polyester (PET) fabrics with dopamine as adhesive agent were prepared through an efficient chemical reduction method under microwave irradiation. The as-synthesized samples were characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and scanning electron microscopy. Deposit weight, surface resistance and electromagnetic interference (EMI) shielding effectiveness (SE) of the Ag/RGO coated PET fabric were investigated. The dopamine modified PET fabric is covered with silver particles and reduced graphene oxide (RGO) sheets uniformly and densely. In addition, the Ag/RGO coated fabric possesses high electrical conductivity with low surface resistance of 0.678 Ω sq−1 and EMI SE of Ag/RGO coated fabric ranges from 58 dB to 65 dB in the range of 1–18 GHz X-band. Adhesive strength between Ag/RGO particles and PET fabric is significantly improved.

Synthesis of silver nanoparticles on bamboo pulp fabric after plasma pretreatment

Silver nanoparticles were synthesized on bamboo pulp fabric with pretreatment of plasma under microwave radiation. The silver nanoparticles coated bamboo pulp fabrics were characterized by Fourier transform infrared spectroscopy, scanning electron microscope, thermogravimetric analysis and X-ray diffraction. Color characteristics and contact angles of silver coated bamboo pulp fabrics were evaluated. Adhesive strength of silver nanoparticles on bamboo pulp fabrics without and with pretreatment of plasma was investigated. Compared with silver nanoparticles coated bamboo pulp fabric without pretreatment of plasma, more silver nanoparticles are coated on the bamboo pulp fabric with pretreatment of plasma. Bamboo pulp fabrics are evenly covered with silver nanoparticles with pretreatment of plasma. In addition, influences of distance between the plasma source and the fabric and treating time on deposition amounts of silver nanoparticles were investigated. Color strength values decrease and increase with the rise of distance and treatment time, respectively. The silver nanoparticles coated bamboo pulp fabric pretreatment of plasma has excellent UV protection, good fastness to laundering and hydrophobicity.

Foam Dyeing for Developing the Wash-out Effect on Cotton Knitted Fabrics with Pigment

In this study, the foam dyeing technology was applied to dye cotton knitted fabric for achieving the surface-dyed result. The T-shirt made by this surface-dyed fabric could easily obtain the wash-out effect after garment laundering. The pigment dyeing performances in foam dyeing were system studied. Colour strength, colourfastness and serviceability of fabrics dyed with the methods of foam-padding and liquid-padding were evaluated and compared. Results show that surface dyeing for cotton-knitted fabric with foam media could overcome the shortcoming of poor penetration in foam dyeing method, and turn the poor penetration into the superiority for obtaining the surface-dyed result. The serviceability such as water absorption and handle property was also well improved in foam dyeing method. Finally, the advantages of energy saving and reducing chemical usage were implemented throughout the dyeing process.

The effect of laser engraving on aluminum foil-laminated denim fabric

In this paper, a developed textile design method combining laser engraving and foil lamination was explored. With the foil laminating, the surface of denim fabric shows shinning effect. After that, the foil-laminated denim samples were treated with laser engraving by adjusting the parameters, including resolution (dots per inch, dpi) at 20, 30, 40 and 50 dpi and the pixel time (microsecond, μs) at 120 and 180 μs to melt and evaporate the aluminum foil and some surface fibers. The properties of the laser-engraved foil-laminated denim fabric, including weight, tearing strength, air resistance, surface observation, color appearance, colorfastness and abrasion resistance, and some low-stress mechanical properties, were investigated. The experimental results revealed that the changes in these properties are mainly related to the melted and evaporated surface laminated aluminum foil and different sizes of cracks, wrinkles and pores formed on the fiber surface with the increment of laser energy applied. This study also revealed the potential of pattern creation with different values and reflective appearance for the embellishment of denim fabric combining the aluminum foil laminating method through the laser engraving process. With lower resolutions, engraved vague patterns with small laser beam dots can be achieved. While the treatment resolution increased, clear patterns could be performed. Based on the same resolution, the higher pixel time can export more energy, which makes the pattern look more clearly. This design approach opens up new possibilities for metallic denim fabric design without any chemicals used.

Adhesion and durability of Cu film on polyester fabric prepared by finishing treatment with polyester-polyurethane and aqueous acrylate

To improve adhesion and wear durability at the interface between copper (Cu) film and polyester fabric, the Cu-coated polyester fabric was treated by two commercial solutions of polyester-polyurethane (PP) and aqueous acrylate (AC) as finishing process respectively. Both finishing agents with 5 %, 10 %, 15 %, 20 %, 25 %, 30 %, 35 % and 40 % concentrations were coated on the Cu-coated fabrics by a padding method in this study. The surface morphologies of the coated polyester fabric before and after finishing were characterized by scanning electron microscopy (SEM). The adhesion of Cu-coated film before and after the finishing treatments was measured with scotch tape method; the durability was evaluated by colorfastness to washing, crocking and perspiration. Additionally, Ultraviolet (UV) shielding, water repellency and CIE L*a*b of the Cu-coated polyester fabric before and after the finishing treatments were determined. The Cu-coated polyester fabric has a high adhesion property of the 5 level, colorfastness to washing, wet crocking and perspiration of the Cu-coated fabric were obviously enhanced to level 5, level 4-5 and level 3-4. Meanwhile, The Cu-coated polyester fabric kept an excellent UV protection with UPF value over 68 after finishing treatment with PP and AC. The results demonstrate the finishing treatment with the PP presented effectively in durability performance than the AC for the Cu-coated polyester fabric.