The room-temperature ionic liquid 1-allyl-3-methyl-imidazolium chloride [amim][CI] was synthesized. The conductivities and viscosities of [amim][CI] + water and + ethanol binary mixtures were determined in the temperature range from 293.15 K to 333.15 K, and the mole fraction of the solvents in the mixtures was in the range of 0 to 0.80 for water and 0 to 0.55 for ethanol. The conductivities of the mixtures increased with increasing concentration of the solvents and temperature in the solvent concentration range studied. The viscosities of the mixtures decreased with increasing temperature.

An electric-current-assisted method was used to mineralize dense hydrogels and create hydroxyapatite/hydrogel composites with unique hierarchical structures. The microstructure of the final material can be controlled by the mineralization technique and the chemistry of the organic matrix. A hydroxyapatite/hydrogel composite was obtained with a large inorganic content (approximately 60% of the weight of the organics). After being heated to 1050 degrees C, the sintered inorganic phase has a very uniformly distributed porosity and its Brunauer-Emmett-Teller (BET) surface area is 0.68 m(2)/g.

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With advantages such as design flexibility in modifying degradation, surface chemistry, and topography, synthetic bone–graft substitutes are increasingly demanded in orthopedic tissue engineering to meet various requirements in the growing numbers of cases of skeletal impairment worldwide. Using a combinatorial approach, we developed a series of biocompatible, hydrolytically degradable, elastomeric, bone–like biocomposites, comprising 60 wt% poly(2–hydroxyethyl methacrylate–co–methacrylic acid), poly(HEMA–co–MA), and 40 wt% bioceramic hydroxyapatite (HA). Hydrolytic degradation of the biocomposites is rendered by a degradable macromer/crosslinker, dimethacrylated poly(lactide–b–ethylene glycol–b–lactide), which first degrades to break up 3–D hydrogel networks, followed by dissolution of linear pHEMA macromolecules and bioceramic particles. Swelling and degradation were examined at Hank’s balanced salt solution at 37 °C in a 12–week period of time. The degradation is strongly modulated by altering the concentration of the co–monomer of methacrylic acid and of the macromer, and chain length/molecular weight of the macromer. 95% weight loss in mass is achieved after degradation for 12 weeks in a composition consisting of HEMA/MA/Macromer = 0/60/40, while 90% weight loss is seen after degradation only for 4 weeks in a composition composed of HEMA/MA/Macromer = 27/13/60 using a longer chain macromer. For compositions without a co–monomer, only about 14% is achieved in weight loss after 12–week degradation. These novel biomaterials offer numerous possibilities as drug delivery carriers and bone grafts particularly for low and medium load–bearing applications.

The hybrid microspheres with polystyrene core coated by titania nanoparticles were prepared by miniemulsion polymerization, and the as-prepared samples were characterized by SEM, XRD, TG-DTA, XPS, and SPS techniques. TiO2 nanoparticles experienced two processes of phase transition, i.e., amorphous to anatase and anatase to rutile at the calcining temperature range from 400 to 1000 degrees C. The phase transformation temperature of TiO2 hybrid microspheres from anatase to rutile was increased by about 300 degrees C due to the blocking function of calcined polymer remainder. SPS results present that the band-gap of hybrid microspheres is 3.2-3.4 eV, which is larger than that of pure TiO2. The maximum intensity of the SPS signal is about 3 times larger for the hybrid material as compared to the pure TiO2. In addition, the photocatalytic degradation rate of TiO2 hybrid microspheres was 15% faster than that of pure TiO2 in the experiment of the photocatalytic degradation of methyl orange.

Poly(vinyl alcohol) (PVA) hydrogels were prepared in aqueous solutions at different concentrations using glutaraldehyde (GA) as cross-linker. The gel fraction, increase rate of gels, critical gel point, and swelling ratio were measured. Furthermore, the influences of intramolecular cyclization on the cross-linking processes and the structure of formed hydrogels were studied. The results show that the degree of intramolecular cyclization and the ratio of [-CHO]/[-OH] at critical gel point (r c ) increase with the decrease of PVA concentration. The bulk gels do not form when PVA concentration is below 1.1 × 10 -2 g/mL even at higher GA/PVA mixture ratio. In the concentration range of (2.20-12.3) × 10 -2 g/mL, intramolecular cyclization fraction is basically not changed with gel fraction above the critical gel point. The way of gel growing is controlled by PVA concentration. In a certain range, the lower the PVA concentration is, the higher the increase rate of gels is. The equilibrium swelling ratio decreases with increasing PVA concentration. The structure of PVA hydrogels can be adjusted by changing the cross-linker or polymer concentrations.

Poly­(3,4-ethylenedioxythiophene)/lignosulfonate acid (PEDOT/LS) submicron particles are doped into a 3,4-ethylenedioxythiophene (EDOT)/water mixture as a solid stabilizer to form a Pickering emulsion. The conductivity of the new PEDOT/LS complexes prepared by Pickering emulsion polymerization (PEDOT/LS-PEP) is improved by 2 orders of magnitude. The structure and properties of PEDOT/LS-PEP are investigated by UV, FTIR, XRD, XPS, DLS, optical microscope, four point probe meter, and surface resistance tester. The results show that the average particle size increases from 550 nm to 2.4 μm, and the PEDOT content in PEDOT/LS-PEP is 3.5 times that in the original PEDOT/LS submicron particles, while the structure of PEDOT/LS-PEP remains amorphous. Due to the enhancement in conductivity, the coating film made by PEDOT/LS-PEP decreases the surface resistance of glass from 1012 to 106 Ω sq–1. These new PEDOT/LS-PEP complexes meet the requirement of industrial antistatic materials well.

To study the energy evolution and acoustic emission characteristics of layered sandstone under anchorage in the process of deformation and failure, the sandstone samples from Chuxiong Yi Autonomous Prefecture, Yunnan Province were selected for uniaxial compression testing. The energy evolution in the process of sandstone failure and the spatial fractal characteristics of acoustic emission events in the process of deformation and failure were investigated. Research results show that anchoring can make layered sandstone store more energy, the stored energy first increases, then decreases with the increase of bedding angle; the B value of sandstone under anchorage is generally higher than that of unanchored sandstone in the whole deformation and failure process, and the continuous decline in B value can be used to indicate a precursor to instability and failure; under the action of anchoring, the D value of sandstone (its fractal dimension) also increases, then decreases with the increase of bedding angle. The D value changes within [2, 3]. At a given bedding angle, the D value of anchored sandstone is greater than that of unanchored sandstone, the D value of 30° anchored sandstone increased the most (by 12.33%); the maximum D value occurred in 45° anchored sandstone (reaching 2.72) and the spatial distribution of acoustic emission events and damage of sandstone under anchorage is also more uniform; under increasing stress, the number of acoustic emission events is less widely distributed in the early stage and more densely distributed in the later stage. The growth rate of the D value varies across different peak stress ranges, which is more significant under the action of anchorage. The acoustic emission event counts grow evenly and slowly in the space, and the toughness of sandstone is improved to a certain extent under the action of anchorage.