PA6/MPEG共混物的制备及性能研究

利用聚乙二醇(PEG)的端羟基与马来酸酐(MAH)进行化学反应，制备了聚乙二醇双马来酸酯(MPEG)。通过熔融共混的方法在PA6中混入质量分数为2％-10％的MPEG，制得PA6／MPEG共混物。MPEG的加入可起到增塑作用。随其加入量的增加，共混物的拉伸强度和洛氏硬度降低，缺口冲击强度增大，同时共混物的亲水性明显提高。     

Polyvinylidene fluoride ultrafiltration membrane blended with nano-ZnO particle for photo-catalysis self-cleaning

A novel photo-catalysis polyvinylidene fluoride ultrafiltration membrane was successfully fabricated via phase inversion method. The membrane matrix was supplemented with nano-ZnO of different content for membrane modification. Filtration experiments, contact angle measurements, scanning electron microscope/energy dispersive X-ray spectrometer analysis, and mechanical tests were conducted to characterize the modified membranes. The photo-catalysis tests clearly showed that the modified PVDF membranes had significant photo-catalysis self-cleaning capability. PVDF-1 (adding 1.0% nano-ZnO with PVDF) membranes achieved 94.8% water flux recovery after exposure to low-pressure 10 W UV-C mercury lamp irradiation for 30 min, whereas the raw membrane only reached 63.3% recovery. The implantation of nano-ZnO on the inner surface of the membrane (i.e., the pore wall) may have been responsible for the enhancement of the photo-catalysis self-cleaning property. The pure water flux of the PVDF-1.5 (adding 1.5% nano-ZnO with PVDF) membrane was nearly five times as great as that of pure PVDF. Supplementation of nano-ZnO could improve the mechanical properties of the membrane, but excessive supplementation of nano-ZnO could cause a decline in the membrane mechanical properties.     

预辐射接枝丙烯酰胺改性PVDF粉体及其亲水性滤膜的制备

通过γ射线预辐射接枝方法将丙烯酰胺(Acryl amide,AAm)单体接枝到聚偏氟乙烯Poly(vinylidene fluoride),PVDF]粉体上,通过测定粉体接枝前后氟元素含量的变化来计算接枝率.研究了同一单体浓度下,接枝率随反应时间的变化规律,并将具有不同接枝率的改性粉体溶解在N-甲基吡咯烷酮(N-met...     

Particles from bird feather: A novel application of an ionic liquid and waste resource

The dissolution and regeneration of the waste chicken feathers in an ionic liquid of 1-butyl-3-methylimi-dazolium chloride ([BMIM]Cl) were demonstrated for preparing chicken feather based particles. The structure and properties of the regenerated chicken feathers were investigated by FT-IR, XRD, SEM, BET and water contact angle. The crystallinity of the regenerated chicken feathers was decreased, and the content of β-sheet was 31.71%, which was clearly lower than the raw feather (47.19%). The surface property of chicken feather changed from hydrophobicity to hydrophilicity after regenerated from [BMIM]Cl as indicated by the change of the water contact angle from 138 to 76°. The chicken feather particles regenerated from [BMIM]Cl showed an excellent efficiency (63.5–87.7%) for removing Cr(VI) ions in wastewater at the concentrations from 2 to 80 ppm. The Freundlich constant (k_F) for the adsorption of Cr(VI) ion by the particles of the regenerated chicken feather was four times larger than that of the raw chicken feather, the possible reason is the hydrophilic groups such as amino and carboxyl groups were tend to self-assemble towards surface when the dissolved CF were regenerated by water, amino group will partly hydrate to cationic amino and Cr(VI) ion occurs as an anion in the aqueous phase, so the cationic amino will adsorb the anionic Cr(VI) ion onto the RCF particles through electrostatic attraction. This work demonstrated a new application of the ionic liquid for dissolving chicken feather and a renewable application of waste chicken feather for removing Cr(VI) ion in water.     

Oxygen plasma induced hydrophilicity of TiO2 thin films

Anatase nano-TiO₂ thin films were fabricated by reactive magnetron sputtering metal Ti target followed by thermal annealing in air at 450 °C for 2 hrs. The crystalline structure of the sample films were characterized by X-ray diffraction (XRD) and the hydrophilicity was characterized with the diameters of 1 μl water drop. The films were irradiated by oxygen plasmas and the effects of the radio frequency (rf) power, the gas pressure and the irradiation time of the oxygen plasmas on the hydrophilicity of the TiO₂ thin films were investigated. Hydrophilicity can be induced by oxygen plasmas and further more the hydrophilicity shows high stability whenever under the natural light or in dark.     

Improvement in poly(lactic acid) fabric performance via hydrophilic coating

The effects of a hydrophilic coating on poly(lactic acid) (PLA) fabric using polyethylene glycol-dimethyloldihydroxyethyleneurea (PEG-DMDHEU) were studied to obtain highly cross-linked polyethylene glycol (PEG) with acceptable fastness properties owing to the possibility of fixation PEG on the fibres surface at lower temperature than melting point of PLA fibres. PEG as a Phase Change Materials (PCMs) imparts thermal adaptability, which is so important for the comfort of textiles, to the substrate. While there is a good adhesion between the fibre and the PEG polymer for cotton and polyester fibres, polymer adhesion to PLA fibres and its effects on PLA fabrics have never been studied. The effect of hydrophilic coating on the PLA fabric was studied in comparison to polyethylene terephthalate (PET) fabric by measuring the thermal regulating effect, antistatic, air permeability, and mechanical properties. The results exhibit the possibility of multipurpose finishing on both fabrics samples leading to permanent thermal regulating effect and durable antistatic finish.     

Carbon nanotube blended polyethersulfone membranes for fouling control in water treatment

Multi-walled carbon nanotube/polyethersulfone (C/P) blend membranes were synthesized via the phase inversion method. The resultant membranes were then characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and contact angle. The C/P blend membranes appeared to be more hydrophilic, with a higher pure water flux than the polyethersulfone (PES) membranes. It was also found that the amount of multi-walled carbon nanotubes (MWCNTs) in the blend membranes was an important factor affecting the morphology and permeation properties of the membranes. After 24 h of surface water filtration with 7 mgC/L TOC content, the C/P blend membranes displayed a higher flux and slower fouling rate than the PES membranes. Subsequent analyses of the desorbed foulants showed that the amount of foulant on bare PES membranes was 63% higher than the C/P blend membrane for 2% MWCNTs content. Thus, the carbon nanotube content of the C/P membranes was shown to alleviate the membrane fouling caused by natural water.     

吸湿快干功能纯粘胶纱的设计开发

为了改善粘胶、棉等吸湿性纤维的吸湿快干、湿热舒适性能,利用混纺纱横截面的分层结构理论,采用不同细度粘胶纤维混纺,设计开发了一种外层疏水而内层亲水的新型结构纯粘胶纱。采用3.3 dtex粘胶纤维与预先进行疏水整理的5.5 dtex粘胶纤维纺制70/30 35.7 tex、50/50 35.5 tex纱,测试分析了成纱结构、纤维与纱线的吸湿放湿性能、织物的透湿性。结果表明,经疏水整理的较粗粘胶纤维分布在纱的外层,较细粘胶纤维分布在纱的内层,形成皮芯结构;经过疏水整理后纤维的吸湿回潮能力有所降低,但初始回潮速率几乎相同,纤维吸湿后的干燥速度明显增强;成纱中粗纤维含量增多,吸湿初始速率增加,但接近平衡时吸湿能力趋于一致,成纱的放湿速率增强;含有疏水处理粗纤维的织物透湿量增加,并且随着疏水处理粗纤维含量的增加织物透湿性增强。     

Enhanced mechanical properties and hydrophilic behavior of magnesium oxide added hydroxyapatite nanocomposite: A bone substitute material for load bearing applications

Hydroxyapatite is a multifunctional biomaterial that combines biocompatibility and bioactivity for various biomedical applications such as bone repairing and bioimaging. In the present study nano-hydroxyapatite (n-HAp) was synthesized using microwave irradiation technique. Subsequently, the MgO was introduced into the n-HAp matrix and various bioactive compositions of HAp-MgO nanocomposites were fabricated. The structural, mechanical, in vivo cell viability, and in vivo imaging properties of these nanocomposites were studied. The XRD results show that the composites sintered at 1200 °C, n-HAp partially decomposed into beta-tricalcium phosphate (β-TCP). The sintered density of the composites varying from 2.72 ± 0.066 to 3.03 ± 0.093 g cm⁻³ with the addition of 0.0–2.0 wt % of MgO. As increasing the amounts of MgO, a remarkable increase in the mechanical properties of the composite was achieved. The composite HAp-1.0MgO exhibited the highest mechanical properties with a compressive strength of 111.20 ± 5 MPa, fracture toughness 136.98 ± 5 MJ/m³ and revealed much amplification than pure n-HAp. Thus, the addition of MgO acting as an excellent mechanical reinforcing agent. The surface morphology of the composites revealed a significant change in the porous surface to denser. The low contact angle revealed the considerable hydrophilic nature of the composite surface. The biological study of these nano-composites with Drosophila third instar larvae indicated comparable or more favorable biocompatibility in terms of cell viability. Also internalized by Drosophila third instar larvae exhibited fluorescence under green and red filters using epifluorescence microscopy. Thus, the fabricated HAp-MgO nanocomposites with excellent biological properties are expected to be a multifunctional bioactive material for bone tissue regeneration and cell imaging applications.     

The use of a micro-cavity discharge array at atmospheric pressure to investigate the spatial modification of polymer surfaces

A micro-cavity discharge array (2500 cavities of 50 µm² size) was operated in neon at atmospheric pressure to modify polystyrene (PS), fluorinated ethylene-propylene co-polymer (FEP) and polytetrafluoroethylene (PTFE) polymer surfaces and, with the injection of a polymerisable monomer (acrylic acid), to deposit patterned, thin polymeric coatings. The aim of this study was to investigate the utility of these micro-discharge sources in the surface treatment of polymers and for the patterned deposition of polymeric material. The influence of the driving frequency, treatment time and sample-array distance on polymer surface treatment was investigated. X-ray photoelectron spectroscopy (XPS) was used to explore the surface chemistry of the treated polymer surfaces and of the polymer deposits. It was found that increasing the micro-cavity discharge source driving frequency and/or treatment time and decreasing the sample-array distance all led to a significant decrease in surface energy as determined by water contact angle measurements. For a period of time, post treatment surface hydrophilicity degraded due to the well known “ageing effect” but stabilized after two days. Finally, it was demonstrated that the device could be used for the localized, array sized, deposition of acrylic acid. High resolution XPS analysis of the deposit registered a C 1s spectra typical of poly(acrylic acid) with a prominent peak centred at approximately 289.3 eV indicating a relatively high level retention of the original monomer functionality. These results demonstrate that micro-cavity discharges, operated at or near atmospheric pressure, can be used to both modify and locally deposit polymeric material.