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The AgI/2D-La2Ti2O7 hybrids were obtained via a facile method at room temperature. Rhodamine B, as an organic dye, was used to determine the photocatalytic activity of the samples. The photocatalytic degradation mechanism was also analyzed. Experimental results display that AgI can broaden the light absorption of La2Ti2O7 under the visible light irradiation. The photocatalytic degradation efficiency of the as-synthesized hybrids appears the tendency of first increasing and then decreasing with increasing the usage of La2Ti2O7. When the usage of La2Ti2O7 is 10%, within 60 min, the as-synthesized hybrids possess the maximum of 93.1%. This is higher than 2.1% of La2Ti2O7 and 80.9% of AgI. Moreover, the improved photocatalytic activity can be attributed to AgI particles conjugating with 2D-La2Ti2O7 nanosheets via chemical-bonds, which can enhance the separation and transformation of the photo-generated holes and electrons. In addition, the dominating role is superoxide radicals during the photocatalytic process.

In this work, a ternary magnetic composite of Fe3O4@TiO2/SiO2 aerogel with good photocatalytic activity was prepared successfully by combining sol–gel and simple hydrothermal methods with Fe3O4@TiO2 core–shell microspheres and SiO2 aerogels from industrial fly ash as starting materials. The structural and magnetic features of the as-obtained Fe3O4@TiO2/SiO2 aerogel composite were investigated by powder X-ray diffraction (XRD), Fourier transform infrared spectra (FT-IR), transmission electron microscopy (TEM), N2 adsorption–desorption measurements, UV–vis diffuse reflectance spectra (UV–vis/DRS) and vibrating sample magnetometry (VSM). The results showed that Fe3O4@TiO2 core–shell microspheres were dispersed on the surface of SiO2 aerogels. The Fe3O4@TiO2/SiO2 aerogel composite material possessed excellent magnetic properties at room temperature, high adsorption capacity to organic pollutants, enhanced charge separation efficiency and strong light absorption in the visible region. The photocatalytic activity of the prepared Fe3O4@TiO2/SiO2 aerogel for Rhodamine B degradation under visible light irradiation was systematically investigated by varying the operational parameters such as pH value, catalyst concentration, irradiation time, and initial substrate concentration, etc. The photocatalytic reactions obeyed pseudo-first-order kinetics according to Langmuir–Hinshelwood model. The repeatability of photocatalytic activity was also tested. Compared to pure TiO2 and Fe3O4@TiO2 core–shell microspheres, the ternary composite of Fe3O4@TiO2/SiO2 aerogel showed higher photocatalytic activity for Rhodamine B degradation, which meant that this material can serve as an efficient and recyclable multifunctional photocatalyst for the degradation of hazardous organic dyes in wastewater.

A low carbon bainitic steel YP960 for construction machinery was designed by directly quenching and tempering (DQ&T), and the mechanism for tempering temperature on tensile behavior was studied. A modified Voce relation was established using the experimental results to describe the stress–strain relationship of the as-quenched and as-tempered specimens, and quantitative model parameters for flow curve have been derived and discussed taking account into the evolution of precipitations and dislocation cell during temper. The reliability of the model was verified by a comparison between the predicted flow stress curves from the model and the experimental data. When tempering temperature is 823 K, the “hard regions” and “soft regions” form as a result of inhomogeneous recovery. With the help of Crussard–Jaoul (C–J) analysis, the cooperative deformation relationship between softer regions and harder regions was studied, which was confirmed by EBSD and TEM analysis. The cooperative deformation between softer regions and harder regions can reduce stress concentration and improve the uniform elongation of low carbon bainitic YP960 steels.

The oxidative stability of castor oil based biodiesel, added different antioxidant, was studied systematacially through pressure differential scanning calorimetry (PDSC), accelerated oxidation test, constant temperature method, programmed temperature method. The result shows after adding antioxidant in castor oil, the generation of hyperoxide and acid value were suffocated for the biodiesel. When the content of antioxidant 300 was 0.6 wt.%, the initiation oxide temperature raised to 197.7°C, the acid value reduced to 1.41, the solubility of oxide reduced to 1.40mg/100mL, and the activity energy of oxidation was 48.18kJ/mol.

Linear polyvinyl alcohol ( PVA ) as the matrix, Glutaraldehyde as crosslinking agent, the crosslinked polyvinyl alcohol microspheres ( CPVA ) was prepared by inverse microemulsion polymerization. Influence factors for forms and particle size of crosslinking spheres such as the ratio of oil and water, reaction temperature and time, crosslinking agent and catalyst use level, stirring speed. When reaction conditions changed, the particle size would change accordingly.

Material transfer characteristics and surface morphology of contact material reflects their electrical erosion performance. In this paper, by using a JF04C contact material testing machine, the characteristics of electrical erosion of PtIr contact materials are acquired under low voltage, resistive load and small current. By means of an electronic balance and SEM, the material transfer values of the PtIr contact materials and the characteristics of contact material surface profile are obtained and analyzed. The results show that PtIr alloy contact materials mainly transfer from cathode to anode and its breaking arcs are metallic phase.

By the in situ compatibilization, PP/POE blends were prepared with dicumyl peroxide (DCP) as initiator, Trimethylolpropane triacrylate (TMPTA) as co-during systems and the metallocene polyolef in elastomers ploy (ethylene-1-octene) (POE) as toughening rubber. The effects of additive amount for TMPTA、POE on the mechanical properties were studied. The results showed that the maximum value of the room-temperature and low-temperature impact strength for the composite was reached to 52.03KJ/m2 and 37.29KJ/m2, and the elongationfor was reached to 482.74%.

The surface properties of polymer membranes are very important to their separation performance. It is generally accepted that a hydrophilic membrane surface is favorable for applications in water treatment and bioseparation, because the hydrophilic surface can enhance water permeate flux and mitigate membrane fouling. Microporous polypropylene membrane (MPPM) is a promising membrane material for membrane distillation and membrane gas–liquid contactor, due to the intrinsically high hydrophobicity of polypropylene. However, it is the hydrophobicity that severely limits the wider application of MPPM in aqueous solutions and biomedical fields. Surface hydrophilization is, therefore, logically necessary. Surface engineering of polymer membranes encompasses those processes which modify the membrane surfaces to confer different properties to those of the bulk and thus improve their in-service performance. This review provides a concise summary and discussion of the surface engineering strategies developed in our...

The Ag2SO3/NaNbO3 hybrids have been fabricated via a facile method at room temperature. Several methods such as X-ray diffraction, UV-Vis diffuse reflectance spectroscopy, scanning electron microscopy, electrochemical impedance spectroscopy and X-ray photoelectron spectroscopy were used to characterize the samples. Moreover, the photocatalytic activity of the samples was assessed by degradation of rhodamine B and methyl orange under the visible light illumination. Experimental results indicated the photocatalytic degradation efficiency of the as-fabricated hybrids was first increased and then decreased with increasing the dosage of NaNbO3. When the molar ratio of Ag2SO3 to NaNbO3 was 1:0.7, the as-fabricated composites had the best photodegradation efficiency of 96.4% in 30 min for rhodamine B and 97.1% in 60[Formula: see text]min for methyl orange, respectively. These were obviously higher than that of pure samples. Furthermore, Ag2SO3 was conjugated with NaNbO3 via chemical-bonds rather than physical contact. In addition, the possible photocatalytic degradation mechanism was also provided and the main roles during the process of photocatalytic degradation were played by holes.

Wettability of a solid surface is highly important to its practical application, especially for the surface that shows thermo-responsive properties. In this paper, we describe a thermo-responsive stick-slip behavior of water droplets on the surfaces of poly(N-isopropylacrylamide) (PNIPAM)-grafted polypropylene membranes. Field emission scanning electron microscope (FESEM) images elucidate that the morphology of PNIPAM-grafted membrane surface is thermo-responsive, i.e., the surface becomes rougher above the lower critical solution temperature (LCST) of PNIPAM. On the surface of nascent polypropylene membranes, the water droplet shows a smooth motion resulting in advancing and receding water contact angles of 111° and ∼65°, respectively. On the PNIPAM-grafted membrane surfaces, the water droplet shows a stick-slip pattern above the LCST, whereas it advances smoothly below the LCST. This phenomenon is reproducible and can be ascribed to the energy barriers enhanced by the shrink of PNIPAM chains above the LCST. We also find that the slip contact angle decreases from 102° to 92° after several stick-slip cycles. This decrease is attributed to the water adsorption on the grafted PNIPAM layer, which is confirmed by the continuous decrease of the receding water contact angle.

To endow microporous polypropylene membrane (MPPM) with durable surface hydrophilicity, a facile interfacial crosslinking approach was developed, combined with a pretreatment by dielectric barrier discharge (DBD) plasma at atmospheric pressure. The commercially available polyethylenimine (PEI) was coated on MPPM firstly and was sequentially crosslinked with p-xylylene dichloride and quaternized with iodomethane to form a permanently positively charged layer. The physical and chemical changes of the membrane surface were characterized by tensile test, FT-IR/ATR, XPS, and FESEM. The surface hydrophilicity of the modified MPPMs was evaluated by water contact angle and pure water flux measurements. Besides, the influence of surface charge on protein filtration involving flux decline and protein transmission was also investigated in detail. It is found that the optimal time of DBD plasma treatment is ∼30 s. Mass gain for the MPPMs during the interfacial crosslinking can be controlled conveniently by adjusting the PEI concentration from 1.0 to 15 g/L. The surface hydrophilicity can be significantly enhanced and is durable, characterized by the sharp decrease of water contact angle, the double increase of pure water flux and the stability test. The results of protein filtration suggest that the obtained highly hydrophilic and charged membrane surface is resistant to protein fouling. Furthermore, almost 100% of protein transmission indicates that the microfiltration characteristic of MPPMs is unchanged.

In this paper, we describe a thermo-responsive membrane based on microporous polypropylene membrane (MPPM). Comb-like poly(N-isopropylacrylamide) (PNIPAM) was grafted onto the MPPM surface using surface-initiated atom transfer radical polymerization (ATRP). Hydroxyl groups were firstly introduced onto the membrane surface by the ultraviolet-induced graft polymerization of 2-hydroxyethyl methacrylate. Then ATRP initiators were immobilized through the reaction between the tethered hydroxyl groups and 2-bromoisobutyryl bromide, which initiated the ATRP of NIPAM on the membrane surface. Attenuated total reflectance Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and field emission scanning electron microscopy were used to characterize the chemical composition and surface morphologies of the modified membranes. The thermo-response of the modified membranes was evaluated by water contact angle and water permeation measurements. It is found that both water contact angles and water fluxes have obvious response to the environmental temperature. This type of membrane with controlled PNIPAM graft layer can be applied in many fields including smart separation.

A hydrophilic surface is very important for hydrophobic separation membranes such as polypropylene microporous membranes (PPMMs). In this work a facile and effective method, interfacial crosslinking combined with pretreatment by dielectric barrier discharge plasma at atmospheric pressure, was developed for endowing PPMMs with a hydrophilic and charged surface. Poly( N , N -dimethylaminoethyl methacrylate) (PDMAEMA) and p -xylylene dichloride were selected for quaternization crosslinking to form a positively charged coating layer, which was characterized with FT-IR/ATR, XPS, and FESEM. Water contact angle and pure water flux measurements were conducted to evaluate the surface hydrophilicity. The influence of surface charges on protein filtration was also investigated. It is found that the mass gain of interfacial crosslinking increases almost linearly with increasing the PDMAEMA concentration from 0.5 to 10 g/L. The crosslinking degree is larger than 80% according to the XPS results, ensuring the stability of the crosslinking layer. The surface hydrophilicity is demonstrated by the sharp decrease of water contact angle from 145° to 20°. The pure water flux also increases 3 times under the optimized conditions. Furthermore, the results of protein filtration suggest that these highly hydrophilic and charged surfaces can effectively resist the fouling of proteins.

A new copolyamide, nylon 6/66/11, used for hot-melt adhesives, was prepared by hydrolytic polymerization and melt polycondensation. Intrinsic viscosity, melting point, glass transition temperature, cold crystallization, thermogravimetry (TG) and adhesion strength of the resultant hot-melt adhesives were investigated. DSC thermograms of the copolyamide showed that both the melting point and glass transition (T g) temperatures decreased as the molar fraction of aminoundecanoic acid increased. The T g practically did not change as the mole fraction of aminoundecanoic acid increased from 60% to 80%, but cold crystallinity of the copolyamide decreased. The thermal gravimetric analysis indicated that the resultant copolyamide had a high thermal stability. The copolyamide had the best combination of properties when the molar fraction of aminoundecanoic acid was about 65%.

The surface properties of polymer membranes are crucial to their separation performances. For the microporous polypropylene membranes, the high hydrophobicity and lack of functionality easily cause protein adsorption and subsequent microorganism attachment and biofilm formation, i.e. biofouling. Thus, their applications in water treatment, bioseparation and biomedical fields are largely limited. Surface hydrophilisation and antibacterial functionalisation are, therefore, reasonably necessary. This review provides a concise summarisation of related studies according to the surface modification strategies. Especially, the interfacial crosslinking approach developed in our previous studies is presented in detail.