Advanced Materials Research Vols. 391-392

Abstract: With synthetic wastewater, a comparative study on co-sorption of Zn(II) and As(V) by Fe/Al-PILCs prepared at different calcination temperatures was investigated using a lab-scale batch experiment technique. The effects of relevant parameters, such as pH value of solution, adsorbent dosage and contact time were examined, respectively. The results show that sorption efficiencies of Zn(II) and As(V) by Fe/Al-PILC prepared at calcination temperatures of 300 °C are higher than those at 350 and 400 °C and the higher calcination temperature is, the lower sorption efficiencies of Zn(II) and As(V) are. Co-sorption isotherm data of Zn(II) and As(V) by Fe/Al-PILCs were fitted well to Langmuir isotherm and the maximum sorption capacities of Zn(II) and As(V) on Fe/Al-PILC (Q₀) prepared at 300 °C are 13.95 and 15.87 mg/g, respectively, which are higher than those at calcination temperatures of 350 °C and 400 °C. The maximum sorption capacity of As(V) decreases more obviously with increasing calcination temperature than Zn(II) does. n>1 from Freundlich isotherm indicate that the sorption of Zn(II) and As(V) by Fe/Al-PILCs is favorable. E values from D-R model indicate that the type of sorption of Zn(II) and As(V) by Fe/Al-PILCs is physical. There is significant potential for Fe/Al-PILC prepared at calcination temperature of 300 °C as an adsorbent material for Zn(II) and As(V) removal from aqueous solutions.

Abstract: SnO₂ has been widely used in the industry, and is important materials in the fields of electron, ceramics and chemistry. SnCl₄ was employed as raw material, acrylamide and N,N’-methylenediacrylamide were used as monomer and lattice reagent, respectively. In present work, SnO₂ nano-sized powder was prepared by the polymer-network method. The precursor was characterized using DTA-TG. The phase structure and particle size of the powder was determined by XRD and TEM, respectively. The results indicated that the SnO₂ powder with particle diameter size smaller than 50nm was obtained when the ratio of monomer and lattice reagent was 5:1, and the sintering temperature was 500 °C. Moreover, the distribution of powder particles was uniform and the specific surface area was big.

Abstract: In this paper, the structure evolution of Fe-7.5at.%Ni thin strips under near-rapid solidification conditions was investigated. One-dimensional (1D) heat transfer model was used to calculate the cooling rate of thin strips. The calculated results showed that the decrease of distance from the surface, made the effective heat transfer increase sharply, which led to a higher cooling rate. Moreover, the experimental results showed that the size of the columnar crystals increased clearly by the increase of the distance from the surface, and equiaxed grains appeared when the distance was above 0.75mm. In addition, it is indicated that even the strip thickness changed from 1.0mm to 2.0mm, the size of columnar crystals didn’t change much in regions which have the same distance from the surface.

Abstract: The performances of CTP plate depend heavily on polymer binder and those capable of producing large image contrast by exposure are keys to quality plate. This research proposed a polymer resin containing hydrophilic spices in the side chain which could be sheltered by the thermal induced crosslinking reaction during plate manufacturing process and released upon imaging exposure. The resin was prepared through esterification reaction of maleic anhydride with phenolic resin, and its chemical structure was characterized by IR spectrum. Plate coatings were formulated with the modified polymer as binder resin, 2,2-bis(4- (2-(vinyloxy)ethoxy)phenyl)propane as the crosslinking agent, a near infrared absorbing dye and crystal violet as the tracing agent. Solubility of the exposed and unexposed coatings in diluted aqueous alkaline was investigated in situ using a home-made dissolving rate tester. It was found that polymer containing 4-6% mole carboxyl groups led to high image contrast and this contribution came directly from the cross-linking and decrosslinking reactions. Preliminary test indicated that this polymer coating generated positive image of high contrast after exposure and could be used as CTP plate coating for thermal laser imaging.

Abstract: Previous research indicated that the expansion property of MgO-type expansive agent (MEA) strongly depended on the amount. However, the quantitative effect of amount on expansion property of MEA has not been clearly demonstrated. In the present the expansion value of cement paste with 3%, 4%, 5% and 6% MEA calcinated at 850°C and 1200 °C, and then relative expansion value was introduced to investigated the relationship between the mount and expansion of MEA. The results indicated The relative expansion of MEA calcinated at 850°C was relative invariant to curing temperature and proportional increased with the amount ratio. The relative expansion of MEA calcinated at 1200°C proportional increased with curing age, and the increasing rate rose with the amount ratio of MEA and curing temperature.

Abstract: The epoxy resin based repairing material(REM) is suitable for repairing cracks and holes in concrete or broken concrete due to its high bond strength and high durability. The compressive strength and flexile strength are 76.4MPa and ＞12.5MPa at 28d, and the retest strength still remain 73.4MPa and ＞12.5MPa respectively. The fracture location of cement mortar specimen bonded by RME is at cement mortar, that is, the bond strength between REM and cement mortar is more than mortar itself. The compressive strength of RME keeps 93.3% under ultraviolet light radiation (Peak Value 308nm, 49.5 W/m²) for 1700h.

Abstract: Previous research indicated epoxy resin based repairing materials have been widely used due to its outstanding advantages in strength, durability corrosion, abrasion resistance and reasonable price, etc. But its nonperforming resistance of ultraviolet radiation restricted popularization and using. In this paper the effect of inorganic fillers (quartz sand, rutile type titanium dioxide and talc powder) and organic fillers (HALS-770 and UV-P) on the Compressive strength of RME irradiated was studied. The results indicated that inorganic and organic fillers revealed good shielding effect. The inorganic fillers decreased the compressive strength of RME about 20MPa, and talc powder was better than quartz sand and rutile type titanium dioxide. Organic fillers had unaffected in strength, and combined use of HALS-770 and UV-P had better resistance than alone. The strength retention of RME with talc powder and combined with HALS-770 and UV-P irradiated 4500h were 85.65% and 93.5%.

Abstract: Organosilicone paints were prepared by mixing as-synthesized silicone resin, pigments, fillers and other additives. Through scraping and baking, the thick film coating on the treated aluminum alloy was obtained. The optimum range of P/B (weight ratio of the pigment/binder) was determined to be 0.75:1 by investigating the influence of the P/B on the liquidity and thickness of the coating, indicating that the thickness of the coating reached 500μm. When mica powder, talc powder, nanometer titanium dioxide, sub-micron titanium dioxide, sphere silicon fine powder and lipophilic silica content were 15 wt%, 15wt%, 15wt%, 10wt%, 20wt% and 3 wt % of solid mass of silicone resin, respectively, the coating had good gloss and no holes were occurred on the surface. And there were no bubbles or shrinkage cavities in the obtained coating when the leveling agent S43, defoamer 900 and dispersant 670 content were 0.7 wt%, 0.1wt% and 0.3wt% of the total mass of paint, respectively.

Abstract: The exploitation and application of thermal conductive polypropylene composites were introduced in the article. Meanwhile, the development of filled and grafted polypropylene composites occurring both at home and abroad were discussed in detail. The thermal conductive mechanism of the polymer composites were summarized. At last，the approaches of improving the thermal conductivity of polypropylene materials were also raised.

Abstract: Novel poly(aryl ether quinoxaline)s (PEQs) were prepared via a two-step procedure. First, poly (ether benzil) (PEB) was synthesized by the polycondensation of 4,4’-difluorobenzil and 4,4’-isopropylidenediphenol.Then, PEB was reacted with 1,2-diaminobenzene and 4,4'-oxydibenzene-1,2-diamine to give the PEQs. The molecular weight of the PEQs could be adjusted easily by varying the molar ratio of 1,2-diaminobenzene to 4,4'-oxydibenzene-1,2-diamine. The PEQs exhibited good solubility in common organic solvents such as NMP, DMAc, DMF, cyclohexanone and chloroform. In addition, the PEQs also had high glass transition (T_g) temperatures and good thermal properties, with an initial thermal decomposition temperature above 475 oC and glass transition temperatures above 210 oC. They also exhibited excellent resistance to strong acid and alkali.