Advanced Materials Research Vols. 335-336

Abstract: 1,4-butylene bi-p-hydroxybenzoate (BBHB) was synthesized using methyl p-hydroxyl- benzoate and 1,4-butanediol under catalyst and stabilizer conditions; Then, the thermotropic main- chain liquid crystalline polysiloxanes (MCLCPs) with flexible spacer, were synthesized using BBHB and dimethyldiethoxysilane reagents by melting polycondensation. The chemical structures and properties were characterized by FT-IR, polarized optical microscopy (POM) and differential scanning calorimeter (DSC) respectively. It was found that MCLCPs was the type of smectic A liquid crystal, and the liquid crystal temperature ranged from 58°C to 143°C, i.e. its variationrange reached 85°C. In addition, the polysiloxane was used as the flexible main-chain and the flexible chains CH₂ was embedded into the rigid structural blocks of liquid crystalline polymers, which not only decreased the melting point below the thermal decomposition temperature, but also made the clearing point and a stable liquid crystal state observed.

Abstract: In this article, the morphologies of membranes formed by three different systems, i.e. favorable diluent/unfavorable diluent/PVDF system, water-soluble solvent/ unfavorable diluent/PVDF system, and favorable diluent/unfavorable diluent/water-soluble polymer/PVDF system, were characterized, and the relationship between porous membrane morphology and the components of favorable diluent/unfavorable diluent and water-soluble solvent/unfavorable diluent in the system was investigated. The transformation from mesopores to bicontinuous porous structures, from finger-shaped pores to bicontinuous porous structures was realized, and meanwhile PVDF microporous membranes with microfiber-shaped porous structures were manufactured.

Abstract: Polymerizable C₉ fraction was cut by atmospheric distillation of raw C₉ fraction from thermal cracking. The obtained fraction polymerized using boron trifluoride ethyl ether as catalyst and then the polymerized mixture was washed by warm 10%wt Na₂CO₃ aqueous solution and distilled water and separated by vacuum distillation for producing light colored C9 petroleum resins with high softening point. The suitable conditions for polymerization process, washing process, vacuum distillation process were investigated to improve the C₉ petroleum resins production. Under these conditions, the petroleum resins product with Gardner color index of 4-5 and softening point of 102-120°C could be obtained.

Abstract: The application of water in water cationic polyacylamide emulsion (CPAM) was studied used in bleached soda reed pulp. The main effects, such as adding amount of CPAM, the dosage of sulfate aluminium, pH value of the bleached soda reed pulp, reaction time after adding the CPAM and the concentration of the electrolyte were discussed here in detailed. The optimal application conditions of CPAM in bleached soda reed pulp were finally gained-CPAM 0.04% relative to dry fiber, 2 minutes for reaction, whip velocity 200r/min, sulfate aluminium 3%relative to dry fiber, pH value 4.0 and sodium chloride 0 relative to dry fiber.

Abstract: The as-spun fibers, which be produced by dry spinning technique, were treated with methanol solution. The results showed that the morphology, structure and mechanical properties of the as-spun fibers had changed. Before methanol treatment,the as-spun fiber had a smooth surface, after methanol treatment, the fiber exhibited rough surface and banded features along the fiber axis. The structure of the as-spun fibers changed from random-coil or silk I conformation to silk II conformation and the breaking intensity of the as-spun fibers were improved after methanol treatment. Compared with degummed silk fibers, the fibers treated with methanol had higher module, but the breaking elongation was lower, the fibers were still brittle.

Abstract: The function of the simulation sweating device when done the experiment of dynamic moisture transfer based on Munsell color index was needed to simulate the state of the human body sweating as far as possible, the performance of the simulation skin would directly affect the stability of experimental results. This paper by selecting the four kinds of materials as an alternative of the simulation skin had carried out the experiment of dynamic moisture transfer based on Munsell color index and had done the analysis of variance of experimental results, and had found that results were significantly different when using different simulation skins. Further had done the test of the preserving water rate of seven representative materials, test results show that: the 2 # simulated skin 95% cotton knitted +fabric 5% op had the best preserving water performance, the 2 # simulated skin 95% cotton knitted +fabric 5% op could been chosen as the outer layer of simulated skin .the 6 #, faux suede had better similarity with morphology of human skin tissue. So, it could be chosen as in the layer of the simulated skin.

Abstract: In this paper, PA 66 were solution blended with poly(vinyl pyrrolidone)(PVP), an amorphous polar polyamide. The thermal behaviors and morphology in the blends of polyamides (PA66)) and PVP were investigated by WAXD, DSC, FT-IR and POM methods. The equilibrium melting temperatures for PA 66 in the blends were estimated based on the linear and non-linear Hoffman-Weeks (LHW and NLHW) extrapolative methods. The interaction mode between PVP and PA66 was investigated by FT-IR spectroscopy.

Abstract: This research presents the development of the surface roughness prediction in the turning process of the plain carbon steel with the coated carbide tool by using the response surface analysis with the Box-Behnken design. The effects of cutting parameters on the cutting force and the cutting temperature are investigated. The cutting force and the cutting temperature are measured to help analyze the relation between the surface roughness and the cutting conditions. The models of cutting force ratio and the cutting temperature are also proposed based on the experimental data. The surface plots are constructed to determine the optimum cutting condition referring to the minimum surface roughness.

Abstract: A new polypyrrole derivative 4-(1H-pyrrol-1-yl) phenyl 4-(1H-pyrrol-1-yl) butanoate (NPB) was synthesized by chemical method and characterized by 1H and 13C NMR spectroscopy. A new copolymer based on NPB and 3,4-ethylenedioxythiophene(EDOT) was electrochemically synthesized. Cyclic voltammogram and spectroelectrochemical characterization showed that the copolymer film had a well-defined reversible redox process as well as electrochromic behavior. Moreover, the copolymer film exhibited a multicolor electrochromism at different potentials, fast switching time of 0.8 s at 365 nm and an optical contrast of 17% at 1100nm.

Abstract: Magnetite (Fe₃O₄) nanobranches were synthesized using an improved solvothermal technique in mixed ethanol and water solvent. Structural and magnetic properties were systematically investigated. X-ray diffraction results showed that the sample was single-phase spinel structure. The results of scanning electronic microscopy exhibited that the grains were regular like-branch with sizes from 3 to 6 μm in length and in diameter between 50 and 200 nm. The composition determined by energy dispersive spectroscopy was very close to the stoichiometry of Fe₃O₄. The saturation magnetizations (Ms) at 10 and 300 K of the synthesized Fe₃O₄ nanobranches were much lower than the theoretical values. On one hand, it could be explained by obstructive magnetizing along their non-easy magnetic axes by the shape anisotropy of Fe₃O₄ nanobranches, on the other hand, lesser Ms can also be understood by the existence of antisite defects.