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61.
丁腈羟增韧环氧树脂形态与力学性能 总被引:4,自引:0,他引:4
研究了丁腈羟增韧环氧树脂的力学性能和形态结构,丁腈羟的用量、丁腈羟中丙烯腈的含量、固化条件对所形成的微区尺寸都有较大影响,并进一步影响固化物的力学性能。 相似文献
62.
The rheological behavior and the morphology in blends of polyethylene terephthalate (PET) with ionomeric polyester were investigated over a wide range of different blending ratios. The ionomeric polyester is derived from PET modified through copolycondensation with sulfonate moiety, sodiosulfo isophthalate (Na-SIP), iso-phthalic acid (IPA) and polyethylene glycol (PEG). The results showed that the apparent viscosity and non-Newtonian index of the PET/ionomeric polyester blend system had a nonlinearity change with the change of the blend ratio of PET/ionomeric polyester. The anomaly of the viscous flow activation energy change was found as the content of ionomeric polyester was about 40% (w/w) in the blend system, suggesting the presence of physical cross-linked structure formed by strong polar tangling points and the phase separation owing to poor compatibility between the PET and ionomeric polyester. The morphology and thermal behavior of the blends were observed, respectively, with differential scanning calorimetry (DSC) and atomic force microscopy (AMF). 相似文献
63.
ZHOU Hai-cheng XU Sheng PENG Qing LI Ya-dong 《高等学校化学研究》2006,22(1):11-13
IntroductionNano-sized semiconductors are of great interestdue to their special optical and electronic proper-ties[1,2].As one of the mostimportantⅡ—Ⅵsemicon-ductors,CdS has importantapplications in many fields,such as the solar cell field,non linear o… 相似文献
64.
HUANG Yongmin XIAO Xingqing LIU Honglai** HU Ying Department of Chemistry Lab for Advanced Material East China University of Science Technology Shanghai China 《Chinese Journal of Reactive Polymers》2006,(2)
1. INTRODUCTION The extensive applications of block copolymer have been studied in detail due to their special molecular architecture and characteristic [1,2]. Recently, many studies including theoretical analysis and experimental techniques have addressed the polymer blend system of diblock copolymer/homopolymer [3~9]. An early investigation presented a quantitative analysis of homopolymer distributions in well-ordered copolymer microdomains through mixing polystyrene (PS) or poly methyl… 相似文献
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66.
Titanate nanoribbons were prepared via a hydrothermal treatment of rutile-type TiO2 powders in a 10 M NaOH solution at 200 °C for 48 h. The as-prepared titanate nanoribbons were then hydrothermally post-treated at 150 °C for 12-36 h. The titanate nanoribbons before and after hydrothermal post-treatment were characterized with FESEM, XRD, TEM, UV-VIS and nitrogen adsorption-desorption isotherms. The results showed that the hydrothermal post-treatment not only promoted the phase transformation from titanate to anatase TiO2, but also was beneficial to the removal of Na+ ions remained in the titanate nanoribbons. After hydrothermal post-treatment, the TiO2 samples retained the one-dimensional structure feature of the titanate nanoribbons and showed an obvious increase in the specific surface area and the pore volume. 相似文献
67.
Caseli L Masui DC Furriel RP Leone FA Zaniquelli ME 《Colloids and surfaces. B, Biointerfaces》2005,46(4):248-254
This work investigates the process of incorporation of a glycosylphosphatidyl inositol (GPI)-anchored alkaline phosphatase into Langmuir monolayers of dimyristoyl phosphatidic acid (DMPA). Three different methods of protein incorporation were assayed. When the protein solution was injected below the air–water interface after formation of the lipid monolayer a micro-heterogeneous distribution of alkaline phosphatase throughout the interface was observed. Adsorption kinetics studied by fluorescence microscopy, associated with surface pressure measurements, led to the proposition of a model in which the protein penetration is modulated by the surface packing of the monolayer and intermolecular interactions occurring between the phospholipid and the protein. At initial surface pressures higher than 20 mN m−1, the protein is quickly adsorbed on the interface and the lateral diffusion drives the alkyl chains to turn towards the air phase while the polypeptide moiety faces the aqueous subphase. 相似文献
68.
A series of PB-g-SAN impact modifiers with different ratio of PB to SAN ranging from 20.6/79.4 to 91.9/8.1 were synthesized by seeded emulsion polymerization. ABS blends were prepared by blending these PB-g-SAN impact modifiers and SAN resin. The rubber concentration of these ABS blends was kept at a constant value of 15 wt%. The influences of different impact modifier on the mechanical behavior and morphology of ABS blends have been investigated. The dynamic mechanical analysis on ABS blends shows that Tg of the rubbery phase shifts to a lower temperature, (tan δ)max of the rubbery phase increases and then decreases with the increase of PB concentration in PB-g-SAN impact modifier. A uniform dispersion of rubber particles in the matrix can be observed when PB/SAN ratio in PB-g-SAN impact modifier is in the range from 20.6/79.4 to 71.7/28.3. When it exceeds 71.7/28.3, an agglomeration of rubber particles occurs. The mechanical tests indicate that the ABS blend, in which PB/SAN ratio in the impact modifier is 71.7/28.3, has the maximum impact strength and yield strength. 相似文献
69.
Naoyuki Takahashi Arei Niwa Tadashi Takahashi Takato Nakamura 《Solid State Sciences》2003,5(11-12):1417-1419
The structural analysis of the hexagonal InN film prepared on a Si(100) substrate by the AP-HCVD technique using InCl3 and NH3 as starting materials were carried out by the X-ray pole figure analysis. The deposited films consist of the hexagonal InN pillar crystals. It was found that the pillar crystals, which have random rotation around the 100 axis, were grown at an angle of 70–90° to the substrate. 相似文献
70.