共查询到18条相似文献,搜索用时 218 毫秒
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本研究合成出三种胆甾型液晶化合物,并用IR和DSC进行了表征.将三种液晶化合物与聚硅氧烷制成复合膜,测定其抗凝血性能,结果表明,亲水性愈高的复合膜血液相容性愈好. 相似文献
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从仿生学的角度设计和制备结构及组成与生物膜及血管内壁相似的聚合物/液晶复合膜,作为新一类抗凝血生物材料,并通过血液相容性试验考察复合材料的抗凝血性能.结果显示:不同基材及液晶种类的聚合物/液晶复合膜,其溶血率值均小于5%,符合生物材料溶血试验的要求;复合膜的动态凝血性能取决于基材与液晶两者之间的兼容性及配比,动态凝血性能较佳的复合膜表面粘附的血小板大多呈单个粘附状态,数量较少,且基本无变形,呈现出良好的血液相容性. 相似文献
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对聚醚砜进行磺化改性、对改性后的磺化聚醚砜进行肝素化改性,然后对聚醚砜、磺化聚醚砜和肝素化聚醚砜的力学性能和抗凝血性能进行了测试,结果表明:磺化改性后,聚醚砜材料的力学性能和抗凝血性能均有一定提高.经磺化改性再肝素化改性,聚醚砜材料优异的力学性能得以维持,聚醚砜材料的抗凝血性能提高明显,肝素化聚醚砜材料是一种良好的抗凝血材料。 相似文献
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PPC/PCU液晶复合膜的制备及其性能研究 总被引:1,自引:1,他引:0
采用溶液浇铸法和熔融法制备丙酰氧丙基纤维素/聚碳酸酯聚氨酯(PPC/ PCU)液晶复合膜.通过SEM、AFM、表面能量参数测定、溶血和动态凝血试验,研究了复合膜的表面形貌特征和血液相容性,考察了复合膜的制备方法和液晶含量对其性能的影响.结果表明,复合膜表面呈现微相分离结构,PPC液晶能明显改善PCU材料的血液相容性,改善的程度与复合膜中液晶的含量相关.由不同方法制备的复合膜,其表面的形态结构和表面能量参数不一样,采用溶液浇铸法制备的复合膜,其接触玻璃板的表面可见明显的海岛状微相分离结构,复合膜的血液相容性最好. 相似文献
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The graphene oxide sheets (GOs) reacted with 4,4′-diphenylmethane diisocyanate (MDI) and then stearic acid to form the functionalized graphene sheets (FGs), in order to improve their compatibility with isotactic polypropylene (iPP). The iPP incorporated with FGs were adequately mixed in a Haaker mixer and then compression molded to obtain the iPP/FGs nanocomposites. The crystallization, thermal stability and mechanical properties of the nanocomposites together with iPP/graphite sheets (Gs) and iPP/GOs composites were investigated by differential scanning calorimetry (DSC), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and tensile test. The FGs achieved good dispersion with exfoliated and intercalated nanostructure and strong interfacial adhesion with iPP, which made the nanocomposites have a significant enhancement of thermal stability and mechanical properties at low FGs loadings. 相似文献
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The present study explored the effect of nanoclay on the properties of the ethylene–propylene–diene rubber (EPDM)/carbon black
(CB) composites. The nanocomposites were prepared with 40 wt% loading of fillers, where the nanoclay percentage was kept constant
at 3 wt%. As the modified nanoclay contains the polar groups and the EPDM matrix is nonpolar, a polar rubber oil extended
carboxylated styrene butadiene rubber (XSBR), was used during the preparation of nanocomposites to improve the compatibility.
Primarily the nanoclay was dispersed in XSBR by solution mixing followed by ultrasonication. After that EPDM-based, CB–clay
hybrid nanocomposites, were prepared in a laboratory scale two roll mill. The dispersion of the different nanoclay in the
EPDM matrix was observed by wide-angle X-ray diffraction (WAXD) and high resolution transmission electron microscopy. It was
found that the mechanical properties of the hybrid nanocomposites were highly influenced by the dispersion and exfoliation
of the nanoclays in the EPDM matrix. Thermo gravimetric analysis, scanning electron microscopy and dynamic mechanical thermal
analysis was carried out for each nanocomposite. Among all the nanocomposites studied, the thermal and mechanical properties
of Cloisite 30B filled EPDM/CB nanocomposite were found to be highest. 相似文献
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《Materials Letters》2006,60(9-10):1306-1309
Polyurethane/epoxy resin interpenetrating network nanocomposites containing various contents of organophilic montmorillonite (oM-PU/EP nanocomposites) were prepared by a sequential polymeric technique and an in situ intercalation method. Transmission electronic microscopy and scanning electronic microscopy analysis showed that the interpenetrating process of PU and EP increases the exfoliation degree of organophilic montmorillonite (oMMT), and that oMMT improves the compatibility and phase structure of polyurethane/epoxy resin interpenetrating polymer networks (PU/EP IPNs). Tensile test, differential scanning calorimetry and thermal gravity analysis proved that the mechanical and thermal properties of the oM-PU/EP nanocomposites are superior to those of the pure PU and PU/EP IPNs. 相似文献
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The potential to improve the mechanical, thermal, and optical properties of poly(methyl methacrylate) (PMMA)/clay nanocomposites prepared with clay containing an organic modifier was investigated. Pristine sodium montmorillonite clay was modified using cocoamphodipropionate, which absorbs UVB in the 280–320 nm range, via ion exchange to enhance the compatibility between the clay platelets and the methyl methacrylate polymer matrix. PMMA/clay nanocomposites were synthesized via in situ free-radical polymerization. Three types of clay with various cation-exchange capacities (CEC) were used as inorganic layered materials in these organic–inorganic hybrid nanocomposites: CL42, CL120, and CL88 with CEC values of 116, 168, and 200 meq/100 g of clay, respectively. We characterized the effects of the organoclay dispersion on UV resistance, effectiveness as an O2 gas barrier, thermal stability, and mechanical properties of PMMA/clay nanocomposites. Gas permeability analysis demonstrated the excellent gas barrier properties of the nanocomposites, consistent with the intercalated or exfoliated morphologies observed. The optical properties were assessed using UV–Visible spectroscopy, which revealed that these materials have good optical clarity, UV resistance, and scratch resistance. The effect of the dispersion capability of organoclay on the thermal properties of PMMA/clay nanocomposites was investigated by thermogravimetric analysis and differential scanning calorimetry; these analyses revealed excellent thermal stability of some of the modified clay nanocomposites. 相似文献
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Carbon nanotube-based nanocomposites of chitosan were successfully prepared by a simple solution-evaporation method. Multiwalled carbon nanotubes (MWCNTs) were treated by poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate)(PEDOT-PSS) in water before mixed with a chitosan solution to improve the dispersion of MWCNTs and interfacial compatibility between MWCNTs and chitosan. The morphological and mechanical properties of the prepared PEDOT-PSS/MWCNT/chitosan nanocomposites have been characterized with field emission scanning electron microscopy (FESEM) and tensile tests. MWCNTs were observed to be homogeneously dispersed throughout the chitosan matrix. As compared with the neat chitosan, the tensile strength and modulus of the nanocomposite were greatly improved by about 61% and 34%, respectively, with incorporation of only 0.5 wt.% of MWCNTs into the chitosan matrix. The comparison of mechanical properties for PEDOT-PSS/MWCNT/chitosan and pristine MWCNT/chitosan nanocomposites has been made. The hardness of the nanocomposites was also evaluated by nanoindentation. 相似文献
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Effect of multi-wall carbon nanotubes on the mechanical properties of natural rubber 总被引:3,自引:0,他引:3
A. Fakhrul-Razi M.A. Atieh N. Girun T.G. Chuah M. El-Sadig D.R.A. Biak 《Composite Structures》2006,75(1-4):496-500
Multi-walled carbon nanotubes (MWNTs) were used to prepare natural rubber (NR) nanocomposites. Our first effort to achieve nanostructures in MWNTs/NR nanocomposites were formed by incorporating carbonnanotubes in a polymer solution and subsequently evaporating the solvent. Using this technique, nanotubess can be dispersed homogeneously in the NR matrix in an attempt to increase the mechanical properties of these nanocomposites. The properties of the nanocomposites such as tensile strength, tensile modulus, tear strength, elongation at break and hardness were studied. Mechanical test results show an increase in the initial modulus for up to 12 times in relation to pure NR. In addition to mechanical testing, the dispersion state of the MWNTs into NR was studied by transmission electron microscopy (TEM) in order to understand the morphology of the resulting system. According to the present study, application of the physical and mechanical properties of carbon nanotubes to NR can result in rubber products which have improved mechanical, physical and chemical properties, compared with existing rubber products reinforced with carbon black or silicone. 相似文献
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《Composites Science and Technology》2007,67(11-12):2350-2362
LDHs particles, including LDH-amino benzoate (LDHs-AB) and LDH-carbonate (LDHs-CB) particles, were prepared with coprecipitation method. After the intercalation of the amino benzoate, LDHs-AB particles have reactive and hydrophobic properties. In the preparation of the LDHs-AB/epoxy nanocomposites, the pre-intercalation of the EPON 828 resin into the LDHs-AB interlayer galleries prior to the addition of DDM curing agent was performed. Subsequently, after the addition of the DDM monomers, cross-linking polymerization was performed in the LDHs-AB intragalleries. It expands the interlayer space and well separates these nanolayers from one another to achieve the exfoliated nanocomposites. In addition, the strong chemical bondings formed from the reaction of the reactive LDHs-AB nanolayers and epoxy molecules lead to excellent compatible nanocomposites. Accordingly, exfoliated and compatible LDHs-AB/epoxy nanocomposites exhibit outstanding performance in thermal and mechanical properties compared to the pristine epoxy resin. On the contrary, LDHs-CB/epoxy nanocomposites exhibit a little enhancement on their properties because of the stacked lamellar LDHs-CB particles and weak compatibility in the epoxy nanocomposites. 相似文献