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71.
聚合物纳米复合材料的研究进展   总被引:2,自引:0,他引:2  
介绍了聚合物基纳米复合材料的种类及制备方法,详细介绍了聚合物/层状硅酸盐纳米复合材料的研究,包括聚合物/层状硅酸盐纳米复合材料的种类、性能及研究的新进展。  相似文献   
72.
改性磁性壳聚糖微球的制备、表征及性能研究   总被引:3,自引:0,他引:3  
王丽娟  刘峥  王莉 《应用化工》2007,36(2):105-108,116
以(NH4)2Fe(SO4)2.6H2O、NH4Fe(SO4)2.12H2O和壳聚糖为原料,经羟丙基化、胺基化,采用一步包埋法制备了一种新型的多胺基化磁性壳聚糖微球。通过正交实验法确定了磁性微球的最佳制备条件,即搅拌速度1200r/min,壳聚糖用量3.0g,环氧氯丙烷用量2.5mL,乙二胺用量2.5mL。并用IR、TG、XRD和SEM对其结构及形貌进行了表征。结果表明,Fe3O4磁性粒子已包埋了一层胺基化壳聚糖。磁性微球胺基含量为2.302mmol/g;呈较规则的球形,平均粒径为209nm,且具有顺磁性和良好的耐酸性。  相似文献   
73.
周超  戴红莲  李世普 《硅酸盐学报》2007,35(11):1423-1429
通过BaFe12O19硅烷偶联剂改性,聚乙二醇1000、甲苯二异氰酸酯在二甲苯溶液中预聚合,预聚物溶液在分散剂聚乙烯吡咯烷酮K30的水溶液中悬浮聚合,三步合成了BaFe12O19/聚氨酯复合微球.用扫描电镜、红外光谱仪、热重-差示扫描同步热分析仪和振动样品磁强计对微球的形貌、结构、玻璃化温度(Tg)和磁性能进行了表征.结果表明:合成的微球以BaFe12O19颗粒为核聚氨酯为壳.表面分布有微孔,微球粒径在400μm左右,粒径大小可通过控制反应条件调节.微球中磁性物质BaFe12O19的含量为11.11%(质量分数),Tg在290 ℃左右,耐热性能好,微球的饱和磁化强度为3.36×103 A/m,矫顽力为3.06×104 A/m.该复合微球是一种有潜在应用价值的新型血管内栓塞材料.  相似文献   
74.
Nanocomposites of iron oxide (Fe3O4) with a sulfonated polyaniline, poly(aniline‐co‐aminonaphthalenesulfonic acid) [SPAN(ANSA)], were synthesized through chemical oxidative copolymerization of aniline and 5‐amino‐2‐naphthalenesulfonic acid/1‐amino‐5‐naphthalenesulfonic acid in the presence of Fe3O4 nanoparticles. The nanocomposites [Fe3O4/SPAN(ANSA)‐NCs] were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X‐ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, elemental analysis, UV–visible spectroscopy, thermogravimetric analysis (TGA), superconductor quantum interference device (SQUID), and electrical conductivity measurements. The TEM images reveal that nanocrystalline Fe3O4 particles were homogeneously incorporated within the polymer matrix with the sizes in the range of 10–15 nm. XRD pattern reveals that pure Fe3O4 particles are having spinel structure, and nanocomposites are more crystalline in comparison to pristine polymers. Differential thermogravimetric (DTG) curves obtained through TGA informs that polymer chains in the composites have better thermal stability than that of the pristine copolymers. FTIR spectra provide information on the structure of the composites. The conductivity of the nanocomposites (~ 0.5 S cm?1) is higher than that of pristine PANI (~ 10?3 S cm?1). The charge transport behavior of the composites is explained through temperature difference of conductivity. The temperature dependence of conductivity fits with the quasi‐1D variable range hopping (quasi‐1D VRH) model. SQUID analysis reveals that the composites show ferromagnetic behavior at room temperature. The maximum saturation magnetization of the composite is 9.7 emu g?1. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007  相似文献   
75.
A series of novel hydrogel polysucrose microspheres with the mean size ranging from 200 to 500 μm were prepared via two‐step method. First, soluble polysucrose was synthesized by solution polymerization between sucrose and epichlorohydrin; second, a reversed phase suspension crosslinking reaction was performed to prepare polysucrose microspheres. The SEM images indicated that these spherical beads had smooth surface and hydrogel interior structure. FTIR was used to characterize the chemical structure of the beads. The hydrated and dry densities, equilibrium water content, and hydroxyl content of polysucrose microspheres were also investigated. The characteristic of high hydroxyl content (15.48–19.04 mmol/g) make these microspheres suitable for protein adsorption. Meanwhile, bovine serum albumin was used to examine the adsorption capacity of the microspheres. These microspheres had a capacity as high as 49.28 mg/g. The adsorption kinetics and recycling of the beads were also investigated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5934–5940, 2006  相似文献   
76.
使用海泡石制备环氧树脂纳米复合材料。采用胶化时间、热分析方法、红外光谱法研究纤维状海泡石对环氧树脂反应性的影响。用透射电镜观察海泡石的分散情况,通过力学性能的测试,研究海泡石对环氧树脂基体力学性能的影响。结果表明,海泡石对环氧树脂的工艺性没有影响,可使环氧树脂的力学性能大幅度提高。  相似文献   
77.
从聚合物/粘土纳米复合材料的相态结构、影响粘土插层解离和聚合物结晶行为的因素等方面对聚合物/粘土纳米复合材料的研究近况进行了综述。  相似文献   
78.
Polymer gel electrolytes were prepared by thermal crosslinking reaction of a series of acrylic end‐capped poly(ethylene glycol) and poly(propylene glycol) [P(EG‐co‐PG)] having various geometries and molecular weights. Acrylic end‐capped prepolymers were prepared by the esterification of low molecular weight (Mn: 1900–5000) P(EG‐co‐PG) with acrylic acid. The linear increase in the ionic conductivity of polymer gel electrolyte films was observed with increasing temperature. The increase in the conductivity was also monitored by increasing the molecular weight of precursor polymer. Nanocomposite electrolytes were prepared by the addition of 5 wt % of organically modified layered silicate (montmorillonite) into the gel polymer electrolytes. The enhancement of the ionic conductivity as well as mechanical properties was observed in the nanocomposite systems. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 894–899, 2004  相似文献   
79.
ABSTRACT

Recently, fabrication of polymeric nanocomposite via emulsion polymerization process has become a research spotlight. This review highlights the capability of emulsion polymerization technique to produce polymeric nanocomposite with tailored nanostructures, advanced properties, and high performance. Initially, overview on emulsion polymerization is presented. Afterward, advances in nanocomposites through the use of nanoparticles in emulsion polymerization have been elaborated. Main focus is given on the influence of graphene, carbon nanotube, carbon black, nanoclay, and inorganic nanoparticles on the essential features of emulsion polymerized nanocomposite. These materials have wide-ranging applications in coatings, adhesives, foaming/anti-foaming agents, packaging, paper/textiles, construction, and drug delivery fields.  相似文献   
80.
Poly(glycidyl methacrylate) (PGMA) beads with an average size of 350 μm were synthesized by suspension polymerization technique. The PGMA beads were first modified with iminodiacetonitrile (IDAN). Then, the IDAN‐modified beads were subsequently modified by hydroxylamine. The IDAN modification and the conversion of the nitrile groups to amidoxime were followed by FT‐IR spectroscopy. The surface morphology and thermal behavior of the PGMA and its modified forms were also characterized by scanning electron microscopy and thermogravimetric analysis techniques, further confirming modification and amidoximation. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007  相似文献   
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