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非水凝胶原位聚合法制备三异丙氧基钕/PMMA杂化材料的研究 总被引:8,自引:0,他引:8
通过三异丙氧基钕直接掺入MMA单体 ,迅速形成凝胶后进行原位聚合的方法制得三异丙氧基钕 /PMMA杂化材料 ,采用IR、TG、WAXD、DMTA、SEM等手段对其进行表征 .结果表明 ,三异丙氧基钕与MMA中的羰基因配位并导致交联形成了交联网状结构的杂化材料 .与PMMA相比 ,这种杂化材料具有优良的耐热性、耐溶剂性 ,高贮能模量 ,同时 ,该制备方法克服了稀土离子易缔合的缺点 ,获得了高稀土含量且均匀分布的三异丙氧基钕 /PMMA杂化材料 相似文献
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在氮气保护下, 将一定比例的甲基丙烯酸甲酯(MMA)注入装有三异丙氧基铒的密闭容器中, 混匀后, 迅速形成淡红色凝胶体, 此凝胶体原位聚合后即制得三异丙氧基铒掺杂的PMMA固体试样(Er/PMMA), 研究三异丙氧基铒掺杂对PMMA性能的影响. EMTA、 TG表明, Er/PMMA的玻璃化温度比纯PMMA低, 但耐热性能与贮能模量均比PMMA的高; FS、 IR 表明, Er/PMMA 中的Er(Ⅲ)离子与羧基存在着配位作用, 使Er/PMMA的荧光强度明显提高; 同时Er/PMMA是一种具有一定透明性和光选择吸收性的高分子材料. 相似文献
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非水凝胶原位聚合制备Tb(OPri)3 掺杂的P(MMA-co-St)共聚物的研究 总被引:3,自引:0,他引:3
将三异丙氧基铽[Tb(OPr^i)3]直接掺入甲基丙烯酸甲酯(MMA)与苯乙烯(St)的混合单体中,混匀后会立即形成白色凝胶体,通过原位聚合后即获得掺杂Tb(OPr^i)3的P(MMA-co-St)共聚物。采用FT-IR,DMTA,TG,FS,ESEM等手段对其进行表征。FT-IR分析表明,共聚物中Tb^3 离子与羰基和苯环间存在着配位作用;MMA与St主要以交替共聚为主。DMTA,TG表明,Tb(OPr^i)3的掺入,使共聚物的玻璃化温度下降、贮能模量和耐热性能提高。FS分析表明,当Tb含量为1.0%时,共聚物在381nm处发射宽而强的荧光,其强度约是纯P(MMA-co-St)的14倍,同时在489,544,584nm处发射很强的Tb^3 离子^5D4→^7F6,^5D4→^7F5,^5D4→^7F4跃迁的特征荧光。ESEM表明,共聚物呈现交联网络状的微观形貌,未见聚集体,Tb^3 离子在体系中是均匀分布的。 相似文献
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介绍了溶胶–凝胶法制备有机/无机杂化材料的原理和基本过程,杂化材料的制备方法及对材料性能的影响,概述了杂化材料在结构材料、光学材料及其它材料中的应用研究。 相似文献
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Oun-Ho Park Young-Joo Eo Yoon-Ki Choi Byeong-Soo Bae 《Journal of Sol-Gel Science and Technology》1999,16(3):235-241
Structural evolution and optical properties of the silica-poly(ethylene oxide) hybrid films prepared from -glycidoxypropyltrimethoxysilane (GPTS) and 1-methylimidazol (MI) are studied. Polymerization of the epoxy groups is achieved by using 1-methylimidazol as a thermal curing agent. In liquid state 1H &13 C NMR spectroscopy, it is found that silica condensation mainly occurs without epoxy ring opening. The epoxide polymerization is confirmed by using FT-IR, solid state CP-MAS 13C-NMR, and differential scanning calorimetry (DSC). The hybrid material is densified due to the epoxide polymerization as well as silica condensation with thermal curing. As a result, the thermal curing increases refractive index and extinction coefficient and shifts UV optical absorption edge to longer wavelength. 相似文献
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In this article, the poly(methyl methacrylate)/montmorillonite (PMMA/MMT) organic-inorganic hybrid materials were prepared by conventional free radical polymerization and reversible addition-fragmentation chain transfer (RAFT) polymerization, respectively. The kinetics comparison of these two polymerizations was studied. The PMMA/MMT hybrid materials were characterized by gel permeation chromatography (GPC), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). According to these results, we knew that the polymerization behavior of MMA showed controlled/living radical polymerization (CLRP) characteristics under the control of RAFT agent. The incorporation of RAFT agent and MMT nanoparticles improved the thermal properties of polymers, and the thermal stability of polymers increased with increasing content of MMT nanoparticles. The structures and morphologies of PMMA/MMT hybrid materials were characterized by FT-IR, XRD and TEM. These results showed that the MMA monomer can be initiated and propagated in the clay layers of MMT via the control of RAFT agent, and then the exfoliated structure was obtained for the hybrid materials. 相似文献
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Sebastian Scharf Sebastian Notz Rico Thomas Prof. Dr. Michael Mehring Prof. Dr. Christoph Tegenkamp Dr. Petr Formánek Dr. René Hübner Prof. Dr. Heinrich Lang 《欧洲无机化学杂志》2023,26(9):e202200663
Twin monomers [Mg(2-OCH2-cC6H4O)][L]0.8 ( 2 , L=diglyme) and [Mg(2-OCH2-cC6H4O)][L]0.66 ( 3 , L=tmeda) form by their thermal polymerization interpenetrating organic-inorganic hybrid materials in a straightforward manner. Carbonization (Ar) followed by calcination gave porous MgO ( 2 : surface area 200 m2 g−1, 3 : 400 m2 g−1), which showed in catalytic studies towards Meerwein-Ponndorf-Verley reductions excellent yields and complete conversions for cyclohexanone and benzaldehyde. However, with crotonaldehyde a mixture of C4–C8 compounds was obtained. When MgO was exposed to air then primarily crotyl alcohol was formed. The range of applications could be easily extended by twin polymerization of 3 in presence of [Cu(O2CCH2O(CH2CH2O)2Me)2] ( 4 ) or [Ag(O2CCH2-cC4H3S)(PPh3)] ( 5 ), resulting in the formation of nanoparticle-decorated porous CuO@MgO or Ag@MgO materials, which showed high catalytic reactivity towards the reduction of methylene blue. 相似文献
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讨论了溶胶 -凝胶法合成有机 /无机杂化聚合物材料中的增容剂的应用 ,并详细介绍了三类增容剂的结构、增容机理和性能。 相似文献
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等离子体引发原位聚合制备凹凸棒土/聚苯乙烯纳米复合物 总被引:7,自引:0,他引:7
用阳离子表面活性剂处理凹凸棒土(Attapulgite),通过超声分散的方法将其均匀分散到苯乙烯单体中,并采用等离子体引发的方法制备出凹凸棒土/聚苯乙烯纳米复合物。通过透射电子显微镜(TEM)和X-射线衍射(XRD)观察了凹凸棒土及其纳米复合物的微观结构。对复合物的GPC测试表明,采用等离子体引发聚合反应可以显著提高树脂的分子量。XRD结果表明聚苯乙烯不是嵌入到凹凸棒土的层间,而是通过离子吸附接枝在凹凸棒土的棒状晶束上。 相似文献
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近年来,氧化石墨烯/金银纳米粒子复合材料由于其优异的表面增强拉曼散射(SERS)性能引起了人们极大的关注,在污染物检测、化学传感和癌症诊断等领域具有重要的应用价值。本文综述了氧化石墨烯片层上修饰金银纳米粒子、氧化石墨烯包覆金银纳米粒子、氧化石墨烯附着在金银纳米粒子层三种氧化石墨烯/金银纳米粒子复合材料的制备方法,对其SERS效应进行了详细介绍。SERS研究表明,结合了金银纳米粒子与氧化石墨烯两种材料各自在SERS研究与应用中的优势,氧化石墨烯/金银纳米粒子复合材料的SERS性能比单纯金银纳米粒子更加优异。氧化石墨烯在其中起到了化学增强、分子富集、钝化保护、荧光猝灭的重要作用。氧化石墨烯/金银纳米粒子复合材料在表面增强拉曼光谱中具有广阔的应用前景。 相似文献
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Serials of halloysite nanotubes/polystyrene (HNTs/PS) nanocomposites with different contents of organo-modified halloysite
nanotubes (organo-HNTs) were successfully prepared by the in situ bulk polymerization of styrene with the organo-HNTs as macromonomers.
The percentage of grafting (PG%) of more than 230% was achieved, calculated from the results of the thermogravimetric analysis
(TG). The TG results also showed that the thermal stabilities of the HNTs/PS nanocomposites prepared via the bulk polymerization
were better than the pure polystyrene. And the maximum thermal degradation temperature of the nanocomposites increased with
the increasing of the amount of the HNTs fillers added. 相似文献
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Acrylate–alkyd hybrid latex via miniemulsion polymerizations show promise as water‐borne coating systems. However, poor homogeneity of the particles caused by the immiscibility of the alkyd in polyacrylate limits monomer conversion and film formation. To resolve this problem, the hybrid miniemulsion polymerization of acrylate in the presence of linoleic acid and sunflower seed oil was carried out. Products were characterized by solvent extraction, dynamic light scattering, gel permeation chromatography (GPC), differential scanning calorimeter (DSC), and transmission electron microscopy (TEM). The results provide clear evidence that substituting a fatty acid or natural oil with smaller molecular size (weight) for a conventional alkyd improves the grafting efficiency, and enhances the homogeneity of the hybrid polymer particles in water‐borne latex systems.
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原位聚合制备聚乙烯/蒙脱土(MMT)纳米复合材料的研究 总被引:12,自引:0,他引:12
利用MgCl2在醇中溶解和蒙脱土(MMT)在醇中层间膨胀的特性,制备了MgCl2/TiCl4负载于MMT层间的MMT/MgCl2/TiCl4催化剂,并通过原位聚合合成了聚乙烯/蒙脱土纳米复合材料.经广角X射线衍射(WAXD)和透射电子显微镜(TEM)分析表明,蒙脱土片层在乙烯聚合过程中发生了层间剥离,以单片层或几片层共存的形式无规地分散于聚乙烯基质中.与分子量相近的纯聚乙烯相比,极低的蒙脱土含量(质量分数<1%)能使复合材料的屈服强度、拉伸强度和拉伸模量有很大提高.复合材料中蒙脱土片层以纳米尺寸在聚乙烯基质中的良好分布和对聚乙烯分子链运动的限制作用是力学性能提高的主要因素. 相似文献