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1.
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   

2.
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   

3.
通过原位本体聚合制备三异辛氧基混合稀土改性的聚苯乙烯,采用FT-IR,UV,FS和DMTA等手段研究三异辛氧基混合稀土对PS性能的影响,并测定其冲击强度。结果表明,改性PS的荧光强度随稀土含量的增加而提高;DMTA表明改性PS的玻璃化温度比纯PS的低,同时改性PS在低温-85度左右有一个较大的β转变峰,冲击强度亦有明显提高,说明改性PS具有较好的低温抗冲击性能。  相似文献   

4.
将无水三异丙氧基钐直接加入甲基丙烯酸甲酯(MMA)中会迅速形成凝胶,通过原位聚合可获得含钐的PMMA固体材料.研究表明,随钐含量的提高,含钐PMMA的结构逐渐由线型向交联网状体型转变,并使材料耐热性、耐溶剂性及贮能模量提高;ESEM表明,含钐PMMA呈交联网络蜂窝结构,未见聚集体,钐元素在体系中均匀分布;同时该材料呈现钐离子的特征荧光,在所测定的浓度范围内,荧光强度随钐含量增加而提高.  相似文献   

5.
三异丁氧基混合稀土增韧聚苯乙烯的研究   总被引:5,自引:0,他引:5  
通过原位本体聚合制备三异丁氧基混合稀土掺杂聚苯乙烯 ,采用FT IR、UV Vis、FS和DMTA等对其表征 ,并测定其冲击强度 .表明改性聚苯乙烯中存在着稀土金属离子和苯环的配位作用 ,改性聚苯乙烯的玻璃化温度随稀土含量增加而下降 ,但其抗冲性能显著提高 .说明三异丁氧基混合稀土对聚苯乙烯有明显的增韧改性作用  相似文献   

6.
定向聚合;有机/无机纳米杂化材料载体化钛催化剂的聚合研究Ⅱ.间同聚苯乙烯制备  相似文献   

7.
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   

8.
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   

9.
有机/无机纳米杂化材料负载钛催化剂及聚合研究 Ⅰ.乙烯聚合  相似文献   

10.
水凝胶微球即尺寸较小的球形水凝胶,除了凝胶特性外,其特点主要是具有较小的尺寸和球形形貌。由于其网络结构和快速的刺激响应性,使其作为模板制备具有独特性能的杂化材料而备受关注。本文主要从几个方面阐述了以微凝胶为基质制备杂化材料的方法及其应用。包括了磁性金属氧化物-凝胶杂化材料、金属单质-凝胶杂化材料、生物活性-凝胶杂化材料及功能化的球形和膜状杂化材料,最后介绍了本实验室以微凝胶为基质制备表面图案化杂化材料的方法。  相似文献   

11.
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   

12.
周莅霖  况锦铭  袁金颖 《化学进展》2009,21(9):1880-1887
四氧化三铁聚合物微球因其结合了纳米四氧化三铁的超顺磁性和有机聚合物的多种特殊性质,如生物相容性、刺激响应性、荧光性,良好的分散性等,而在生物、医学、催化、分离等领域有着重要的应用前景,得到了深入研究。本文按聚合方法分类,综述了利用普通自由基聚合、原子转移自由基聚合(ATRP)、可逆加成断裂链转移聚合(RAFT)、氮氧稳定自由基聚合(NMRP)、活性开环聚合(ROP)等方法在四氧化三铁纳米粒子表面进行接枝聚合制备磁性聚合物微球的研究进展。  相似文献   

13.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
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   

19.
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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20.
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   

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