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1.
纳米AgBr/PMMA光致变色杂化材料制备与表征   总被引:4,自引:0,他引:4  
采用本体聚合法制备了纳米AgBr/PMMA(聚甲基丙烯酸甲酯)光致变色杂化材料. XRD分析表明,纳米AgBr/PMMA杂化材料是无定形的. SEM分析表明, AgBr含量不同,杂化材料的断面形貌明显不同,随AgBr含量的增加,杂化材料由韧性断裂向脆性断裂转变. EDS面分析表明, Ag、Br元素在杂化材料中均匀分布.所制备的纳米AgBr/PMMA杂化材料具有一定的光致变色效应.  相似文献   

2.
由共聚合在PMMA聚合物链段上引入了一-Si(OR)3为功能团,通过溶胶-凝胶过程合成了PMMA/TiO2杂化聚合物材料,溶剂抽提结构表明有化学键存在的杂化材料体系中凝胶的含量很高,通过FTIR测试材料结构进行了分析,由TGA,DSC测试分析了杂化材料体系中无机组份的含量材料性能的影响。  相似文献   

3.
纳米CeO2/PMMA杂化材料的制备与表征   总被引:16,自引:0,他引:16  
采用在位分散聚合法制备了纳米CeO2/PMMA杂化材料。XRD分析表明,杂化材料 是无定形的。SEM分析表明,杂化材料中CeO2含量不同,材料的断面形貌明显不同 ,随CeO2含量的增加,杂化材料由韧性断裂向脆性断裂转变。EDS面分析表明,Ce 在杂化材料中分布均匀。实验表明,随CeO2含量的增加,杂化材料的透过率与溶解 性降低。  相似文献   

4.
有机硅烷偶联剂在新材料中的一些特殊用途   总被引:12,自引:0,他引:12  
讨论了常用的有机硅烷偶联剂,在溶胶-凝胶法制备有机-无机杂化材料的时的化学反应,作用及使用方法,并与传统的应用进行了比较,对相关杂化材料的制备性能作了简要介绍。  相似文献   

5.
通过溶胶 凝胶过程合成了有机聚合物链段与无机相间有共价键存在的P(MMA MSMA)/TiO2 SiO2杂化聚合物材料.溶剂抽提结果表明杂化材料体系中凝胶的含量很高.通过FTIR测试对材料进行了结构分析,并且由TGA、DSC测试分别分析了杂化材料体系中无机组份总量以及Ti(OC4H9)4的含量对材料性能的影响.  相似文献   

6.
徐永群 《大学化学》1994,9(3):18-21
杂化指数及其化学信息徐永群(黄冈师范专科学校化学系湖北黄州436100)30年代初,Pauling为了解决化学键的方向性问题,引入了原子轨道杂化的概念,运用Lagrange乘因子法得到了sp、sp2、sp3和d2sp3等杂化原子轨道(HybridAt...  相似文献   

7.
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   

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.
采用脂肪酶为有机组分,Ca2+、Zn2+、Mn2+和Cu2+等4种金属磷酸盐为无机组分,制备脂肪酶-无机杂化纳米花,系统研究4种杂化脂肪酶的结构和催化活性。结果表明,制备的杂化脂肪酶具有花状的层级片状结构,并探究了无机杂化脂肪酶的最优反应时间为10 min,反应温度为40 ℃,pH为8。4种金属离子制备的杂化脂肪酶包封率达到90%以上。相比于游离脂肪酶,杂化脂肪酶的催化水解活性、催化反应速率、耐温性、耐变性剂均有所提高,其中Ca2+金属磷酸盐合成的杂化脂肪酶催化效率是游离脂肪酶的1.87倍,合成的杂化脂肪酶表现出良好的重复使用性。  相似文献   

10.
杂化材料的制备、性能及应用   总被引:37,自引:1,他引:36  
较详细地介绍了杂化材料的概念及其制备方法、性能和应用。重点是有机高分子-无机杂化材料的制备、性能及应用。  相似文献   

11.
PMMA-TiO2有机无机杂化玻璃的制备与表征   总被引:11,自引:1,他引:11  
有机无机杂化材料是随着对溶胶凝胶方法的广泛研究而发展起来的,有时它们被称为ORMOSILS(OrganicallyModifiedSilicates)[1,2]或ORMOCERS(OrganicallyModifiedCerandcs)[2].溶胶凝胶过程通过溶液化学(WetChemistry)的途径来形成无机骨架,在过去的几十年里,被广泛应用  相似文献   

12.
The possibility to prepare hybrids made by poly(vinyl acetate) (PVAc), poly(methyl methacrylate) (PMMA) and/or poly(ethyl acrylate) (PEtA) with TiO2 was studied. The processes of polymer formation-radical polymerization and sol-gel process for inorganic network —were achieved simultaneously. Due to a high reactivity of titanium isopropoxide (TIP) in the sol-gel process, a complexant comonomer, allyl acetoacetate (AlAcAc), was used. Covalent bonds between polymer and inorganic chains were obtained by addition of trialkoxysilane derivates with vinyl (VTES) or methacryloyl (MPTS) groups. The presence of TIP inhibits the radical polymerization of vinyl acetate (VAc). The PVAc-TiO2 hybrids were produced by the sol-gel process of TIP in the presence of pre-obtained PVAc. Except for VTES and MPTS, trialkoxysilane derivates with methyl (MeTES), octyl (OTES) and phenyl (PTES) groups were used. The thermal stability of hybrids is strongly affected by TiO2 presence and by the type of trialkoxysilane derivates. The thermal stability of PVAc hybrids decreases in the presence of TiO2 inorganic network. The glass transition temperature of polymers increases in the presence of the inorganic network.  相似文献   

13.
以正硅酸乙酯为前驱体,采用无溶剂水解技术,制备出了均一、稳定、透明的SiO_2溶胶,通过透射电子显微镜分析,粒径在100 nm左右;在溶胶中加入甲基丙烯酸甲酯(MMA)和偶氮二异丁腈(AIBN),采用热固化制备了透明的块体PMMA/SiO_2杂化材料,通过差热(DSC)和热重分析(TGA)研究了杂化材料的热性能. DSC结果表明,当体系中的SiO_2质量分数超过20%时,杂化材料无明显的玻璃化转变现象. TGA结果表明,杂化材料的分解温度提高约110 ℃. 透射电子显微镜观察结果表明,无机相均匀分散在有机相中,两相之间没有明显的相分离现象.  相似文献   

14.
由共聚合在PMMA聚合物链段上引入了-Si(OR)3功能团,通过溶胶-凝胶过程合成了PMMA/TiO2杂化聚合物材料.溶剂抽提结果表明有化学键存在的杂化材料体系中凝胶的含量很高.通过FTIR测试对材料结构进行了分析,由TGA、DSC测试分析了杂化材料体系中无机组份的含量对材料性能的影响.  相似文献   

15.
Poly(methyl methacrylate) (PMMA)/silica/titania ternary nanocomposites with covalent bonding interaction between polymer and inorganic phases have been prepared using a novel non-hydrolytic sol-gel method. Transmission electron microscope (TEM) image of silica/titania binary inorganic component indicates a core-shell-like structure. Scanning electron microscope (SEM) images suggest that the well dispersed silica/titania particles in the hybrid are on the nanometer-scale. The transparencies of nanocomposites are maintained in visible region while the absorption band in ultraviolet (UV) region is red shifted with increasing inorganic content. The thermogravimetric analysis (TGA) results show that the thermal stability of PMMA copolymer increases dramatically with the addition of silica/titania moieties both in nitrogen and in air.  相似文献   

16.
聚甲基丙烯酸甲酯/二氧化硅杂化材料制备与性能   总被引:23,自引:0,他引:23  
溶胶-凝胶;聚硅酸;聚甲基丙烯酸甲酯/二氧化硅杂化材料制备与性能  相似文献   

17.
PMMA/SiO2透明块体材料的热性能分析与微观结构表征   总被引:1,自引:0,他引:1  
毕于铁  任洪波  张林  王鲜  尚承伟 《应用化学》2009,26(10):1244-1246
以正硅酸乙酯为前驱体,采用无溶剂水解技术,制备出了均一、稳定、透明的二氧化硅溶胶,通过透射电镜分析,粒径在100nm左右;在溶胶中加入甲基丙烯酸甲酯(MMA)和偶氮二异丁腈(AIBN),采用热固化的方式制备出透明的块体PMMA/SiO2杂化材料,通过差热分析、热重和透射电镜表征杂化材料的热性能和微观结构,实验结果表明:当体系中的SiO2含量超过20%时,杂化材料无明显的玻璃化转变温度;无机相均匀分散在有机相中,两相之间没有明显的相分离现象,制备出均一的杂化材料。  相似文献   

18.
以乙烯基三氯硅烷为原料水解制得八乙烯基多面体低聚倍半硅氧烷(OV-POSS),将其与经KH570改性的SiO2溶胶和甲基丙烯酸甲酯(MMA)混合均匀,采用热固化的方法制得PMMA/SiO2/OV-POSS杂化材料,通过透射电镜、红外谱图、差热分析和热重分析对材料的微观结构以及热性能进行表征,结果表明:杂化材料结构均匀,有机相和无机相之间通过双键聚合的方式形成了共价键;杂化材料耐热性好,玻璃化转变温度比纯PMMA提高约72℃,分解温度提高约121℃。  相似文献   

19.
Organic/inorganic hybrid star‐like nanocomposites from two different octafunctional cubic silsesquioxane (CSSQ) nano‐cage cores and poly(methyl methacrylate) (PMMA) were synthesized using atom transfer radical polymerization (ATRP) at mild conditions, in which octafunctional octakis(3‐hydroxypropyldimethylsiloxy)octasilsesquioxane (OHPS) and octa(aminophenyl)silsesquioxane (OAPS) nano‐cages were used as ATRP initiators. The polymerization was carried out at 50 °C in acetonitrile/water mixture. 1H‐NMR and GPC were employed to characterize the obtained nanocomposites. GPC data revealed that the resulting nanocomposites exhibit unimodal and narrow molecular weight distributions indicating well‐controlled synthesis and well‐defined hybrid nanocomposites with star architecture. The influence of CSSQ nano‐cages on the thermal property of nanocomposites was investigated using differential scanning calorimetry and thermal gravimetric analysis (TGA). It was observed that the nanocomposites exhibit significantly higher glass transition temperature compared with its linear counterpart because of slow relaxation caused by the star‐like architecture. TGA study, however, did not reveal any significant improvement in thermal stability of nanocomposites as compared with linear PMMA. Finally, field emission scanning electron microscopy images of fractured surfaces of nanocomposite sample films showed well dispersed CSSQ nano‐cages in PMMA matrix without phase separation. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 766–776, 2008  相似文献   

20.
Poly(methyl methacrylate) (PMMA) nanocomposites containing (methacryloxy)propyl polyhedral oligomeric silsesquioxane (methacryl‐POSS) were prepared by bulk‐polymerization process. The structures of the products were characterized by FTIR, solid‐state NMR, TEM, XRD, DSC, TGA, XPS and UV‐Vis spectra. The hybrid materials were found to be largely homogeneous. DSC and TGA results indicate that the thermal properties of PMMA nanocomposites are significantly improved. The glass transition temperature (Tg) and thermal decomposition temperature (Tdec) of the nanocomposites increased by 58 and 110°C, respectively. The bulk hybrid material maintains excellent optical transparency in visible region.  相似文献   

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