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1.
α-Silylmethylamines MeNHCH2SiMen(OMe)3?n (n=0, 2) were involved into Todd-Atherton reaction with (MeO)2P(O)H giving N-methyl-N-trimethoxysilylmethyl-and N-methyl-N-dimethyl-(methoxy)silylmethylamides of dimethylphosphoric acid. A reaction of these compounds with BF3·Et2O led to the formation of the corresponding N-methyl-N-trifluoro-and N-methyl-N-(dimethyl)fluorosilylmethylamides of dimethylphosphoric acid. (MeO)2P(O)N(Me)CH2SiF3 existed as an (O-Si)-chelate with a pentacoordinate silicon due to the occurrence of a rare and unstudied intramolecular coordinating interaction P=O → Si.  相似文献   

2.
A review is presented on those polymers which contain diphenylsilylene units and 1,3,4-oxadiazole rings either in the main chain or in the pendent groups. The synthesis of silicon-containing monomers as well as of the polyoxadiazoles based on them is described. The properties of these polymers, such as solubility, film forming ability, thermal stability, electrochemical behavior and photoluminescence properties, and their potential applications are discussed.  相似文献   

3.
近年来,含硅金属化合物由于在催化工业等领域的广泛应用受到了化学工作者的重视。本文综述了以硅原子或硅杂链为配体的桥形成的金属络合物、金属硅氧烷、硅-金属化合物、金属不饱和硅化物、含硅多金属络合物五种含硅金属化合物的研究进展。最后,并对该领域的研究方向提出了展望。  相似文献   

4.
Afanas'ev  A.V.  Antipov  O.L.  Benfield  R.E.  Bushuk  B.A.  Bushuk  S.B.  Domrachev  G.A.  Douglas  W.E.  Fominikh  Zh.  Jones  R.G.  Klapshina  L.G.  Kuzhelev  A.S.  Lopatina  Tatiana I.  Mustafa  Alkay  Rubinov  A.N.  Semenov  V.V.  Yurasova  Irena V.  Zinoviev  A.P. 《Silicon Chemistry》2002,1(2):145-154
A variety of novel poly[ethynediyl-arylidene-ethynediyl-silylene]s (PEAES), including those containing hypercoordinate silicon atom as well as donor and acceptor groups, has been synthesized. The presence of hypercoordinate silicon favours high values of fast Kerr-type non-linearities, and the incorporation of amide groups gives rise to good optical quality nanocomposites in a silica matrix. The inorganic-organic hybrid sol-gel film incorporating 5–14 mass% of the polymer containing pentacoordinate silicon showed Re (3) = –9.5 ×10–11 esu. The predominant rôle of the electron nonlinear mechanism has been demonstrated by using test beams with linear and circular polarizations. The photorefractive properties of composites based on PEAES as optical chromophores, poly(9-vinylcarbazole) as photoconductor, N-ethylcarbazole and phenyltrimethoxysilane as plasticizer, and fullerenes as charge generators have been investigated. The nonlinear optical effects, including four-wave mixing and two-beam coupling were studied at 633 nm without preliminary electric poling. The photorefractive origin of the refractive index changes was confirmed by the high two-beam gain under an externally applied electric field. Refractive index gratings affording two-beam gain can also be written under zero field conditions. To explain this unique property of the materials it is suggested that chromophore orientation asymmetry arises either during film formation or is induced by the longitudinal intensity gradient.  相似文献   

5.
Russian Journal of Applied Chemistry - A process was developed for chromate-free passivation of zinc-plated surfaces via formation of conversion silicon-containing coatings on these surfaces. The...  相似文献   

6.
Investigations were undertaken to obtain information for use in the development of new heat-stable polymers. Model silicon-containing Schiff base and benzimidazole derivatives were synthesized by reaction of p-(triphenylsilyl)-benzaldehyde with phenylenediamines. The structure and thermal stability of the products were studied. The reaction of p-(triphenylsilyl)benzaldehyde and o-phenylenediamine yielded N-p-(triphenylsilyl)benzylidene-o-phenylenediamine which readily oxidizes to form 2-p-(triphenylsilyl)phenylbenzimidazole. The di-Schiff bases, which most probably exist in trans-trans configurations, were obtained from reaction of the aldehyde derivative with m- and p-phenylenediamine. In contrast to similar Schiff bases without silicon, the products are soluble in organic solvents. The good resistance of the di-Schiff base and benzimidazole derivatives to thermal decomposition suggests that polymers with repeating units of such structures would also be heat-stable and might possess useful properties.  相似文献   

7.
配位有机硅在聚醚氨酯中的应用   总被引:3,自引:0,他引:3  
研究了直接从无定型二氧化硅出发,与乙二醇、氢氧化钾反应,生成高反应活性的五配位硅钾络合物,并以此为原料与2-氯乙醇反应制备双羟基四配位有机硅单体,该单体作为扩连剂再与异氰酸酯基封端的聚醚或聚酯进行低温溶液缩聚反应合成含硅聚醚氨酯,经红外光谱,热重分析,胶渗透色法测定分子量等对合成的物质作了结构表征,热重分析表明该聚合物的耐热性能有所提高,胶渗透色谱法测定分子量高于10万。  相似文献   

8.
硅基甲硫醇R^1R^2CH3SiCH2SH与O,O-二烷基二硫代磷酸酯(RO)2P(S)SH及甲醛可顺利地发生类Mannich缩合反应,利用此反应和硅基甲硫醇与O,O-二乙基-S(2-溴乙基)二硫代磷酸酯的取代反应合成了37种新的含硅二硫代到酯化合物(RO)2P(S)S(CH2)nSCH2SiCH3R^1R^2(n=1,2),在初筛浓度下,该类化合物具有一定的杀虫,杀螨活性。  相似文献   

9.
10.
汪静  林保平  袁春伟 《化学学报》2004,62(11):1019-1023,M003
以二氧化硅胶体晶体为模板,将由含硅的芳香二酐单体与芳香二胺单体在N,N-二甲基乙酰胺溶液中进行共聚得到的聚酰胺酸填入模板的空隙,经热环化,得到了二氧化硅/含硅聚酰亚胺复合物,再用氢氟酸除去二氧化硅模板,制备出了有序大孔含硅聚酰亚胺薄膜,通过扫描电子显微镜和紫外-可见光分光光度计对样品进行了表征.研究表明,所制备的含硅聚酰亚胺多孔薄膜,孔大小均匀、无收缩,在空间排布高度有序,其有序结构与模板中二氧化硅微球自组装方式完全相同,并且大孔之间由小孔互相连通.由于大孔的周期性排列,制备的薄膜表现出较好的光学特性.含硅聚酰亚胺兼具聚酰亚胺和有机硅树脂的优良性能,使制备的有序大孔薄膜在光电器件、催化、吸附、生物材料等方面具有十分重要的应用价值.  相似文献   

11.
含硅乙烯基醚单体的合成及光聚合反应   总被引:1,自引:0,他引:1  
本文采用含氯硅烷或硅氧烷与含羟基的单乙烯基醚的取代反应合成了8种含硅乙烯基醚单体,并研究了它们的物理化学性质和光聚合反应过程. 该合成反应过程简单、产率高,是合成含硅乙烯基醚单体的有效方法. 性质研究表明6种单体黏度合适,6种单体热稳定性好;光聚合反应研究表明,随着引发剂浓度(< 2.4wt %时)增加,单体聚合反应速率随之增大. 双官能度的单体在聚合速率和诱导期上表现整体优于单官能度单体. 含硅乙烯基醚单体的固化速率非常快,可以通过增加产酸剂浓度或光强来提高双键转化率.  相似文献   

12.
13.
This study reports the synthesis of new silicon-containing amide, benzimidazole hydrazide, and oxadiazole polymers. Procedures are described for the preparation of several intermediate compounds. The silicon-containing polymers are soluble in organic solvents. Solution-cast films from the polymers generally are flexible and exhibit good adhesion to glass and metal surfaces. Preliminary examination indicates that the polymers are heat-stable at elevated temperatures.  相似文献   

14.
Eric Magnusson 《Tetrahedron》1985,41(14):2945-2948
Substituent interaction energies are calculated by ab initio molecular orbital methods for the two series SiH2X- and SiH3X for the directly bound substituents X = BH2, CH3, NH2, OH, F and the results compared with those for the corresponding first row species. Interactions with the groups NH2, OH, F are as large in the neutral as in the anionic series and this is attributed to the presence of important π-bonding interactions, supplementing the effects of inductive withdrawal of σ-electrons. The restoration of charge neutrality by π-donation to silicon is more important in the neutral molecules, σ-electron transfer from silicon in the anions. π-Bonding with the π-acceptor substitutent BH2 is favourable, as it is in the CH3X and CH2X- systems, but with π-donor substituents the interactions are always destabilizing.  相似文献   

15.
Comparative analysis of cycling performance of hybrid electrodes based on the MAG synthetic graphite mechanic mixtures with silicon nanopowder and “nano-Si/SiO2/hard carbon” ceramic frame-ordered composite in 1 M LiPF6 solution in a monofluoroethylene carbonate-ethyl methyl carbonate mixture (30: 70, v/v), added with 3 wt % vinylene carbonate and 2 wt % ethylene sulfite, is performed. The high capacity loading (up to 6.8 mA h cm?2 at the electrode layer thickness of 37 μm) and acceptable accumulated irreversible capacity of the composite-containing electrodes are achieved, due to the electrodes’ high density and stable silicon-containing electrode/electrolyte interface formation.  相似文献   

16.
A low-waste method is proposed for synthesizing a mordenite-like zeolite from secondary silicon-containing raw materials.  相似文献   

17.
18.
以双[对-酰氯苯基]二甲基硅烷和酚酞、四溴酚酞以及双酚A为原料,合成了三种主链含硅聚芳酯,并对聚合物相关的物理性质进行了表征,制成了均质透明的薄膜.采用低真空法测定这些聚合物对H2、O2、N2、CO2、CH4的气体透过速率,并计算出气体透过系数、扩散系数、溶解系数、分离系数.从气体透过性能与聚合物分子结构关系的角度,按照气体透过的溶解-扩散机制,对聚合物的气体透过性能进行了研究,而且着重讨论了聚合物的堆积密度对气体扩散系数的影响,以及聚合物主链中极性链段的百分含量对气体溶解系数和溶解选择性的影响。  相似文献   

19.
20.
通过1-甲硫基亚乙基氨-甲基氨基甲酸酯与二氯亚砜反应,制得一系列新的含硅氨基甲酸酯衍生物.化合物结构经1 ̄HNMR、元素分析IR和MS确证,测定了化合物3a的晶体结构.生物测定结果表明,该类化合物对蚊子、粘虫、玉米螟等多种害虫具有优良的杀虫活性,且与母体灭多威相比,在哺乳动物安全性方面有显著提高.  相似文献   

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