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Octadecyltrimethoxysilane
Octadecyltrimethoxysilane (OTMS) is an organosilicon compound. This colorless liquid is used for preparing hydrophobic coatings and self-assembled monolayers. It is sensitive toward water, irreversibly degrading to a siloxane polymer. It places a C18H39SiO3 "cap" on oxide surfaces. The formation of OTMS monolayers is used for converting hydrophilic surfaces to hydrophobic surfaces, e.g. for use in certain areas of nanotechnology and analytical chemistry. See also * Methyltrimethoxysilane * Octadecyltrichlorosilane References Further reading * * {{cite journal , doi = 10.1021/jp973334s, title = Langmuir Study of Octadecyltrimethoxysilane Behavior at the Air−Water Interface, journal = The Journal of Physical Chemistry B, volume = 102, issue = 7, pages = 1279–1286, year = 1998, last1 = Vidon, first1 = S, last2 = Leblanc, first2 = R. M Silanes Methoxy compounds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methyltrimethoxysilane
Methyltrimethoxysilane is an organosilicon compound with the formula CH3Si(OCH3)3. It is a colorless, free-flowing liquid. It is a crosslinker in the preparation of polysiloxane polymers. Preparation, structure and reactivity Methyltrimethoxysilane is usually prepared from methyltrichlorosilane and methanol: :CH3SiCl3 + 3 CH3OH → CH3Si(OCH3)3 + 3 HCl Alcoholysis of alkylchlorosilanes typically proceeds via an SN2 mechanism. Inversion of the configuration is favored during nucleophilic attack when displacing good leaving groups, such as chloride. In contrast, displacement of poor leaving groups, such as alkoxide, retention is favored.Colvin, W. Ernest, ''Silicon in Organic Synthesis'', Butterworth and Co Ltd, 1981. Methyltrimethoxysilane is tetrahedral and is often described as sp3 hybridized. It has idealized C3v Point group, point symmetry. Hydrolysis of MTM proceeds both under acidic and basic conditions. Under acid conditions, rates of successive hydrolyses for methyl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organosilicon Compound
Organosilicon compounds are organometallic compounds containing carbon–silicon chemical bond, bonds. Organosilicon chemistry is the corresponding science of their preparation and properties. Most organosilicon compounds are similar to the ordinary organic compounds, being colourless, flammable, hydrophobic, and stable to air. Silicon carbide is an ''inorganic chemistry, inorganic'' compound. History In 1846 Von Ebelman's had synthesized Tetraethyl orthosilicate (Si(OC2H5)4). In 1863 Friedel and Crafts managed to make the first organosilieon compound with C-Si bonds which gone byound the syntheses of orthosilicic acid esters. The same year they also described a «polysilicic acid ether» in the preparation of Ethanol, ethyl- and methyl-o-silicic acid. The early extensive research in the field of organosilicon compounds was pioneerd in the beginning of 20th century by Frederic Kipping. He also had coined the term «silicone» (akin to ketones) in relation to these materials ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coating
A coating is a covering that is applied to the surface of an object, usually referred to as the Substrate (materials science), substrate. The purpose of applying the coating may be decorative, functional, or both. Coatings may be applied as liquids, gases or solids e.g. Powder coatings. Paints and lacquers are coatings that mostly have dual uses of protecting the substrate and being decorative, although some artists paints are only for decoration, and the paint on large industrial pipes is for preventing corrosion and identification e.g. blue for process water, red for fire-fighting control etc. Functional coatings may be applied to change the surface properties of the substrate, such as adhesion, Wetting, wettability, corrosion resistance, or wear resistance. In other cases, e.g. semiconductor device fabrication (where the substrate is a wafer (electronics), wafer), the coating adds a completely new property, such as a magnetic response or electrical conductivity, and forms an e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Self-assembled Monolayer
Self-assembled monolayers (SAM) of organic molecules are molecular assemblies formed spontaneously on surfaces by adsorption and are organized into more or less large ordered domains. In some cases molecules that form the monolayer do not interact strongly with the substrate. This is the case for instance of the two-dimensional supramolecular networks of e.g. perylenetetracarboxylic dianhydride (PTCDA) on gold or of e.g. porphyrins on HOPG, highly oriented pyrolitic graphite (HOPG). In other cases the molecules possess a head group that has a strong affinity to the substrate and anchors the molecule to it. Such a SAM consisting of a head group, tail and functional end group is depicted in Figure 1. Common head groups include thiols, silanes, phosphonates, etc. SAMs are created by the chemisorption of "head groups" onto a substrate from either the vapor or liquid phase followed by a slow organization of "tail groups". Initially, at small molecular density on the surface, adsorbat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanotechnology
Nanotechnology, also shortened to nanotech, is the use of matter on an atomic, molecular, and supramolecular scale for industrial purposes. The earliest, widespread description of nanotechnology referred to the particular technological goal of precisely manipulating atoms and molecules for fabrication of macroscale products, also now referred to as molecular nanotechnology. A more generalized description of nanotechnology was subsequently established by the National Nanotechnology Initiative, which defined nanotechnology as the manipulation of matter with at least one dimension sized from 1 to 100 nanometers (nm). This definition reflects the fact that quantum mechanical effects are important at this quantum-realm scale, and so the definition shifted from a particular technological goal to a research category inclusive of all types of research and technologies that deal with the special properties of matter which occur below the given size threshold. It is therefore common to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Analytical Chemistry
Analytical chemistry studies and uses instruments and methods to separate, identify, and quantify matter. In practice, separation, identification or quantification may constitute the entire analysis or be combined with another method. Separation isolates analytes. Qualitative analysis identifies analytes, while quantitative analysis determines the numerical amount or concentration. Analytical chemistry consists of classical, wet chemical methods and modern, instrumental methods. Classical qualitative methods use separations such as precipitation, extraction, and distillation. Identification may be based on differences in color, odor, melting point, boiling point, solubility, radioactivity or reactivity. Classical quantitative analysis uses mass or volume changes to quantify amount. Instrumental methods may be used to separate samples using chromatography, electrophoresis or field flow fractionation. Then qualitative and quantitative analysis can be performed, often with t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Octadecyltrichlorosilane
Octadecyltrichlorosilane (ODTS or ''n''-octadecyltrichlorosilane) is an organosilicon chemical. It is used in semiconductor industry to form self-assembled monolayer thin films on silicon dioxide substrates. Its structural chemical formula is CH3(CH2)17SiCl3. It is flammable, reacts with water, and is also sensitive to air. It is corrosive and can severely damage mucous membranes. Its EINECS number is 203-930-7. Octadecyltrichlorosilane is an amphiphilic molecule consisting of a long-chain alkyl group (C18H37–) and a polar head group (SiCl3–), which forms self assembled monolayers (SAMs) on various oxidic substrates. ODTS finds its use in molecular electronics, as thin insulating gates in metal-insulator-semiconductor field-effect transistors. Dodecyltrichlorosilane, an ODTS analog with shorter alkyl chain, is used for the same purpose as well. ODTS-poly-4-vinylphenol, PVP films are used in organic-substrate LCD displays. References {{reflist Chlorosilanes Thi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silanes
Silanes refers to diverse kinds of charge-neutral silicon compounds with the formula . The R substituents can any combination of organic or inorganic groups. Most silanes contain Si-C bonds, and are discussed under organosilicon compounds. Examples: *Silane , the parent. *Binary silicon-hydrogen compounds (which are sometimes called silanes also) includes silane itself but also compounds with Si-Si bonds including disilane and longer chains. *Silanes with one, two, three, or four Si-H bonds are called hydrosilanes. Silane itself is the parent member. Examples: triethylsilane () and triethoxysilane (). *Polysilanes are organosilicon compounds with the formula . They include all binary silicon-hydrogen compounds except the parent, although these tend to be less useful because they are fragile. Attracting more interest, are the organic derivatives such as polydimethylsilane and dodecamethylcyclohexasilane *Chlorosilanes have Si-Cl bonds. Examples: trichlorosilane () and tetrachlo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
