Organo-silanes silane

Primare Phosphine werden durch Reduktion von Phosphonsaureestern (vier Hy-drid-Aquivalenten eines Organo-silans) oder aus Dihalogen-phosphinen (zwei Hy-drid-Aquivalenten) bei 150-200° erhalten, wobei das Phosphin unmittelbar aus dem An-satz herausdestilliert werden kann z.B. ... 

Organo-silane werden durch Elektrolyse an der C-Metall-Bindung gespalten. So erhalt man z. B. aus Trimethyl-phenylathinyl-silan in Methylamin/Lithiumchlorid (s. a. S. 577) an Platin-Elektroden Phenyl-acetylen (38% d.Th.). Als Nebenprodukte fallen infolge Hydrierung Trimethyl-(2-phenyl-athyl)-silan (10% d.Th.) und A thy T benzol (30% d.Th.)... 

Preparation of Functionally Terminated Siloxane Oligomers via Controlled Hydrolysis of Organo-silanes... 

Schneider and Brebner (1985) impregnated wood samples with the organo-silane y-methacryloxypropyltrimethoxysilane (TMPS) (Figure 7.9a) and determined the dimensional stability as a resnlt of this treatment. Wood samples were conditioned to 6-8 % MC before being impregnated with a methanolic solution of the silane. The methanol was allowed to evaporate from the treated samples and they were then submerged in water to... 

The corrosion resistance and polymer-bonding compatibilities of the lonizable organophosphonates and the neutral organo-silanes are directly related to their inherent chemical properties. Specifically, NTMP inhibits the hydration of AI2O2 and maintains or Improves bond durability with a nitrile-modified epoxy adhesive which is cured at an elevated temperature. The mercaptopropyl silane, in addition to these properties, is compatible with a room temperature-cured epoxy-polyamide primer and also exhibits resistance to localized environmental corrosion. These results, in conjunction with the adsorbed Inhibitor films and the metal substrate surfaces, are subsequently discussed. 

Examples of the various methods of DNA immobilization are shown in Fig. 5. Amongst these are physical adsorption and covalent immobilization. The covalent immobihzation is best exemplified by the use of organo-silane chemistries and alkanethiol chemistries. 

Besides classical RPs with alkyl groups ranging from C4, frequently applied in peptide separations, to the work horses in HPLC C8 and C18, and up to C30 for the separation of long chain analytes, like carotinoids, many other organo silanes have been bonded to silica and used in HPLC. 

While organo-silane treatments are extensively used in both thermoset and elastomer applications, their use in thermoplastics has so far been somewhat restricted. This is because they do not react with the surface of calcium carbonate, one of the principal fillers used in this type of polymer and because of the lack of a suitable reactive functionality for most of the thermoplastic polymers. Today they are principally used in conjunction with glass fibres, calcined clays, aluminium and magnesium hydroxides, micas and wollastonite. The main thermo-... 

Table 3. Reactive functionalities carried by the principal organo-silane coupling agents for use in thermoplastics...

Complex organo-silane products are now emerging which seem able give significant improvements in the impact strength of highly filled polyolefins, especially when used in conjunction with metal hydroxide flame retardants [62]. This may significantly increase their use. 

As with fatty acids, organo-silanes can be applied by both wet and dry coating methods. In the present context, wet coating is principally restricted to glass fibre coating, where it can be incorporated into the size, which is already applied from water. Dry coating is the preferred method for coating mica, wollastonite clays and metal hydroxides. 

The second material is simply known as calcined clay and is formed when kaolin is heated above 1000 °C. This is an amorphous material with a defect spinel structure. A few isolated hydroxyls are retained on the particle surface and this enables the material to react with materials such as organo-silanes. 

The principal use of calcined clay in thermoplastics is in polyamide moulding compounds, for which purpose it is normally coated with an amino functional organo-silane. 

The production of mica for polymer applications has been reviewed by Hawley [89]. The aim of the processing is to purify the deposit and to produce particles of relatively small diameter with an aspect ratio of 50-200. The natural minerals are generally of much larger size than required and so the milling has both to delaminate and fracture the particles. The milling is the key process and a variety of methods, both wet and dry, are used, accompanied by various classification methods. Surface modification is important in many mica applications and a variety of treatments are used, especially organo-silanes. The methods of treatment are generally not disclosed. 

For example, in an investigation of silanes as adhesion promoters for ethylene/ vinyl acetate co-polymer encapsulants reported by Koenig et aL, the organo-silanes (referred to as primers ) were shown to generate primary chemical bonds at the polymer/substrate interface [27]. 

Me2SiCl2 from methyl chloride and elemental silicon. Hence, a facile method of transforming these by-products into new and useful organo-silanes is desirable. Atwell and Bokerman (58) report that the reaction shown in Eq. (94) can be catalyzed by a variety of means, and that the reaction is particularly favored when RX is an allyl halide. 

A typical embodiment for the porous layer technology is described in several patents and patent applications, e.g., a US patent application in 2006. This patent application describes a method for the preparation of silicon dioxide dispersions wherein the surface of the silicon dioxide is modified by treatment with the reaction products of a compound of trivalent aluminum with amino-organo-silane. The invention relates to recording sheets for inkjet printing having such a dispersion incorporated in the porous inkreceiving layer. Another US patent describes the preparation of nanoporous alumina oxide or hydroxide which contains at least one element of the rare earth metal series with atomic numbers 57 to 71. 

Organo-silanes and -stannanes possessing sp caibon-metal bonds also add to carbonyls in the presence of Lewis acids. Alkynylation with silyl- and stannyl-alkynes is promoted by AlCb or Z11CI2 (equations 9 and lO). " Notably, the reaction of l,3-bis(trimethylsilyl)-l-prcq>yne with chloral affords ynic alcohol instead of allenylic alcohol, showing the preferential cleavage of sp C—Si bonds (equation 11). ... 

Other organo-silanes and -stannanes are relatively inert, and addition reactions to aldehydes or ketones have been quite limited. However, there seems to be no reason why these organometals should not find applications in the future through the development of appropriate promoters. Actually, several examples appear in the literature. Aryl- or vinyl-silanes, which possess sp C—Si bonds, add to chloral in the presence of AICI3 (Scheme 2). The intramolecular addition reactions of alkylstannanes to ketones proceed with TiCU (equations 13 and 14). ... 

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