Silanes chemical properties

In 1975, the fabrication of a chiral electrode by permanent attachment of amino acid residues to pendant groups on a graphite surface was reported At the same time, stimulated by the development of bonded phases on silica and aluminia surfaces the first example of derivatized metal surfaces for use as chemically modified electrodes was presented. A silanization technique was used for covalently binding redox species to hydroxy groups of SnOj or Pt surfaces. Before that time, some successful attemps to create electrode surfaces with deliberate chemical properties made use of specific adsorption techniques... 

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. 

The interfacial region modified by the silane has properties different from those of the bulk polyethylene. The crystallization in the interphase will be hindered due to the chemical bonds between the azidofunctional group and the polyethylene chains. Figure 6 shows this effect by a decrease of the heat of fusion (AH) with increasing number of silane layers for the composites with 20 and 50 vol% of glass. The AH values in Fig. 6 are in J/g polymer and were calculated from the values... 

Most chemical properties typical of tetraalkoxy(aroxy)silanes also characterise substituted ethers of orthosilicon acid, with the only difference that the reactivity of the ether group is greatly affected by the type and number of organic radicals directly at the silicon atom. 

A colloidal silica with 10-500 run particles can be prepared by the hydrolysis of tetraethoxysilane with aqueous ammonia. The particle morphology appears to be independent of the chemical properties of the silane but depends on the nature of the reaction medium. Large, irregularly shaped particles are produced at lower temperatures using solutions having a high ammonia concentration. Smaller, spherical particles result when the tetraethoxysilane concentration is low. ... 

The condensation of secondary silanes requires more rigorous conditions and no catalyst has yet been reported to couple tertiary silanes efficiently [140]. The great interest in polysilane polymers and their potential application come from their unusual electronic, optical, and chemical properties [142], particularly as preceramic materials [143]. The reaction constitutes the only alternative to Wurtz coupling for the formation of silicon-silicon bonds. 

Silicon has many similar chemical properties to carbon but its has a number of handicaps as a carbon analogue, however. Because silicon atoms are much bigger, they have difficulty forming double or triple bonds. Silanes (analogues of the alkanes) are highly reactive with water, and long-chain silanes spontaneously decompose. Molecules incorporating Si-O-Si bonds instead of Si-Si bonds are much more stable ordinary sand is one such example [60]. 

Using silane reagents which contain chemically active functional groups provides the necessary entrd into interface fabrication. For our purposes it was a question of matching the chemistry of the functional group with chemical properties that could be built into the Ru-bpy complexes. 

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