Silane polymerization

Results obtained with germanes also provide models for the kinds of reactions that may be occurring in the silane polymerization reaction as well. For example, we have succeeded in carrying out the reaction shown in Equation 4 (26). The analogous reactions with triphenylsilane, or triphenylstannane, were not... 

In recent work by Arkles el al. [4, 5], it has been proposed that, in comparison with monomeric silanes, polymeric silanes may react with substrates more efficiently. A typical polymeric silane is shown in Fig. la, in which pendant chains of siloxanes are attached through methylene chain spacers to a polyethyleneimine backbone. The film-forming polymeric silane thus provides a more continuous reactive surface to the polymer matrix in the composite. In this case, the recurring amino groups on the polymeric silane backbone can react with an epoxy resin matrix through chemical bond formation. 

FIGURE 10.1 Organosilane coupling agents react with water in aqueous solutions to form hydrolyzed silanes that react with the surface of inorganic fillers or the adherend. The bound silane polymerizes, building up layers outward, with the organic functionality oriented to the resin matrix.3... 

Silane polymerization spray with 50% pyridine/water, (CH3)2SiCl2... 

The chemistry of titanium is of considerable importance, primarily because of its roles as a catalyst in various chemical reactions (e.g., silane polymerization... 

Divalent titanium has been implicated as a catalyst in several reactions, including silane polymerization (1) and hydrosilation (2). Considerable theoretical effort has therefore been expended recently in analyzing the role of divalent titanium as a catalyst in the hydrosilation and bis-silylation reactions. 

Figure 3. Proposed mechanism for dehydrogenative silane polymerization by zirconocene and hafnocene catalysis.

The chemical vapour deposition of silane to the silicon surface minimizes the risk of silane polymerization [19, 20]. Our technique gives smooth silane layers of monolayer character as measured by ellipsometry. With an assumed refractive index for the silane of 1.46 [19] the thickness of the silane layer on the slides is measured by ellipsometry to be 6 1 A. 

The chemistry of titanium is of considerable importance, primarily because of its roles as a catalyst in various chemical reactions (e.g silane polymerization (1), hydrosilation (2), and Ziegler-Natta (3) polymerization), as materials and materials precursors, and as the basis for electronic and magnetic devices. In the past several years, the interest in titanium chemistry in this group has focused on its fundamental molecular and electronic structure in a variety of chemical environments, on its function as a catalyst in the hydrosilation and bis-silylation reactions, and on the nature of the structure, bonding, and mechanism of formation of metallocarbohedrenes. 

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