Silane applications

Silane drying Blow excess silane off panel with 30 psi dry, oil-free N2. Place in preheated 220°F (I04 C) circulating air oven for 1 h. Blow excess silane off panel with dry, oil-free Nr. Use heat lamps or other heating sources to maintain 200-220°F (93-104°C) for 1 h. Use appropriate thermocouples to assure temperature and uniformity. The time between silane application and stall of heating should be minimized and no more than 1 hour. 

Mixed Organofluorine - Organosilicon Chemistry. Part 9. Aldol Reactions of Acylsilanes and (Difluoroenoxy)silanes. Application to the Synthesis of 2-Fluoro 1,3-Diketones ... 

In order to realize, in practice, the coupling effects of silanes, it is necessary to standardize the conditions of application such that the silane is able to provide a molecular bridge without itself becoming a weak interphase between the fiber and matrix. As already mentioned, the principal experimental parameters to be controlled in the application of silane coupling agents on the fibers are the concentration, the solvent, and the treatment time. In order to arrive at the best conditions for each parameter, the IFSS was determined for each set of treatment conditions. Optimization of the conditions of silane application was thus progressively achieved. 

When the treatment times for silane application were varied up to 30 min immersion of the fibers in 0.5% aqueous silane solution, it was found that the... 

The improvements in fiber-matrix bonding brought about by the application of silane coupling agents should be reflected in the results of IFSS measurement using the SFC specimen. The relative merits of the three silanes studied here can thus be compared through the IFSS values obtained under optimal conditions of silane application in each case. These results are presented in Figs 6 and 7. 

Enhancement of a flexible PVC-silica composite interface was studied by the application of gamma-aminopropyltrimethoxysilane on silane. Composites containing silica and silanised silica up to 25.6 phr and prepared by sol-gel technology were subjected to water and water vapour attacks similar to that in their daily use. Silane application resulted in diminishing liquid water and water vapour sorption by about 24.0% and 11.9%, respectively. Inhibition of dioctyl phthalate migration from composites by silane application was also determined as 24% using UV measurements. 20 refs. TURKEY... 

The way the application of this silane was described in this specihc reference makes it dubious for an industrial process. Cellulose hber was hrst dewaxed in an alcoholic solution for 24 h, and then was washed with distilled water and treated with the silane component (2% w/w) in an alcoholic solution for 24 h. The silane application was hnished with a 4-h drying process in a vacuum at 75°C [10],... 

Within the whole organic and inorganic silicon industry organofiinctional silanes represent only a small part of the cake. Nevertheless, these small molecules are basically present in everyday life, in most cases rather hidden. Figure 2 shows the variety of silane applications in industry. 

Abel, M.L., AUington, R.D., Digby, R.P., Porritt, N., Shaw, S.J., Watts, JJ7 (2006) Understanding the relationship between silane application conditions, bond durability and locus of failure. Int. J. Adhes. Adhes., 26,2-15. 

Under basic conditions the hydrolysis of alkoxy groups takes place during the silane application process, and generally occurs in a stepwise fashion. Except for aminosilanes, however, it is usual to employ acid conditions. The rate of hydrolysis of alkoxy groups decreases with an increase in their size, for instance FTIR evidence indicates that vinyl tri-methoxysilane hydrolyses almost eight times as quickly as the triethoxy equivalent. The glass surface is likely to become covered with several monolayers of hydrolysed silane. 

First and foremost, the cleanliness of the substrate should be of uppermost importance but is not always necessary, which confuses the silane application issue further. Usually, one should... 

The first silane applications in mbber tires used mercaptosilane to modify siliea and clay fillers. Commercial applications were limited to specialty areas, such as white sidewall components, some tread stocks, and some off-road tires, but processing and physical property deficiencies limited commercial applications. However, Degussa Corporation, which... 

The properties and applications of commercially important hydride functional silanes, ie, compounds having a Si—H bond halosilanes, ie, compounds having a Si—X bond and organosilanes, ie, compounds having a Si—C bond, are discussed hereia. Compounds having Si—OSi bonds are called sdoxanes or sihcones. Those having a Si—OR bond are called siUcon esters. Sdoxanes and siUcon esters are discussed elsewhere ia the Eniyclopedia (see Silicon COMPOUNDS, SILICON ESTERS SILICON COMPOUNDS, SILICONES). 

Vulcanised (cross-linked) polyethylene is being used for cable application where service temperatures up to 90°C are encountered. Typical cross-linking agents for this purpose are peroxides such as dicumyl peroxide. The use of such agents is significantly cheaper than irradiation processes for the cross-linking of the polymer. An alternative process involves the use of vinyl silanes (see Section 10.9). 

The composition of an epoxide moulding material will greatly depend on the specific application, and this has been discussed at length. ". The resin may be of the epoxide novolac type and there will also be present hardeners, fillers (such as silica), a silane coupling agent, pigment, flame retardant and a wax release agent. 

In primer formulations for adhesive bonding of metals, the coupling agents that are most frequently used are those based on epoxy and amine functionalities. Aqueous solutions of aminosilanes have been successfully used for obtaining stable adhesive bonds between epoxy and steel [10] and epoxy and titanium [11,12], while epoxy functional silanes are preferable for applications involving aluminum substrates [13,14], A simple solution of % epoxy functional silane in water is currently used for field repairs of military aircraft [15] where phosphoric acid anodization would be extremely difficult to carry out, and performance is deemed quite acceptable. 

Adhesion promoter. Epoxy silane can be added to increase adhesion to glass (mainly for BR sealants). In certain textile applications, isocyanates can be added to solvent-borne BR cements. 

Cured phenolics are universally brittle in nature. This is true of both resoles and novolacs and does not depend much on the source of methylene used to promote cure. Consequently, the fillers used in molded articles are highly important to the design of the manufactured product. With resoles, the fiber or filler are usually the primary component of the final composite, with the resole acting as a binder or impregnating agent. With novolacs the resin may be the major component in the molded part. Poly-silanes and other organic polymers are also added in some applications to promote impact resistance and toughness [192]. 

One issue with the GBS treatment (and silane-coupling treatments, in general) is that the performance can be highly dependent on processing conditions, especially hydrolysis and drying conditions. Nonetheless, process controls suitable for field application of bonded repair patches are possible. 

---