GENIOSIL® GF 82
GENIOSIL® GF 82 is an epoxy functional alkoxysilane. It´s a clear, colorless liquid with a characteristic gasoline-like odor. It hydrolyzes slowly in the presence of water (ethanol is released). It form silanols, which can then react with themselves to produce siloxanes or can bind to inorganic substrates. The epoxy group on GENIOSIL® GF 82 can undergo a ring-opening reaction with nucleophiles such as alcohols and amines. An acidic or basic catalyst may be required. As a bifunctional, organically unsaturated molecule, GENIOSIL® GF 82 is able to function as a molecular bridge between inorganic and organic substrates.
1. General processing information
GENIOSIL® GF 82 is highly miscible with standard organic solvents, such as alcohols, hydrocarbons and acetone.
GENIOSIL® GF 82 is practically insoluble in neutral water. By incorporating a hydrolysis catalyst (e.g. acetic acid), hydrolysis can be greatly accelerated at pH values of 3 to 4. However, at pH values below 4, the epoxy ring may start to open.
Fillers are treated either with pure GENIOSIL® GF 82 or a solution thereof (e.g. in alcohol or an alcohol/water mix). It may be necessary to pretreat the substrate with water and/or a catalyst (e.g. ammonia). Subsequent binding of the treated filler, for example to epoxy resins, is preferably effected during the normal crosslinking process. In an alternative procedure referred to as "blending," GENIOSIL® GF 82 is added directly to the polymer - either before the filler is incorporated or at the same time. A prerequisite for the blending process is that GENIOSIL® GF 82 and the polymer are compatible and that the resin and GENIOSIL® GF 82 do not react prematurely.
Used as a primer, GENIOSIL® GF 82 is applied as a 0.5 - 2.5 percent solution (preferably organic) to an inorganic substrate (e.g. metal or glass surfaces) for example by spraying or knife coating. After < productname> has dried and bonded to the surface (postcure if necessary)techniquanic coating can be applied using a standard e (e.g. spraying, knife coating). In a further application, GENIOSIL® GF 82 can be used together with other hydrolyzable silicon compounds, such as silicates (e.g. SILICATE TES 28), as a constituent of aqueous solgel materials.
GENIOSIL® GF 82 is mainly used in the treatment of inorganic fillers (e.g. glass, mineral and glass wools, ATH, kaolin, mica, metallic oxides) for various polymer types, such as epoxy resins, urethane, melamine resins, EPDM, and for polysulfides, as a component of electronic potting compounds, as an additive or primer in coatings, paints, adhesives and sealants, and as a component of inorganic polysiloxane-based coatings.