In the presence of water, the alkoxy group of CFS-475 [CAS 65799-47-5 Z-6044; KBM-402] is hydrolysed to form a reactive silicone hydroxyl group, which releases methanol as a by-product of the hydrolysis reaction. This silicone hydroxyl group will be condensed with the hydroxyl group on the surface of various inorganic materials (substrates or fillers) to form a chemical bond, while its epoxy group can be subjected to heat or the action of acid or alkali catalyst to epoxy ring opening reaction and chemical reaction with suitable polymers (containing primary amino group, hydroxyl group, carboxyl group, epoxy group, acid anhydride, etc.). The product enables the coupling and joining of inorganic fillers (or substrates) with organic polymeric materials. 

The hydrolysis of CFS-475 requires the use of organic acids (e.g. formic acid, acetic acid, etc.) as catalysts. Specifically, the pH of the water is adjusted to 4.5 to 5.0 with weak organic acids (formic acid, acetic acid, etc.), where the hydrolysis of the silane is fastest and the self-polymerisation is slowest, and where the premature ring opening of the epoxy groups due to the high acidity is prevented. The acidified water should be added to the silane and stirred for a period of time (at least 15 minutes) until the silane is completely dissolved and the solution is clear and transparent. Its hydrolysate is unstable and it is recommended to use it up within 24 hours. A foggy solution means that the silane has partially self-polymerised to form a silane polymer (silicone) and has failed.

Suitable inorganic materials for this product include glass, glass fibre, glass wool, mineral wool, mica, quartz and other siliceous materials and metals and their oxides such as aluminium hydroxide, magnesium hydroxide, kaolin, talc, steel, zinc and aluminium, but it is basically ineffective on fillers that do not contain hydroxyl groups on their surface such as calcium carbonate, graphite, carbon black and barium sulphate.

Suitable polymers for this product include (but are not limited to) phenolic, epoxy, urea-formaldehyde, polyurethane, acrylic, polyester, silicone, polysulphide, PVAC and other resins and plastics such as nylon, PBT and PET.