Dynasylan 40 Ethyl polysilicate Degussa-Silanes Abrasion Resistance Scratch/ Srcub/ Mar resistance agent Coatings Dynasylan® 40, a mixture of ethyl esters of different polysilicic acids, is, alongside the monomeric Dynasylan® A, the most industrially important of the silicic esters. Dynasylan® 40 is formed in the presence of water from tetraethyl silicate (Si[OEt]4) by partial hydrolysis of the ethoxy groups to hydroxyl groups and subsequent condensation with formation of siloxane bonds (-Si-O-Si-). Dynasylan® 40 is a colorless, low-viscosity liquid with an SiO2 content of 40%. The polysilicic acids still have a sufficient content of ethoxy groups which can be activated by acid- or base-catalyzed hydrolysis. Condensation starts even during hydrolysis, with the formation of relatively large polymeric molecules. During storage of these hydrolysates, condensation continues until a gel is formed, where the rate depends on the degree of hydrolysis. Dynasylan® 40 is also used as starting material for sol-gel processess. It is usually used in conjunction with alkylsilanes, organofunctional silanes and/or organic precursors(e.g. organic resins)to form siloxane networks. This makes it possible to obtain highly scratch-, abrasion-and chemical resistant coatings. Dynasylan® 40 or its hydrolysates are also the binder component for 1- and 2-pack zinc dust paints, crucial for corrosion protection on steel. Ethyl polysilicate. Used to obtain highly scratch-, abrasion-and chemical resistant coatings and as a binder for 1- and 2-pack zinc dust paints.