| abstract |
(I) one or more condensation-curable silyl terminated polymers having at least one, typically at least two, hydrolysable and / or hydroxyl functional groups per molecule; (ii) a crosslinking agent selected from the group of silicon, organic polymers, silane or disilane molecules; And (iii) a condensation catalyst selected from the group of titanates, zirconates or tin (II), wherein the molar ratio of hydroxyl and / or hydrolyzable group in polymer (i) to hydrolyzable group Ratio is from 0.5: 1 to 1: 1 with a monosilane crosslinking agent or 0.75: 1 to 3: 1 with a disilane and the M-OR (where M is titanium or zirconium) or tin (II) Characterized in that the molar ratio of hydroxyl and / or hydrolysable group in the body polymer (i) is comprised between 0.01: 1 and 0.5: 1. Compositions, and uses of the gels are also described. |