Patent FR-2794764-A1 (FR)
Title: Compositions based on organopolysiloxanes and silylated polymer, comprise mineral fillers and curing catalyst and are crosslinked into elastomer and adhesive in presence of moisture
Inventor: DALLIES CORINNE
IPC: C08L83/04
Filed: 1999-06-08
Abstract: The compositions are based on polyorganosiloxane(s) and silylated polyurethane(s). A mono-component composition, based on polyorganosiloxane(s) and silylated polyurethane(s), which is stable in the absence of moisture and crosslinking in the presence of moisture into a non-yellowing elastomer with adhesive properties, comprises: (1) 100 wt. parts of at least one linear crosslinkable polyorgano-polysiloxane (A) of formula (I); (2) 2-170 wt. parts of mineral fillers (G); (3) a curing catalyst (H) selected from amines and carboxylic acid salts of metals (Sn, Zn, Fe, Pb, Ba, and Zr), especially salts of fatty carboxylic acids (e.g. dibutyl tin dilaurate and dioctoate, iron stearate, tin (2+) octoate and lead octoate); from organic derivatives of titanium; and chelates, especially dibutyl tin bis (acetyl acetonate); (4) 1-20 wt. parts of at least one silylated polymer (C), of molecular wt. 300-100000, preferably 1000-50000, comprising at least two groups of formula (II), linked to polymer by intermediate 1-20C hydrocarbon chain, preferably alkylene, with polymer consisting of at least one -N-(C=O)-O- group, at least one -N-(C=O)-X- group (X being N, S, O or C) and may comprise other groups selected from esters, ethers, urea, amide isocyanurate and others; and (5) optionally up to 8 wt. parts of at least one adhesion promoting agent P on base of additional organosilicic compound selected from compounds bearing: (I) hydrolyzable groups linked to Si atom and (II) organic groups substituted with amino, isocyanato, epoxy, alkenyl and isocyanurate radicals. R<1>  = 1-13C monovalent (un)saturated, (non)substituted aliphatic, cyclic or aromatic hydrocarbon radical; R<2> = 1-13C monovalent (un)saturated, (non)substituted aliphatic, cyclic or aromatic hydrocarbon radical; R<3> = identical or different 1-8C linear or branched alkyl radical; n = sufficient to produce dynamic viscosity of A of 10<3>-10<6> mPa.s at 25 deg C; a = 0 or 1; and b = 0 or 1. R<4>a(OR<5>)3-a-Si-C(treble bond) (II) R<4> = 1-13C monovalent (un)saturated, aliphatic, cyclic and/or aromatic hydrocarbon radical which can be substituted e.g. by halogen; and R<5> = 1-8C monovalent (un)saturated, aliphatic, cyclic and/or aromatic hydrocarbon radical. The composition may also contain 0-50 wt. parts of non-reactive linear diorgano polysiloxane of formula (III); R<1>  = as for reactive polymer A; m = sufficient to produce dynamic viscosity of polymer equal 10-200000 mPa.s (preferably 50-150000 mPa.s) at 25 deg C. Preferably, R<1> is selected from: (a) 1-13C alkyl and haloalkyl radicals; (b) 5-13C cycloalkyl and halocycloalkyl radicals; (c) 2-8C alkenyl radicals; (d) 6-13C mononuclear aryl and haloaryl radicals; and (e) cyanoalkyl radicals with 2-5C alkyl chains. An Independent claim is also included for an elastomer adhesive to various substrates obtained by hardening of compositions as claimed at temperatures 5-35 deg C, in contact with moisture.