Organosiloxane compositions
AssigneeDow Corning Corporation
InventorsEmmanuel Jadot, Patrick Vandereecken
Life of this patent
Estimating the term…
Abstract
A one or more component moisture cure Organosiloxane composition that has strength in an uncured state (commonly referred to in the industry as “green strength”) and its uses. The composition comprises an organopolysiloxane polymer having a viscosity of at least 1000 mPa·s at 25° C. and not less than two silicon-bonded hydroxyl groups and/or silicon bonded hydrolysable groups; a suitable catalyst; a cross-linker adapted to react with organopolysiloxane polymer when catalysed with the catalyst; and optionally one or more rheology modifiers and 0 to 10% by weight of the composition of one or more extenders or plasticisers but in particular the composition contains a precipitated calcium carbonate filler in an amount of from 50 to 70 weight % of the total composition.
Claims19
A room temperature curable organopolysiloxane composition which has strength in an uncured state of at least 600 Pa measured after one minute, the composition consisting essentially of:
- a) from 20 to 45% by weight of an organopolysiloxane polymer having a viscosity of at least 1000 mPa·s at 25° C. and not less than two silicon-bonded hydroxyl groups and/or silicon bonded hydrolysable groups;
- b) a precipitated calcium carbonate filler;
- c) from 0.1 to 3% by weight of a metal containing condensation catalyst;
- d) from 1 to 10% by weight of a cross-linker adapted to react with component (a), catalysed with component (c);
- e) one or more rheology modifiers;
- f) 0 to 10% by weight of the composition of one or more extenders or plasticisers;
- and
- wherein component e) is chosen from silicone organic co-polymers based on polyols of polyethers or polyesters, polyethylene glycol, polypropylene glycol, ethoxylated castor oil, oleic acid ethoxylate, alkylphenol ethoxylates, copolymers of ethylene oxide (EO) and propylene oxide (PO), silicone polyether copolymers, carboxylated liquid polyolefins, carboxylated liquid butadienes, silicone glycols, and fumed silica, and
- wherein component b) is present in an amount of from 65 to 75% by weight of the total composition.
Dependencies are inferred from the claim text.