US 11,655,404 B2
Sealant composition
Maude Desroches, Midland, MI (US); and Timothy Lueder, Midland, MI (US)
Assigned to DOW SILICONES CORPORATION, Midland, MI (US)
Appl. No. 17/786,398
Filed by DOW SILICONES CORPORATION, Midland, MI (US)
PCT Filed Dec. 17, 2020, PCT No. PCT/US2020/065475
§ 371(c)(1), (2) Date Jun. 16, 2022,
PCT Pub. No. WO2021/133622, PCT Pub. Date Jul. 1, 2021.
Claims priority of provisional application 62/952,522, filed on Dec. 23, 2019.
Prior Publication US 2023/0094559 A1, Mar. 30, 2023
Int. Cl. C09J 183/08 (2006.01); C09J 11/08 (2006.01); C09J 11/06 (2006.01); C09J 5/00 (2006.01); C08K 13/06 (2006.01); C08G 77/38 (2006.01); C08G 77/08 (2006.01); C08G 77/20 (2006.01); C09J 11/04 (2006.01); C08K 5/5419 (2006.01); C08K 5/544 (2006.01); C08K 9/00 (2006.01)
CPC C09J 183/08 (2013.01) [C08G 77/08 (2013.01); C08G 77/20 (2013.01); C08G 77/38 (2013.01); C08K 13/06 (2013.01); C09J 5/00 (2013.01); C09J 11/04 (2013.01); C09J 11/06 (2013.01); C08K 5/544 (2013.01); C08K 5/5419 (2013.01); C08K 9/00 (2013.01); C08K 2201/005 (2013.01); C08K 2201/006 (2013.01); C08K 2201/011 (2013.01); C08K 2201/014 (2013.01); C09J 2483/00 (2013.01)] 16 Claims
 
1. A one-part condensation curable low modulus room temperature vulcanisable (RTV) silicone composition comprising:
(a) an organopolysiloxane polymer having at least two hydroxyl or hydrolysable groups per molecule and of the general formula
X3-nRnSi—(Z)d—(O)q—(R1ySiO(4-y)/2)z—(SiR12—Z)d—Si—RnX3-n  (1)
in which each X is independently a hydroxyl group or a hydrolysable group, each R is an alkyl, alkenyl or aryl group, each R1 is an X group, alkyl group, alkenyl group or aryl group and Z is a divalent organic group; d is 0 or 1, q is 0 or 1 and (d+q)=1; n is 0, 1, 2 or 3, y is 0, 1 or 2, or optionally y is 2, and z is an integer such that organopolysiloxane polymer (a) has a viscosity of from 30,000 to 80,000 mPa·s at 25° C., or optionally from 40,000 to 75,000 mPa·s at 25° C., in an amount of from 35 to 60% by weight of the composition;
(b) a hydrophobically treated calcium carbonate reinforcing filler having a surface area of from 2.5 to 12 m2/g and an average particle size of >0.1 μm, in an amount of from 30 to 60% by weight of the composition;
(c) one or more difunctional silane chain extenders having two hydroxyl or hydrolysable groups per molecule, in an amount of from 0.2 to 5% by weight of the composition;
(d) a titanate and/or zirconate catalyst, in an amount of from 0.2 to 1.0% by weight of the composition; and
(e) an aminosilane adhesion promoter having two hydroxyl or hydrolysable groups per molecule, in an amount of from 0.1 to 3.75% by weight of the composition; and optionally, further comprising:
(f) one or more silane cross-linkers having at least three hydroxyl and/or hydrolysable groups per molecule, in an amount of from 0 to 3% by weight of the composition.