Thickening silicones with elastomeric silicone polyethers
First Claim
1. A method of making a silicone elastomer comprising reacting:
- (A) an .tbd.Si--H containing polysiloxane of the formula R3 SiO(R'"'"'2 SiO)a (R"HSiO)b SiR3 or the formula (R'"'"'2 SiO)a (R"HSiO)b, and optionally an .tbd.Si--H containing polysiloxane of the formula HR2 SiO(R'"'"'2 SiO)c SiR2 H or an .tbd.Si--H containing polysiloxane of the formula HR2 SiO(R'"'"'2 SiO)a (R"HSiO)b SiR2 H, where R, R'"'"', and R" are alkyl groups with 1-6 carbon atoms, a is 0-250, b is 1-250, and c is 0-250; and
(B) a mono-alkenyl polyether of the formula CH2 ═
CH(CH2)x O(CH2 CH2 O)y (CH2 CH3 CHO)z T, or the formula CH2 ═
CH-Q-O(CH2 CH2 O)y (CH2 CH3 CHO)z T, where T is hydrogen, a C1 -C10 alkyl group, an aryl group, or a C1 -C20 acyl group;
Q is a divalent linking group containing unsaturation;
x is 1-6, y is zero or 1-100; and
z is zero or 1-100;
provided y and z are both not zero;
in the presence of a platinum catalyst, until an .tbd.Si--H containing polysiloxane with polyether groups is formed; and
reacting;
(C) the .tbd.Si--H containing polysiloxane with polyether groups;
(D) an unsaturated hydrocarbon selected from the group consisting of alpha, omega-dienes of the formula CH2 ═
CH(CH2)x CH═
CH2, alpha, omega-diynes of the formula CH.tbd.C(CH2)x C.tbd.CH, and alpha, omega-ene-ynes of the formula CH2 ═
CH(CH2)x C.tbd.CH, where x is 1-20;
in the presence of(E) a solvent selected from the group consisting of (i) organic compounds, (ii) compounds containing a silicon atom, (iii) mixtures of organic compounds, (iv) mixtures of compounds containing a silicon atom, and (v) mixtures of organic compounds and compounds containing a silicon atom; and
in the presence of a platinum catalyst, until a silicone elastomer is formed by crosslinking and addition of .tbd.SiH across double or triple bonds in the unsaturated hydrocarbon.
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Accused Products
Abstract
Low molecular weight siloxane fluids are thickened by silicone elastomers. The silicone elastomers are made by crosslinking reactions of .tbd.Si--H containing siloxanes and an unsaturated hydrocarbon such as an alpha, omega-diene, in the presence of a low molecular weight siloxane fluid. The .tbd.SiH siloxane is first partially reacted with a mono-alkenyl functionalized polyether. It is then crosslinked by the alpha, omega-diene, in the presence of the low molecular weight siloxane fluid. An elastomer, i.e. gel, with polyether groups is produced. The elastomer can be swollen with the low molecular weight siloxane fluid under shear force, to provide a uniform silicone paste. The silicone paste has excellent spreadability upon rubbing, and possesses unique rheological properties in being thixotropic and shear thinning. The silicone paste can be easily emulsified with water to form a stable uniform emulsion, without using a surfactant to allow normally immiscible materials to become intimately mixed.
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Citations
18 Claims
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1. A method of making a silicone elastomer comprising reacting:
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(A) an .tbd.Si--H containing polysiloxane of the formula R3 SiO(R'"'"'2 SiO)a (R"HSiO)b SiR3 or the formula (R'"'"'2 SiO)a (R"HSiO)b, and optionally an .tbd.Si--H containing polysiloxane of the formula HR2 SiO(R'"'"'2 SiO)c SiR2 H or an .tbd.Si--H containing polysiloxane of the formula HR2 SiO(R'"'"'2 SiO)a (R"HSiO)b SiR2 H, where R, R'"'"', and R" are alkyl groups with 1-6 carbon atoms, a is 0-250, b is 1-250, and c is 0-250; and (B) a mono-alkenyl polyether of the formula CH2 ═
CH(CH2)x O(CH2 CH2 O)y (CH2 CH3 CHO)z T, or the formula CH2 ═
CH-Q-O(CH2 CH2 O)y (CH2 CH3 CHO)z T, where T is hydrogen, a C1 -C10 alkyl group, an aryl group, or a C1 -C20 acyl group;
Q is a divalent linking group containing unsaturation;
x is 1-6, y is zero or 1-100; and
z is zero or 1-100;
provided y and z are both not zero;
in the presence of a platinum catalyst, until an .tbd.Si--H containing polysiloxane with polyether groups is formed; and
reacting;(C) the .tbd.Si--H containing polysiloxane with polyether groups; (D) an unsaturated hydrocarbon selected from the group consisting of alpha, omega-dienes of the formula CH2 ═
CH(CH2)x CH═
CH2, alpha, omega-diynes of the formula CH.tbd.C(CH2)x C.tbd.CH, and alpha, omega-ene-ynes of the formula CH2 ═
CH(CH2)x C.tbd.CH, where x is 1-20;
in the presence of(E) a solvent selected from the group consisting of (i) organic compounds, (ii) compounds containing a silicon atom, (iii) mixtures of organic compounds, (iv) mixtures of compounds containing a silicon atom, and (v) mixtures of organic compounds and compounds containing a silicon atom; and
in the presence of a platinum catalyst, until a silicone elastomer is formed by crosslinking and addition of .tbd.SiH across double or triple bonds in the unsaturated hydrocarbon. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18)
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Specification