Thickening of low molecular weight siloxanes with acrylate/methacrylate polyether grafted silicone elastomers
First Claim
1. A method of making a silicone elastomer comprising as a first step, 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)d (R"HSiO)e, 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, c is 0-250, d is 0-10, and e is 3-10; and
(B) a monoacrylate functionalized polyether of the formula CH2 ═
CHCOO[CH2 CH2 O]m [CH2 CH(CH3)O]n [CH2 CH(CH2 CH3)O]p T, or a monomethacrylate functionalized polyether of the formula CH2 ═
C(CH3)COO[CH2 CH2 O]m [CH2 CH(CH3)O]n [CH2 CH(CH2 CH3)O]p T, where T represents hydrogen;
a C1-C30 linear or branched chain alkyl group, an aryl group, or a C1-C20 acyl group; and
m, n, and p, each represent integers which can be equal to zero or have values of 1-100;
in the presence of a platinum catalyst, until a polysiloxane is formed containing polyether substituents and residual silicon hydride groups;
and as a second step, reacting components comprising;
(C) the polysiloxane containing polyether substituents and residual silicon hydride 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, or an unsaturated siloxane monomer or siloxane polymer containing two or more terminal alkenyl groups;
two or more pendant alkenyl groups;
or two or more terminal and pendant groups;
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.
1 Assignment
0 Petitions
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 either a monoacrylate functionalized polyether or a monomethacrylate 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 gel 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 Theological 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.
30 Citations
18 Claims
-
1. A method of making a silicone elastomer comprising as a first step, 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)d (R"HSiO)e, 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, c is 0-250, d is 0-10, and e is 3-10; and (B) a monoacrylate functionalized polyether of the formula CH2 ═
CHCOO[CH2 CH2 O]m [CH2 CH(CH3)O]n [CH2 CH(CH2 CH3)O]p T, or a monomethacrylate functionalized polyether of the formula CH2 ═
C(CH3)COO[CH2 CH2 O]m [CH2 CH(CH3)O]n [CH2 CH(CH2 CH3)O]p T, where T represents hydrogen;
a C1-C30 linear or branched chain alkyl group, an aryl group, or a C1-C20 acyl group; and
m, n, and p, each represent integers which can be equal to zero or have values of 1-100;
in the presence of a platinum catalyst, until a polysiloxane is formed containing polyether substituents and residual silicon hydride groups;and as a second step, reacting components comprising; (C) the polysiloxane containing polyether substituents and residual silicon hydride 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, or an unsaturated siloxane monomer or siloxane polymer containing two or more terminal alkenyl groups;
two or more pendant alkenyl groups;
or two or more terminal and pendant groups;
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. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18)
-
Specification