Patent GB-1088493-A (GB)
Title: Siloxane-alcohol ethers
IPC: B01D19/04
Filed: 1964-08-26
Abstract: Anti-foaming agents for aqueous dispersions of hydrocarbon liquids comprise hydroxy hydrocarbyloxyalkylsiloxanes wherein the hydrocarbyloxy group is further substituted by an hydroxy, alkenyloxy or organosilicon substituted a koxy group, and wherein the alkyl group contains at least two successive carbon atoms and any remaining valencies of silicon are attached to a monovalent hydrocarbon group (see Division C3).  Specified hydrocarbons are fuels (e.g. kerosene, gasoline, diesel fuels and mixtures thereof with aromatic hydrocarbons), paraffinic and naphthenic lubricating oils, aliphatic and cycloaliphatic hydrocarbons, mineral oils, and mixtures thereof with aromatic hydrocarbons. The hydrocarbons may also contain additives such as hydrocarbyl sulphates and sulphonates, alkali metal salts of these, kerosene, and tetraethyl lead.  The siloxanes may be used in a solution of an ether, hydrocarbon or haloalkane, or in a solid or molten state. Examples 16 and 17 describe the anti-foaming effect of various siloxanes of the invention on a lube-oil and a crude-oil respectively.  Example 21 describes the preparation of a wax composition suitable for coating painted metals, by heating a mixture comprising a siloxane of formula <FORM:1088493/C4-C5/1> a trimethylsiloxy end-blocked dimethylpolysiloxane, Carnauba wax, petroleum wax, silica powder, refined diatomaceous earth, turpentine and mineral spirits.  The wax formed was applied with cheese cloth to a metal panel coated with acrylic paint.ALSO:Siloxanes having at least one hydrocarbyloxy group linked to a silicon atom via at least two consecutive carbon atoms of an alkylene group, one of said carbon atoms being linked to silicon, the hydrocarbyloxy group having at least two substituents, one of which is a hydroxyl group and the other of which is a hydroxyl, alkenyloxy or organosilicon substituted alkoxy group, any remaining valencies of silicon being satisfied by hydrogen or monovalent hydrocarbyl groups free from aliphatic unsaturation, are prepared by reacting, in the presence of a platinum catalyst, a siloxane containing silanic hydrogen and monovalent hydrocarbyl groups free from aliphatic unsaturation, with a hydrocarbyloxy alkene having at least two substituents, as defined above, on the hydrocarbyloxy group. Specified siloxanes comprise units of formulae (1), (2) or (3) <FORM:1088493/C3/1> <FORM:1088493/C3/2> <FORM:1088493/C3/3> and optionally units of formula <FORM:1088493/C3/4> wherein R is hydrogen or an alkenyl group n is 2 to 10, a is at least 2, R1 is a monovalent hydrocarbon group free from aliphatic unsaturation, x is 0 to 2, Z is hydrogen or as R1 and z is 0 to 3. The hydroxy groups of the siloxanes may be modified, e.g. by reaction with isocyanates giving urethanes; polycarboxylic acids and anhydrides giving polyesters and sulphamic acid giving the corresponding quaternary ammonium sulphate; the alkenyl group may also be modified, e.g. by epoxidization, or by reaction with a siloxane containing the group <FORM:1088493/C3/5> to yield siloxanes containing units of the formula <FORM:1088493/C3/6> A typical Example, (1), describes the preparation of <FORM:1088493/C3/7> but other examples are given.  Examples (11)-(14) describe the modification of these siloxanes with o-tolylisocyanate, sulphamic acid, maleic anhydride and epichlorohydrin respectively, the chloride produced in (14) then being quaternerized with trimethylamine. Polyurethane foams may be prepared by reacting (a) a siloxane defined above, (b) an organic compound containing at least 2 alcoholic hydroxy groups, (c) an organic polyisocyanate, (d), a catalyst, and (e) a blowing agent.  The organic polyhydroxy compound may be a hydroxyl-ended polyether, polyester, polyamide, or polyamine; many polyethers are specified.  Many suitable isocyanates, blowing agents and catalysts are also specified.  The foams may also comprise additives, e.g. diol foaming modifiers, cross-linking agents, flame retardants, thermal stabilizers, plasticizers, fillers, pigments, dyes, antioxidants, antiozonates, deodorants and fungicides; suitable additives are specified.  The examples describe the preparation of foams from (20) propylene oxide / sorbitol / water adduct, tolylenediisocyanate, trichlorofluoromethane, dibutyl tin dilaurate and the siloxane of Example (1); and (21) propylene oxide/glycerol adduct, tolylene diisocyanate, water, tetramethylbutanediamine, N - ethylmorpholine, stannous octoate and various siloxanes.  The siloxanes may also be used as antifoaming agents for aqueous dispersions of, inter alia, polymerized olefines.  Example 18 describes the antifoaming effect of various siloxanes on an aqueous butadiene/styrene copolymer latex.ALSO:Anti-foaming agents for aqueous dispersions of hydrocarbon liquids comprise hydroxy hydrocarbyloxyalkysiloxanes wherein the hydrocarbyloxy group is further substituted by a hydroxy, alkenyloxy or organosilicon substituted alkoxy group, and wherein the alkyl group contains at least two successive carbon atoms and any remaining valencies of silicon are attached to a monovalent hydrocarbon group, (see Division C3).  Specified hydrocarbons are fuels (e.g. kerosene, gasoline, diesel fuels and mixtures thereof with aromatic hydrocarbons), paraffic and naphthenic lubricating oils, aliphatic and cycloaliphatic hydrocarbons, mineral oils, and mixtures thereof with aromatic hydrocarbons.  The hydrocarbons may also contain additives such as hydrocarbyl sulphates and sulphonates, alkali metal salts of these, kerosene, and tetraethyl lead.  The siloxanes may be used in a solution of an ether, hydrocarbon or haloalkane, or in a solid or molten state.  Examples 16 and 17 describe the antifoaming effect of various siloxanes of the invention on a lube-oil and a crude-oil respectively.