Patent GB-873975-A (GB)
Title: Method for making foams
IPC: C08J9/14
Filed: 1957-11-22
Abstract: A process for the production of a polyurethane foam comprises mixing together (A) an alkyd resin comprised of (1) a polycarboxylic compound and (2) a polyhydric alcohol at least a portion of which contains at least three hydroxyl groups, (B) a polyisocyanate and (C) a foaming agent comprised of (1) a tertiary alcohol having the formula R1R2R3C-OH where R1 is an aliphatic group containing at least one hydrogen atom bonded to the carbon atom immediately adjacent to the carbinol group, and R2 and R3 are aliphatic or aromatic groups, and (2) a concentrated acid in an amount not exceeding 50% of the weight of the tertiary alcohol; foaming the mixture at an elevated temperature and curing the resulting product.  Alcohols specified are tertiary butyl and amyl alcohols, 2-ethyl-2-butanol, 2-ethyl-2-pentanol, 2-methyl-2-pentanol, 3-methyl-3-hexanol, 4-methyl- 4-heptanol, 4-propyl- 4-heptanol, 4-ethyl- 4-heptanol, 2, 3-dimethyl-3-butanol, 2, 3-dimethyl- 3-pentanol, 2, 3, 4-trimethyl- 3-pentanol, 3-ethyl-2, 4-dimethyl- 3-pentanol, 3-isopropyl-2, 4-dimethyl- 3-pentanol, terpinol; 2-methyl- 3-butyn-2-ol, 3-methyl- 1-1-pentyn- 3-ol, 3, 5-dimethyl- 1-hexyn- 3-ol, 2-methyl- 3-isopropyl- 4-pentyn-3-ol, 1-ethynyl- 1-cyclohexanol, 2-ethyl- 3-pentone- 2-ol, 2-methyl4-pentene- 2-ol, 4-methyl- 1-heptene- 4-ol, 2, 4-dimethyl- 3-isopropyl- 4-pentene- 2-ol, alphaterpinol; 1-methyl- 1-phenyl-ethanol, 1, 1-diphenylethanol, 1-methyl-1, 2, -diphenyl ethanol, 1, 2-dimethyl-1, 2-diphenylethanol, 2-methyl-1, 1, 2-triphenylethanol and 1, 1, 2, 2-tetraphenylethanol. Specific acids are sulphuric, phosphoric, nitric, polyphosphoric, chlorosulphonic, hydrochloric, p-toluene sulphonic, benzenesulphonic, naphthalene-sulphonic, picric, trichloracetic and trifluoro-acetic acids.  Lewis-type acids such as aluminium chloride, boron trifluoride and boron trichloride can also be used.  The alkyd can be derived from maleic, fumaric, itaconic, citraconic, aconitic, phthalic, tetrachlorophthalic, oxalic, malonic, succinic, glutaric, adipic, pimelic, suberic and azelaic acids.  To give a rigid foam the polyhydric alcohol must contain at least three hydroxyl groups as in glycerol, hexanetriol, butanetriol, trimethylolpropane, trimethylolethane and pentaerythritol.  Glycol or 1, 4-butanediol may replace part of this.  As polyisocyanates tolylene, naphthalene-1, 5-, bitolylene and 3, 31-dimethoxy-4, 41-biphenylene diisocyanate and methylene-bis(4-phenylisocyanate) are suitable.  Wetting agents can be added in the foaming.  Other additives are clay, calcium sulphate, ammonium phosphate, dyes, fibrous glass, asbestos, synthetic fibres, and a mixture of methyl pentachlorostearate and epoxidized soy bean oil.  In Examples (1) an adipic acid/phthalic anhydride/glycerol alkyd is foamed by addition successively, at elevated temperature of dioctyl sulphosuccinate in amyl alcohol and conc. sulphuric acid; (2) a prepolymer from a rather similar alkyd and toluene diisocyanates is foamed by adding t-amyl alcohol containing conc. sulphuric acid.ALSO:A process for the production of a polyurethane foam comprises mixing together (A) an alkyd resin comprised of (1) a polycarboxylic compound and (2) a polyhydric alcohol at least a portion of which contains at least three hydroxyl groups, (B) a polyisocyanate and (C) a foaming agent comprised of (1) a tertiary alcohol having the formula R1R2R3C-OH where R1 is an aliphatic group containg at least one hydrogen atom bonded to the carbon atom immediately adjacent to the carbinol group, and R2 and R3 are aliphatic or aromatic groups, and (2) a concentrated acid in an amount not exceeding 50% of the weight of the tertiary alcohol; foaming the mixture at an elevated temperature and curing the resulting product.  Alcohols specified are tertiary butyl and amyl alcohols, 2-ethylbutanol, 2-ethyl-2-pentanol, 2-methyl-2-pentanol, 3-methyl-3-hexanol, 4-methyl-4-heptanol, 4-propyl-4-heptanol, 4-ethyl-4-heptanol, 2, 3-dimethyl-3-butanol, 2, 3-dimethyl-3-pentanol, 2, 3, 4-trimethyl-3-pentanol, 3-ethyl-2, 4 - dimethyl - 3-pentanol, 3-isopropyl - 2, 4-dimethyl-3-pentanol, terpinol; 2-methyl-3-butyn-2-ol, 3-methyl-1-pentyn-3-ol, 3,5-dimethyl-1-hexyn-3-ol, 2-methyl-3-isopropyl-4-pentyn-3-ol, 1-ethynyl-1-cyclohexanol, 2-ethyl-3-pentone-2-ol, 2-methyl-4-pentene-2-ol, 4-methyl-1-heptene-4-ol, 2, 4-dimethyl-3-isopropyl-4-pentene-2-ol, alpha-terpinol; 1-methyl-1-phenyl-ethanol, 1, 1-diphenylethanol, 1-methyl-1, 2, -diphenylethanol, 1, 2-dimethyl-1, 2 - diphenylethanol, 2 - methyl - 1,1, 2 - triphenylethanol and 1, 1, 2, 2-tetraphenylethanol. Specific acids are sulphuric, phosphoric, nitric, polyphosphoric, chlorosulphonic, hydrochloric, p-toluene sulphonic, benzenesulphonic, naphthalene-sulphonic, picric, trichloracetic and trifluoro-acetic acids.  Lewis-type acids such as aluminium chloride, boron trifluoride and boron trichloride can also be used.  The alkyd can be derived from maleic, fumaric, itaconic, citraconic, aconitic, phthalic, tetrachlorophthalic oxalic, malonic, succinic, glutaric, adipic, pimelic, suberic and azelaic acids.  To give a rigid foam the polyhydric alcohol must contain at least three hydroxyl groups as in glycerol, hexanetriol, butanetriol, trimethylolpropane, trimethylolethane and pentaerythritol.  Glycol or 1-, 4-butandediol may replace part of this.  As polyisocyanates tolylene, napthalene-1, 5-, bitolylene and 3, 31-dimethoxy-4, 41-biphenylene diisocyanate and methylene-bis-(4-phenylisocyanate) are suitable.  Wetting agents can be added in the foaming.  Other additives are clay, calcium sulphate, ammonium phosphate, dyes, fibrous glass, asbestos, synthetic fibres, and a mixture of methyl pentachlorostearate and epoxidised soy bean oil.  In examples (1) and adipic acid/phthalic anhydride/glycerol alkyd in foamed by addition, successively, at elevated temperature, of dioctyl sulphosuccinate is amyl alcohol and conc. sulphuric acid; (2) a prepolymer from a rather similar alkyd and toluene diisocyanates is foamed by adding t-amyl alcohol containing conc. sulphuric acid.