Patent GB-899825-A (GB)
Title: Surface-active acetals and formals
Filed: 1958-09-23
Abstract: Oil-water emulsions containing as emulsifying agent a water- and oil-soluble compound of the general formula <FORM:0899825/III/1> are modified by decomposing said emulsifying agent under acidic conditions.  In the above formula R is a hydrogen atom or an alkyl group, R1 is an alkyl group, R and R1 together having a total of 8 to 24 carbon atoms, R2 is a hydrogen atom or a methyl group, Z is a hydrocarbon group containing at least 8 carbon atoms and which is such as to yield a water-soluble fragment H(OCH2CH2)nOZ on acidification of said compound, A is an oxygen or sulphur atom and n is an integer from 6 to about 50, or a mixture of such compounds containing different numbers of ethenoxy groups the average value of n being from 6 to about 50.  The emulsifier may be decomposed by treatment with dilute acid at an elevated temperature when the surface activity is transferred from the oil phase to the water phase.  Preferred values for Z are alkyl, alkenyl and alkylphenyl containing at least 8 carbon atoms.ALSO:The invention comprises compounds of the general formula <FORM:0899825/IV (a)/1> where R is a hydrogen atom or an alkyl group, R1 is an alkyl group, R and R1 together having a total of 8 to 24 carbon atoms, R2 is a hydrogen atom or a methyl group, Z is an hydrocarbon group having at least 8 carbon atoms and which is such as to yield a water-soluble fragment H(OCH2CH2)nOZ on acidification of said compound. A is oxygen or sulphur and n is an integer from 6 to about 50 and mixtures of such compounds containing different numbers of ethenoxy groups, the average value of n being from 6 to about 50. The compounds may be prepared by reacting a compound of the formula <FORM:0899825/IV (a)/2> p  where X is chlorine or bromine, with an alcohol of the formula H(OCH2CH2)nOZ in the presence of a strongly basic inorganic neutralizing agent, for example potassium hydroxide, at about 50 DEG to 70 DEG C.  Alternatively, when an acetal is desired, i.e. R2 is a methyl group, a vinyl ether of the formula <FORM:0899825/IV (a)/3> may be reacted with an alcohol H(OCH2CH2)nOZ in the presence of an acid such as hydrochloric or phosphoric acid, boron trifluoride or its co-ordination complexes.  Many reactants for both methods are listed and examples are given.  Oil-water emulsions containing the novel compounds as emulsifier may be modified on acidification of the emulsion when a water-soluble surface-active fragment H(OCH2CH2)nOZ is obtained.ALSO:The invention comprises compounds of the general formula <FORM:0899825/IV (b)/1> where R is a hydrogen atom or an alkyl group, R1 is an alkyl group, R and R1 together having a total of 8 to 24 carbon atoms, R2 is a hydrogen atom or a methyl group, Z is a hydrocarbon group having at least 8 carbon atoms, and which is such as to yield a water-soluble fragment H(OCH2CH2)nOZ on acidification of said compound, A is oxygen or sulphur and n is an integer from 6 to about 50 and mixtures of such compounds containing different numbers of ethenoxy groups, the average value of n being from 6 to about 50. The compounds may be prepared by reacting a compound of the formula <FORM:0899825/IV (b)/2> where X is chlorine or bromine, with an alcohol of the formula H(OCH2CH2)nOZ in the presence of a strongly basic inorganic neutralizing agent, for example potassium hydroxide, at about 50 DEG C. to 70 DEG C. Alternatively, when an acetal is desired, i.e. R2 is a methyl group, a vinyl ether of the formula <FORM:0899825/IV (b)/3> may be reacted with an alcohol H(OCH2CH2)nOZ in the presence of an acid such as hydrochloric or phosphoric acid, boron trifluoride or its coordination complexes.  Many reactants for both methods are listed and examples are given.  Oil-water emulsions containing the novel compounds as emulsifier may be modified on acidification of the emulsion, when a water-soluble surface-active fragment H(OCH2CH2)nOZ is obtained.