Patent GB-643456-A (GB)
Title: Improvements in or relating to surface active ingredients
IPC: A01N31/02
Filed: 1946-11-13
Abstract: Polyethylene glycol thioethers are prepared by condensing ethylene oxide with a tertiary alkyl mercaptan derived from a polymerized olefine and having 8 to 24 carbon atoms in the tertiary alkyl radical, the ethylene oxide being condensed with the mercaptan in a stoichiometric ratio of between 2 : 1 and 28 : 1.  Mixtures of mercaptans may be used.  Condensation may be effected by bubbling the ethylene oxide through the mercaptan to which is added a basic catalyst such as an alkali metal base, basic salt or alcoholate. This catalyst may be added to the mercaptan which is then heated under reduced pressure whereby a solution of the corresponding alkali metal &c. mercaptide in excess mercaptan is formed for reaction with the ethylene oxide. Condensation may be effected at atmospheric or raised pressures with heating.  The thioethers are solids or liquids having surface active properties (see Group IV (c)).  In examples: (1) octa- and dodecaethylene glycol t-dodecyl thioethers are prepared by heating the parent mercaptan with sodium methylate under reduced pressure and then reacting the product with the appropriate amount of ethylene oxide under raised pressure; a polyethylene glycol t-hexadecyl thioether containing 14.87 ethylene oxide units may be prepared similarly from t-hexadecyl mercaptan; (2) a series of thioethers are prepared as in (1) from t-octyl, t-dodecyl and t-tetradecyl mercaptans, the ethylene oxide being introduced discontinuously and samples withdrawn at each stage yielding products containing from 2 to 26 ethylene oxide units in the p  molecule; (3) another series of products is similarly obtained from t-dodecyl mercaptan, condensation being effected at atmospheric pressure. Other mercaptans specified are those derived from the dimer, trimer and tetramer of pentene-2, the trimer, tetramer, pentamer and hexamer of propylene and copolymers of mixtures of these olefines.  The preparation of the mercaptans is described (see Group IV (b)). Specification 437,590 is referred to.  The Specification as open to inspection under Sect. 91 includes the use of mercaptans obtained by reacting terpenes with hydrogen sulphide.  This subject-matter does not appear in the Specification as accepted.ALSO:Polyethylene glycol thioethers are prepared by condensing ethylene oxide with a tertiary alkyl mercaptan derived from a polymerized olefine and having from 8 to 24 carbon atoms in the tertiary alkyl radical, the ethylene oxide being condensed with the mercaptan in a stoichiometric ratio of between 2 : 1 and 28 : 1.  Mixtures of mercaptans may be employed. The condensation may be effected by bubbling the ethylene oxide through the mercaptan to which is added a basic catalyst such as an alkali metal base, basic salt or alcoholate.  This catalyst may be added to the mercaptan which is then heated under reduced pressure whereby a solution of the corresponding alkali metal mercaptide is formed for reaction with the ethylene oxide.  The condensation may be effected at atmospheric or raised pressures.  The product is worked up by treatment with acid-activated clay which removes the catalyst and improves colour and odour or the catalyst may be neutralized by acetic acid and the product treated with charcoal and heated under reduced pressure.  The thioethers are liquids and solids and are wetting agents and detergents (see Group IV (c)). In examples: (1) dodeca-and octa-ethylene glycol t-dodecyl thioethers are prepared by heating the parent mercaptan (prepared by condensing hydrogen sulphide with tri-isobutylene) with sodium methylate under reduced pressure and then heating the product under raised pressure while introducing the appropriate quantity of ethylene oxide; in like manner, a polyethylene glycol t-hexadecyl thioether containing 14.87 ethylene oxide units is prepared from t-hexadecyl mercaptan (obtained by condensing hydrogen sulphide with tetraisobutylene); (2) a series of thioethers are prepared as in (1) from t-octyl, t-dodecyl and t-tetradecyl mercaptans (obtained from hydrogen sulphide and di- and tri-isobutylene and dimerized heptene respectively), the ethylene oxide being introduced discontinuously and samples withdrawn at each stage, thus yielding a series of products containing from 2 to 26 ethylene oxide units in the molecular; (3) another series of like products is obtained from the t-dodecyl mercaptan, the condensation being effected at atmospheric pressure.  The mercaptans may be prepared, for example, by the method described in U.S.A. Specification 2,378,030.  Other mercaptans specified are those derived from the dimer, trimer or tetramer of pentene-2, the trimer, tetramer, pentamer or hexamer of propylene or copolymers of mixtures of these olefines. Specification 437,590 is referred to.  The Specification as open to inspection under Sect. 91 includes the use of mercaptans obtained by reacting terpenes with hydrogen sulphide. This subject-matter does not appear in the Specification as accepted.ALSO:Surface-active agents are prepared by reacting ethylene oxide with a tertiary alkyl mercaptan derived from a polymerized olefine and having 8 to 24 carbon atoms in the tertiary alkyl group, the ethylene oxide being condensed with the mercaptan in a stoichiometric ratio of between 2 : 1 and 28 : 1 (see Group IV (b)). The resulting polyethylene glycol thioethers are useful as wetting agents and detergents and with water may be used in the washing of fibrous materials.  Specified products are those prepared from the mercaptans derived from the dimers, trimers and tetramers of isobutylene and pentene-2, the trimer, tetramer, pentamer and hexamer of propylene and co-polymers of mixtures of these olefines. Specification 437,590 is referred to.  The Specification as open to inspection under Sect. 91 refers also to the thioethers obtained from mercaptans prepared by reacting hydrogen sulphide with terpenes. This subject-matter does not appear in the Specification as accepted.