GB971173A - New polyethers - Google Patents

Abstract

The inventions comprises ketonic-ended polyethers of the general formula <FORM:0971173/C3/1> wherein X stands for a monovalent or polyvalent radical derived from a compound X(H)a in which a is the number of hydrogen atoms reactive with a cyclic oxide, R is hydrogen or hydrocarbon radical, R1 is a hydrocarbon radical, n is at least 1 and m is 0 or an integer. R and R1 may be straight or branched chain radicals which may be substituted by halogen. They are prepared by oxidising compounds of general formula <FORM:0971173/C3/2> in presence or absence of a solvent medium. They may also be prepared by reaction of methyl vinyl ketone with a hydroxyl ended polyether in presence of a basic catalyst. Oxidising agents used include chromic acid, aluminium isopropoxide in presence of acetone, N bromosuccinimide, N-bromoacetamide, nitric acid and chromium trioxide in pyridine. Any temperature may be used but with chromic acid temperatures below 5 DEG C. are preferred. The radical X may be derived from compounds containing one or more hydroxyl, primary amino, secondary amino, carboxylic acid, carboxylic amide or mono-N-substituted carboxylic amide groups or a combination thereof. Suitable starting materials include linears polyethers prepared by (a) the polymerization of an alkylene oxide e.g. 1:2 propylene oxide, 1:2 butylene oxide 2:3 butylene oxide or epichlorohydrin in presence of a basic catalyst and a substance containing one or two hydrogen atoms, e.g. butanol, phenol, octanol, ethylene glycol or a primary amine, (b) polymerisation of an alkylene oxide in presence of a basic catalyst and a substance having more than two active hydrogen atoms per molecule, e.g. NH3, glycerol, hexane triols, trimethylol ethane, triethanol-amine, pentaerythritol, sucrose and phenol-aldehyde reaction products, monoethanolamine diethanolamines, ethylene diamine hexamethylene diamine, diethylene triamine, tolylene diamine and diaminodiphenylmethane and (c) reacting alkylene oxides with primary hydroxyl ended polymers which may be prepared by polymerizing an a :o unsubstituted cyclic oxide in presence of a compound containing one or more active hydrogen atoms and a catalyst. Suitable solvents include acetone, water, diethyl ketone, methyl ethyl ketone, acetic acid and propionic acid. In examples (1) Polypropylene glycol (MW.1025) in acetone is oxidised below 0 DEG C. using chromium trioxide and sulphuric acid. (2) Polyoxypropylene triol (MW.1500) in water is oxidised at 5 DEG C. using sodium dichromate and concentrated sulphuric acid. (3) Polyoxypropylene diol (MW.1000) in water is oxidised at below 3 DEG C. using chromium trioxide and concentrated sulphuric acid.