Abstract: A process for the preparation of polycarbonate copolyether diols comprising two successive reaction stages wherein in the first stage the precursor, bisdimethylcarbonate of polyether diols is synthesized by reacting, in a reactor equipped with a distillation column, one or more polyetherglycols with dimethyl carbonate, in the presence of a basic catalyst selected from the group consisting of an oxide, a hydroxide, a carbonate and an alcoholate of a metal belonging to the group of alkaline or earth-alkaline metals and in the second stage, the precursor, after being freed from the catalyst and excess dimethylcarbonate, is converted to polycarbonate copolyether diols by transesterification reaction with polyetherglycols in the presence of a solvent and an organometallic catalyst selected from compounds of tin, lead, titanium, zirconium and antimonium, said polycarbonate polyether diols having utility as additives in the field of polyurethane end-products, thermoelastomers, paints and adhesives.

Abstract: Uses of topical compositions comprising a 2-hydroxycarboxylic acid or related compound to alleviate or improve signs of skin, nail and hair changes associated with intrinsic or extrinsic aging are disclosed. 2-Hydroxycarboxylic acids and their related compounds include, for example, 2-hydroxyethanoic acid, 2-hydroxypropanoic acid, 2-methyl 2-hydroxypropanoic acid, 2-phenyl 2-hydroxyethanoic acid, 2-phenyl 2-methyl 2-hydroxyethanoic acid, 2-phenyl 3-hydroxypropanoic acid, 2,2-diphenyl 2-hydroxyethanoic acid, 2-hydroxybutane-1,4-dioic acid, 2,3-hihydroxybutane-1,4-dioic acid, 2-carboxy 2-hydroxypentane-1,5-dioic acid, 2-ketopropanoic acid, methyl 2-ketopropanoate, ethyl 2-ketopropanoate, and gluconolactone.

Abstract: A polycarbonate is produced by transesterification from a dihydroxy compound such as 2,2-bis(4-hydroxyphenyl)propane and a diester of carbonic acid such as bisphenyl carbonate in the presence of a substance which contains iron in an amount of 50% by weight or less and contacts the reactants. Alternatively, a polycarbonate is produced by transesterification from a dihydroxy compound and a diester of carbonic acid in a reactor made of stainless steel and treated by electropolishing or acid pickling or buffed on a surface part thereof which contacts the reactants. As the transesterification catalyst, (a) a nitrogen-containing, electron-donating compound and (b) a nitrogen-containing, electron-donating compound and an alkali metal compound or an alkaline earth metal compound are preferably used.