Abstract: Process for the production of glycidyl (meth)acrylate copolymers with a number-average molar mass (Mn) of 1000 to 6000 g/mol by solvent-free, continuous copolymerisation of glycidyl (meth)acrylate with ethylenically unsaturated monomers, in a reaction vessel with feed and discharge means in the presence of a polyester oligomer, wherein polyester oligomer or a mixture of glycidyl (meth)acrylate copolymer and polyester oligomer is initially introduced in a weight ratio of from 95:5 to 50:50 and the glycidyl (meth)acrylates, further monomers, further polyester oligomer and, optionally, free-radical initiators are added, the addition together with discharge of the copolymers formed being effected in such a way that the residence time required for formation of the desired composition is achieved, and wherein, in the event of the initial introduction of the mixture of glycidyl (meth)acrylate copolymer and polyester oligomer, addition is effected in such a way that the ratio between copolymer and oligomer is maintai

Abstract: 1,3-Butadiene is recovered with the aid of a selective solvent from a C.sub.4 -hydocarbon mixture containing 1,3-butadiene, hydrocarbons which are more soluble in said selective solvent than 1,3-butadiene, including acetylenes and possibly 1,2-butadiene and C.sub.5 -hydrocarbons, and hydrocarbons which are less soluble in said selective solvent than 1,3-butadiene. The C.sub.4 -hydrocarbon mixture is separated by the use of one or more extractive distilling zones into a distillate containing the less soluble hydrocarbons, a stream consisting of 1,3-butadiene and a stream containing the more soluble hydrocarbons including the higher acetylenes and 1,3-butadiene, the latter stream being subjected to catalytic hydrogenation.