摘要:
A process for isolating butadiene, with the aid of a selective solvent, from a C.sub.4 -hydrocarbon mixture which contains butadiene and small amounts of styrene and may contain oxygen, hydrocarbons more soluble than butadiene in the selective solvent and hydrocarbons less soluble than butadiene in the selective solvent, in which process the C.sub.4 -hydrocarbon mixture is separated by extractive distillation into a distillate which contains the less soluble hydrocarbons, a stream of butadiene and a stream containing the more soluble hydrocarbons, and in which a mixture of styrene and C.sub.4 -hydrocarbons is removed from the C.sub.4 -hydrocarbon mixture in a distillation zone upstream of the extractive distillation, the top product of the said distillation zone being fed to the extractive distillation.
摘要:
A process for isolating a conjugated diolefin from a C.sub.4 - or C.sub.5 -hydrocarbon mixture containing the diolefin, by single-stage or multi-stage extractive distillation using a selective solvent, wherein the selective solvent is a solvent mixture which comprises(a) from 1 to 99 percent by weight of an N-alkyl-substituted lower aliphatic acid amide or of an N-alkyl-substituted alicyclic acid amide having 5 ring members and(b) from 1 to 99 percent by weight of an aliphatic or alicyclic ether boiling at from 30.degree. C. to 200.degree. C.
摘要:
Polymeric materials (I) are obtainable by reacting1. a polymer II comprisinga) from 80 to almost 100 mol % of a C.sub.1 -C.sub.25 -alkyl ester of an .alpha.,.beta.-unsaturated carboxylic acid,b) from 0 to 20 mol % of a further monomer,c) tetrahydrofuran hydroperoxide as polymerization initiator and, if required,d) a further polymerization initiator and/or regulator by means of which the majority of the polymer chains of the polymer II are terminated at one of their ends by a hydroxyl group,2. with a polyfunctional isocyanate III to give a reaction product IV, the amount of isocyanate groups being from 1.2 to 3.0 mol per mol of hydroxyl groups of II, and3. reacting IV with ammonia or with a compound V which has an amino function reactive toward isocyanates.The polymeric materials can be used as dispersing resins for pigment-containing coatings, in particular for the production of magnetic recording materials.
摘要:
Radiation-curable urethane acrylate compounds containing amine and urea groups and based on di- or polyisocyanates, hydroxy compounds and amines contain secondary or tertiary amino groups which are bonded to isocyanate via hydroxyl groups and are obtainable by an addition reaction of primary or secondary amines with hydroxyacrylates.