Recovering Fibres and Fillers

摘要

1,179,493. Polyurethanes and epoxy resins from polyethers and polyamines. FARBENFABRIKEN BAYER A.G. 28 April, 1967 [30 April, 1966], No. 19654/67. Headings C3B and C3R. [Also in Division D2] A flotation agent of a molecular weight of at least 2000 is obtained by reacting a polyfunctional derivative of a polyol with an amine that has at least two reactive amino groups. Either the amine or the polyol or both contains at least one ether group. The polyol may be ethylene glycol, glycerol, trimethylolpropane, hexanetriol, pentaerythritol, sorbitol, a reaction product of an alkylene oxide with a polyol or with another compound containing active hydrogen atoms, e.g. a primary amine or a polycarboxylic acid. Derivatives that may be used are esters of hydrohalic, alkyl- or aryl-sulphonic or chloroformic acids, partial esters of sulphuric acid, and derivatives that contain epoxy or chlorohydrin groups. Amines that can be used are of the formulµ and where R 1 is an organic radical, R 2 is hydrogen, an alkyl-, hydroxyalkyl., cyanoalkyl- or carbamidoalkyl group, R1 1 and R1 2 independently . are hydrogen or a substituent, in particular alkyl, cyanoalkyl, carbamidoalkyl, hydroxyalkyl, or polyalkylene oxide, X is oxygen, sulphur, or a radical having a valency of at least two and derived from an aliphatic, cycloaliphatic, aromatic or heterocyclic hydroxyl or sulphohydryl compound, R 3 is hydrogen or methyl, p and q are integers, and y is the valency of the radical X. Other amines that can be used are N,N1-bis-(3-aminopropyl)-hexamethylenediamine, dipropylene-(1,2)-triamine, tri - propylene -(1,2)-tetramine, piperazine, N - aminoethyl-piperazine and N,N1-bis-(3-aminopropyl)-piperazine. The flotation agent may contain reactive groups of one or both reagents. The reagents may be reacted together in a diluent, e.g. water, and the reaction interrupted by acidification.