Preparation of water-soluble condensates and their use as crosslinking agents for the preparation of papermaking aids
Abstract
Abstract A process for the preparation of water-soluble polymeric crosslinking agents by a two-stage reaction of di-secondary diamines with epichlorohydrin and/or dichlorohydrin, wherein, in the first stage, di-secondary diamines are condensed with epichlorohydrin and/or dichlorohydrin in a molar ratio of from 1:0.5 to 1:1 at a pH of from 9 to 12, and in the second stage the condensates obtained in the first stage are reacted with additional epichlorohydrin and/or dichlorohydrin at a pH of from 4 to 8.5. The water-soluble condensates thus obtained are crosslinking agents for polyamines, polyamidoamines, ethyleneimine-modified polyamidoamines and polyether-amines. The crosslinking reaction gives water-soluble condensates, which possess a high cation activity and may be used as retention aids, drainage aids and flocculants in the manufacture of paper.
Inventors
- 👤 Otto Hertel
- 👤 Emil Scharf
- 👤 Jaroslav Melzer
Bibliographic Details
Claims Analysis
Total Claims: 4References Cited (Backward Citations)
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