| 摘要 |
A polymer containing monomer units of acrylamide and/or methacrylamide, for example polyacrylamide, a secondary amine, for example dimethylamine, and, as stabiliser, a nitrogen-containing functional acid derivative which is capable of undergoing an equilibrium reaction with formaldehyde at the hydrogen-carrying nitrogen in the functional group, for example urea, are chemically linked to one another by means of formaldehyde, which reacts with hydrogen-carrying N atoms of its coreactants. For the reaction, which is carried out under basic conditions, the amounts of said starting materials are matched to one another in a particular way. The process enables polyamidoamine compounds to be obtained which have a good shelf life in aqueous medium and can be used as flocculants for aqueous colloidal solutions or suspensions. Particular mention should be made of the use as dewatering and filler retention agents in papermaking, for example also in the presence of aluminium sulphate.
|
