| 摘要 |
The invention relates to a process for the preparation of polymers containing pendant polyalkylene oxide chains, in which polyalkylene oxides containing at least two free hydroxyl groups on the starting alcohol which are separated from one another by at most three carbon atoms and where the hydroxyl group at the far end of the polyalkylene oxide chain is blocked, optionally reversibly, are reacted with difunctional compounds which are reactive with respect to the hydroxyl groups on the starting alcohol, optionally in the presence of solvents and/or catalysts and/or at elevated temperatures, where the reaction is carried out in at least two steps by reacting, in the first step, the polyalkylene oxide diols with the reactive difunctional compounds in a molar ratio of from 1: > 1 to 1 : 2, and, in a second step, reacting the resultant intermediate with polyalkylene oxide diol in a molar ratio of from 1 : 2 to 2 : 1, and optionally repeating steps 1 and/or 2 with this process product until the desired molecular weight has been achieved. The two-step process according to the invention is superior to the one-step process with respect to the yield. The polymers obtained have approximately the molecular weight determined by calculation. The process according to the invention enables the preparation of polymers containing different polyalkylene oxide side chains, which can be alternating or in the form of blocks. The compounds have surfactant properties.
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