摘要 |
Beta-hydroxyl polysulphoniums are prepared from polymers having epoxy groups in the polymeric chain or on the side chains. The polymer is treated with one or more mercaptans or thiols in the presence of a catalyst which opens the oxirane bridges, in particular a basic catalyst, after which the remaining epoxy groups are eliminated by the action of an acid; the resultant polysulphide is then reacted with an alkyl halide or ester in the absence of acid in order to form the polysulphonium. Purification of the product is then carried out. The products can be obtained in this manner in a form which is soluble or dispersible in water in a suitable state of purity, with good yields and with the desired hydrophilic-lipophilic ratio.
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