Urea → Dipropylene glycol monocarbamate

810 parts of a polyethylene ether-diol of molecular weight 810 (H(OCH2CH2)18OH) and 60 parts of urea are heated in a stirred apparatus for 5 hours at 150° C., whilst passing a stream of nitrogen through the apparatus. After this time, the degree of conversion is 92%. Thereafter, 2,680 parts of dipropylene glycol, 1,200 parts of urea and 100 parts of the nickel-containing exchanger prepared as described in Example 1(a) are added. The reaction mixture is heated for 16 hours at 155° C., whilst passing a stream of nitrogen through the apparatus. After the mixture has cooled to about 100° C., the catalyst is filtered off. 4,350 parts of the co-carbamate mixture, consisting of 24% of a polyethylene ether-diol monocarbamate H(OCH2CH)18OCONH2 and 76% of dipropylene glycol monocarbamate, are obtained.