High solids polycarboxylate synthesis for cement superplasticizers
(22) 18.11.2016
(43) 10.10.2018
(57) Summary of the corresponding patent WO2017095657 (A1): The present invention provides efficient methods to form a high solids content polymeric polyacid or a comb polymer useful as a superplasticizer or dispersant which comprise heating to from 80 to 100°C for a first time period, and then, sequentially, heating to a second temperature of from 150 to 250°C for a second time period a wet reaction mixture having a solids content of from 80 to 99 wt.% and comprising from 15 to 60 wt.% of one or more ethylenically unsaturated acid or a salt thereof, from 37 to 76.99 wt.% of one or more polyether polyols, alkyl polyether polyols, polyether amines or alkyl polyether amines in the presence of (i) from 0.01 to 1 wt.%, of one or more water soluble radical initiators or redox pairs and (ii) from 2 to 22 wt.% of one or more phosphorus oxide containing compounds, all weights based on the total weight of the wet reaction mixture.
(71) Rohm and Haas Company (US)