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Since their invention in 1981, polycarboxylate ether (PCE) polymers have attained a considerable share of the concrete superplasticizer market.This article reviews the state of art in PCE technology with respect to the chemistry being used, new promising applications and future challenges.Recently, in addition to the well-known methacrylate ester (MPEG), allyl and vinyl ether (APEG/VPEG) types, new PCEs based on copolymers from isoprenol ether and acrylic acid (IPEG-type) with excellent dispersing performance were introduced.Also, organo-silane modified, hyperbranched and crosslinked PCEs were presented as new concepts.Major challenges for current PCE technology include their high sensitivity to different cement compositions and consumption by clay impurities.Initial results indicate that new compositions can help to reduce this sensitivity, and that PCEs with hydroxyalkyl side chains exhibit are more robust against clay.A highly promising new development is the application of PCEs as cement additive which can help to increase efficiency of the clinker mill and to produce a cement with reduced water demand.