Abstract A thermoresponsive copolymer solution is used to control the mechanical properties of a cement paste suspension. We use a comb copolymer consisting of a polymethacrylic acid (PMAA) backbone grafted with a polypropylene oxide (PPO) and polyethylene oxide (PEO) copolymer that possesses a low critical solution temperature (LCST). When the temperature crosses the LCST value, microphase separation occurs and the adsorption of the copolymer onto the cement particles is modified. We show that a control of the grafting ratio and of the graft chain composition allows monitoring of the transition temperature as well as the viscosity of the paste in the low and high temperature phases.