Study of the simultaneous effects of MMT nanoclay and hydrophobically modified ethoxylated urethane (HEUR) on viscoelastic and steady shear properties of water-based acrylic resins

The storage stability of montmorillonite/acrylic resin was studied via rheological characterizations. The Na⁺–MMT nanoclay and a water-based acrylic resin were used for the preparation of different suspension samples. The effect of an associative polymer such as hydrophobically modified ethoxylated urethane (HEUR) in the mixture was also investigated. The result showed that the existence of an associative polymer has an influence on the stability and zero-shear viscosity of the system. In order to determine the behavior of this system under long-term storage, various rheological characterizations such as frequency sweep and rate sweep measurements were carried out. The results showed that adding the montmorillonite nanoclay and HEUR to the acrylic resin causes short- and long-term stabilities of suspensions microstructure. The required stability, a better flow, and a better structure were achieved, respectively, upon addition of an associative polymer, addition of MMT–Na⁺, and flow cessation.