Polymer-Modified Cementitious Coating Containing Calcium Stearate as a Multifunctional Coating

Polymer cementitious coatings (PCCs) are among the well-known types of coatings that combine organic and inorganic coating advantages. Crack-bridging, breathability, scratch resistance, and low water absorption are the main attained mechanical and durable properties of cementitious coatings due to polymer modification. In this research, the effect of calcium stearate (CS) in PCC was investigated. For this purpose, in the first step, PCCs with different polymer-to-cement ratios (P/Cs) (up to 0.6) were manufactured to obtain the optimum ratio. Results exhibited that a 40% P/C ratio enhances the pull-off strength compared to the others. Then, various CS (2.5%, 5%, and 10%) of the cement weight was added to the selected PCC mix proportion (P/C=0.4) to assess new characteristics of novel multifunctional PCC. The mini-slump flow diameter test, pull-off strength, capillary water absorption, contact angle, microstructure, and rapid chloride migration test have been studied. The outcomes illustrated that adding 2.5% CS can improve the permeability and durability of PCC under capillary condition with the lowest negative effect on bond strength and flowability.