The occurrence of calcium carbonate (CaCO3) efflorescence phenomenon is not new and is generally found in the form of unsightly white deposits on the surface of cement products. It appears just after completion of building construction and causes aesthetically unpleasant sight. This paper presents and discusses the results of microstructural study on the effectiveness of commercial polymer emulsion as cement additives to mitigate efflorescence on cement-based products that are dry-cured in the concrete laboratory at daily room temperature (T) and relative humidity in the range of 18°C–28°C and 65%–90%, respectively. Polymers used as cement additives were styrene acrylic ester (SAE) and styrene butadiene rubber (SBR) emulsion. Due to their pore-blocking characteristics and interaction with cement to improve mortar quality, they are added into cement to form mortar used for repair purposes. In order to investigate on how they can microstructurally influence efflorescence formation, efflorescence intensities (EI) in terms of percentages of CaCO3 resulting from the combination of puddle test and standard chemical method were compared systematically between all samples on 28, 60 and 90 days and the findings were discussed and corroborated physicochemically using initial surface absorption test, X-ray diffraction (XRD), thermogravimetric analysis (TGA) and morphology using scanning electron microscopy (SEM). Results indicated that 10% and 5% SAE addition significantly reduced primary efflorescence and secondary efflorescence, respectively, in comparison to SBR and Control. The influence were on chemical reactivity, interaction between polymer and cement and on the movement of the polymer particles within the hydrating mortar as hydration progressed to form pore-blocking effects in the microstructures of cement-based materials and were reflected in the XRD patterns, TGA/DTG analysis, SEM images and the decreased initial surface water absorption.
efflorescence, polymer, XRD, TGA/DTG, SEM, ISAT
 Crouchore, P.N., Color: a force in construction. Concrete International, 7(11), pp. 43–45, 1985.
 Nasvik, J., Diagnosing problems with decorative concrete. Concrete Construction, 2003.
 Higgins, D.D., Effl orescence on concrete. Appearance Matters, No.4. Cement and Concrete Association: UK, 8 pp, 1982.
 Neville, A., Effl orescence-surface blemish of internal problem? Part 2: Situation in practice. Concrete International, 24(9), pp. 85–88, 2002.
 Neville, A., Effl orescence-surface blemish of internal problem? Part 1: The knowledge. Concrete International, 24(8), pp. 86–90, 2002.
 Bensted, J., Effl orescence-prevention is better than cure. Concrete, 34, pp. 40–41, 2000.
 Kresse, P., Coloured concrete and its enemy: effl orescence. Chemistry and Industry, pp. 93–95, 1989.
 Horgnies, M., Willieme, P. & Gabet, O., Infl uence of the surface properties of concrete on the adhesion of coating: characterization of the interface by peel test and FT-IR spectroscopy. Progress in Organic Coatings, 72(3), pp. 360–379, 2011. doi: http://dx.doi.org/10.1016/j.porgcoat.2011.05.009
 Deichnel, T., Effl orescence-origins, causes, counter-measures. Betonwerk+Fertigteil-Technik, 48, pp. 590–597, 1982.
 Kresse, P., Effl orescence-mechanism of occurrence and possibilities of prevention. Betonwerk+Fertigteil-Technik, 53, pp. 160–168, 1987.
 Kresse, P., Effl orescence and its prevention. Betonwerk+Fertigteil-Technik, 57, pp. 84–88, 1991.
 Kresse, P., Studies of the phenomenon of effl orescence on concrete and asbestos cement. Betonwerk+Fertigteil-Technik, 49, pp. 560–568, 1983.
 Bensted, J., Effl orescence-a visual problem on buildings. Construction Repair, 8, pp. 47–49, 1994.
 Dhir, R.K., McCarthy, M.J. & Newlands, M.D., Challenges in designing concrete durability: a sustainable approach. University of Dundee, UK: Concrete Technology Unit, 2009.
 Older, I., Hydration, setting and hardening of Portland cement. Lea’s Chemistry of Cement and Concrete, 4th edn., Arnold: London, 1998.
 Taylor, H.F.W., Cement Chemistry, 2nd edn., Thomas Telford: London, 1997. doi: http://dx.doi.org/10.1680/cc.25929
 Dow, C. & Glassier F.P., Calcium carbonate effl orescence on Portland cement and building materials. Cement and Concrete Research, 33, pp. 147–154, 2003. doi: http://dx.doi.org/10.1016/S0008-8846(02)00937-7
 Mohamed, S.N., Hamdan, S. & Yakub, I., Calcium carbonate effl orescence on pozzolanic modifi ed mortar. International Journal of Advancements Civil Structural and Environmental Engineering-IJACE, 1(1), pp. 56–59, 2013.
 Lanzon, M., Garrido, A. & Garcia-Ruiz, P.A., Stabilization of sodium oleate as calcium oleate in cement-based mortars made with limestone fi llers. Construction and Building Materials, 25(2), pp. 1001–1008, 2011. doi: http://dx.doi.org/10.1016/j.conbuildmat.2010.06.079
 Izaguirre, A., Lanas, J. & Alvarez, J.I., Effect of water-repellent admixtures on the behaviour of aerial lime-based mortars. Cement and Concrete Research, 39(11), pp. 1095–1104, 2009. doi: http://dx.doi.org/10.1016/j.cemconres.2009.07.026
 Ohama, Y., Recent progress in concrete-polymer composites. Advance Cement Based Materials, 5(2), pp. 31–40, 1997. doi: http://dx.doi.org/10.1016/S1065-7355(96)00005-3
 Ohama, Y., Polymer-based admixtures. Cement and Concrete Composites, 20(2–3), pp.189–212, 1998. doi: http://dx.doi.org/10.1016/S0958-9465(97)00065-6
 Ohama, Y. & Chandra, S., Polymers in Concrete, CRC Press: Florida, 1994.
 Aziz, M.A., Engineering Materials. Kazi Mahfuzur Rahman: Dhaka, 1995.
 Gomes, C.E.M. & Ferreira, O.P., Analysis of microstructural properties of VA/VEAVA coplymer modifi ed cement pastes. Polimeros: Ciencia e Tecnologia, 15(3), pp. 193–198, 2005. doi: http://dx.doi.org/10.1590/S0104-14282005000300009