International Journal of Technology 11(2) 259-268 (2020) Received February 2020 / Revised March 2020 / Accepted March 2020 International Journal of Technology http://ijtech.eng.ui.ac.id Utilization of Poly(Polyvinyl Alcohol-g-2-Ethylhexyl Acrylate) as Admixture for Mortar Lyazzat Bekbayeva 1* , El-Sayed Negim 2 , Yeligbayeva Gulzhakhan 1 , Eshmaiel Ganjian 3 1 School of Chemical and Biological Technologies, Satbayev University, 22 Satpayev Street, 050013 Almaty, Kazakhstan 2 School of Chemical Engineering, Kazakh-British Technical University, 106 Walikhanov Street, Almaty, 050010, Kazakhstan 3 School of Energy, Construction and Environment, Faculty of Engineering, Environment & Computing, Sir John Laing Building, JL138, Coventry University, Coventry, CV1 2HF Abstract. We investigated the physico-mechanical properties of mortar mixed with copolymers based on polyvinyl alcohol (PVA) and 2-ethylhexyl acrylate (2-EHA) and synthesized by grafting using ammonium persulfate (APS) as an initiator. Increasing the amount of 2-EHA in the copolymer from 4% to 8% reduced the water/cement (W/C) ratio, the initial and final setting times, and the water absorption of mortar, while it increased its compressive strength. Keywords: Admixture; Cement; Copolymer; Mortar; PVA; Workability 1. Introduction A number of researchers have investigated concrete admixtures based on polymers to improve different properties of concrete, such as workability, setting time, and compressive strength (Akers, 2001; Duggal, 2008; Plank and Sachsenhauser, 2009). These admixtures are used in various latexes, powders, and water-based and epoxy resins (Liao et al., 2006; Zingg et al., 2009) to enhance the physical and mechanical characteristics of cement, mortar, and concrete (Ashadi et al., 2015). The main mechanism of polymer addition to concrete is the formation of a thin film on the surface of the cement aggregate, as well as pores, which exhibit good adhesion and promote compressive strength and an increase in bending (Sakai and Sugita, 1995; Allahverdi et al., 2010). PVA is a hydrophile polymer often used in industrial applications as a binding agent, modifier, and aggregate surface pretreatment and fiber reinforcement agent in cement-based composite substances (Kim and Robertson, 1998; Kim et al., 1999; Niken et al., 2017). Generally, adding PVA to cement and cement-based materials, such as mortar and concrete, in small amounts improves their properties (Kim et al., 1999; Singh and Rai, 2001). Singh and Rai (2001) found that the incorporation of 3.0-wt.% PVA to cement pastes increased their strength and decreased their porosity. Furthermore, adding 1.0-wt.% PVA increased the flexural strength of cement pastes, as observed by Knapen and Van Gemert (2015). On the other hand, Sathidevi and Pushpendra (2017) demonstrated that the compressive strength of cement pastes as observed by Knapen and Van Gemert (2015). On the other hand, Sathidevi and Pushpendra * Corresponding author’s email: lyazzat_bk2019@mail.ru, Tel.: +77086277233 doi: 10.14716/ijtech.v11i2.3927