Styrene Acrylic Ester Research Articles

Synthesis of silane-modified styrene-acrylic ester emulsion and its inhibition mechanism on whitening of calcium aluminate cement mortar

A new polymer, triethoxyvinylsilane-modified styrene-acrylic ester emulsion (TMSA), was synthesized through emulsion polymerization. The effect of TMSA on the whitening of calcium aluminate cement (CAC) mortar was investigated. The results showed that TMSA had an excellent inhibition effect on the whitening of the CAC mortar with only 0.8 % - 1.6 % addition. Analysis of the micro-morphology and Raman spectra revealed that the white deposits on the surface of the mortar were C4AC(_)H11 and CaCO3, whereas TMSA addition effectively inhibited the formation of C4AC(_)H11 and reduced the occurrence of CaCO3. Through investigating the hydration, Ca2+ concentration, capillary water absorption and pore structure, it was found that the effect of the CAC hydration on the whitening of the mortars was inessential, whereas there was a strong link among whitening, capillary water absorption and macro-capillary pores. The addition of TMSA not only reduced the concentration of Ca2+ which was the source of the whitening, but also reduced the formation of macro-capillary pores in the CAC mortar that led to a significant reduction in the capillary water absorption, thus weakening the mobility of pore solution in the mortar and hindering the migration of Ca2+ to the mortar surface. Based on these two aspects, TMSA effectively inhibited the whitening of the CAC mortar.

Effect of cyclic curing conditions on the tensile bond strength between the polymer modified mortar and the tile

Cementitious tile adhesive is a typical polymer-modified mortar, whose tensile bond strength is strongly affected by its curing conditions. Tile-back glue, a composite based on polymer emulsion, is a key role that used to improve the bond strength between the mortar and the tile. In this work, 4 artificial cyclic curing regimes with designed conditions were used to simulate the natural curing, and a constant curing was set as reference. Taking tiles coated with back glue as substrates, the tensile bond strengths of the VAE (vinyl acetate-ethylene) or SAE (styrene-acrylic ester) modified mortar with VAE or SAE content of 0 %, 3 %, 6 %, 9 % and 12 % were investigated. The results show that higher content of polymers, higher strength would be obtained under low RH cyclic curing, but it is different under high RH cyclic curing. Low RH cyclic curing improves the strength, while high RH cyclic curing generally inhibits the strength development of the polymer modified mortars. The results from SEM show that the added polymer forms a continuous film network structure at the mortar-tile interface region, thus significantly increases the strength with content increase under low RH cyclic curing. Furthermore, it was found that the morphology and distribution of the generated film network are seriously influenced by the experienced cyclic curing conditions, which have significant impact on the tensile bond strength of the cured mortar, especially in cases of the VAE modified mortars. Additionally, the given cyclic curing reduces the contents of AFt in the hydration products, while in the most cases, the contents of CH increase.

Evaluation of Latex Polymeric mortar properties for laying bricks in non-structural masonry

Polymeric mortars (PM) or Latex Polymeric mortars are a class of building material that can replace Portland cement mortar. PM are produced with polymer resin, which acts as a binder that allows excellent bonding between brick layers. The goal of this study was to evaluate polymeric mortars based on poly (styrene-acrylic ester) latex, water based, cementless and ready to use in laying bricks in non-structural masonry. The polymeric mortars were obtained with different polymer contents, starting with a minimum value of content. The properties were evaluated using different techniques aiming to find the most suitable techniques to analyze these new materials. The mortars were characterized by the consistency in the fresh state, mechanical properties (tensile and compressive strength), thermal properties, thermal resistance and the swelling degree. SEM and optical microscopy showed that surface morphology and porosity distribution varied with change in resin content. Thus, most of the analyzed properties are sensitive to variations of the polymeric latex content. Small increments in the formulation increased mechanical properties, making the material obtained more compatible and suitable for commercial application. In general, the mortars showed different porosity for high and low polymeric latex content. The methodologies used to characterize the mortars showed to be adequate for the new material, except for the shear strength in ceramic blocks, which showed the rupture of the blocks instead of the mortar.

Effect of Polymer Additives on the Microstructure and Mechanical Properties of Self-Leveling Rubberised Concrete.

The materials based on concrete with an addition of rubber are well-known. The interaction between concrete components and rubber particles is in the majority cases insufficient. For this reason, different substances are introduced into concrete-rubber systems. The aim of this paper is to establish the influence of five different polymer additives, i.e., 1. an aqueous dispersion of a styrene-acrylic ester copolymer (silanised) (ASS), 2. water dispersion of styrene-acrylic copolymer (AS), 3. anionic copolymer of acrylic acid ester and styrene in the form of powder (AS.RDP), 4. water polymer dispersion produced from the vinyl acetate and ethylene monomers (EVA), 5. copolymer powder of vinyl acetate and ethylene (EVA.RDP)) on the properties of the self-leveling rubberised concrete. Scanning electron microscopy has allowed to establish the interaction between the cement paste and rubber aggregates. Moreover, the compressive strength and flexural strength of the studied materials were evaluated. The results indicate that the mechanical properties depend extensively on the type as well as the amount of the polymer additive introduced into the system.

Polymer and non-polymer admixtures for concrete roofs: Thermal and mechanical properties, energy saving and carbon emission mitigation prospective

Buildings are accountable for the enormous energy consumption in the world. Therefore, energy-efficient building materials are inevitable in modern construction practices to diminish global energy consumption. In this paper, three industrial wastes (fly ash, ground granulated blast-furnace slag, and silica fume), four other admixtures (bentonite, metakaolin, oyster shell, and zeolite), and two polymer admixtures (Styrene-butadiene rubber, styrene-acrylic ester) are considered for the concrete to explore their potential for air conditioning cost-savings, carbon mitigations, and payback periods in buildings of hot-dry (Jodhpur, India) and cold climates (Thessaloniki, Greece). The mechanical and thermophysical properties were measured for admixture-based concretes. The results revealed that among all admixtures studied, styrene-acrylic ester concrete roof exhibited better thermal performance with adequate compressive strength (34 MPa). The best economic benefit of styrene acrylic ester concrete roof in hot-dry/cold climatic conditions leading to the highest total air conditioning cost-savings (1.01 $/m2/1.53 $/m2), highest life cycle saving costs (48.9/31.2 $/m2), highest carbon mitigation (19.26/7.53 kg of CO2/year), and acceptable payback periods (11.6/8.4 years). The results of this research help engineers and architects to select the best admixtures for the concrete in terms of mechanical strength, energy efficiency, and carbon emission mitigation potential.

Equilibrium, kinetics and thermodynamics studies of Cd sorption onto a dithizone-impregnated Amberchrom CG-300m polymer resin

Amberchrom CG-300m, a styrene acrylic ester polymer resin, was studied for the first time as sorbent for metal ion sorption in a solid-phase extraction system. The polymer sorbent was modified via impregnation with dithizone to improve its efficiency. Efficiency of the modified sorbent improved by more than 47%. The loading capacity of the resin is 3.2 mg dithizone per gram of sorbent. The mechanisms of Cd(II) sorption from aqueous solutions are presented. Capacity of the modified resin for Cd(II) was investigated in batch experiments as a function of pH, initial metal ion concentration, temperature and time. Maximum capacity of 0.551 mg Cd(II) per gram of sorbent was achieved. The dimensionless separation factor, 0 < RL < 1, associated with the Langmuir isotherm (at T = 294 K) signifies sorption of Cd(II) was favorable, as do negative values of free energy of sorption (ΔG) at temperatures exceeding 293 K. Sorption was endothermic (ΔH > 0) while ΔS > 0 reflects the affinity of the sorbent towards Cd(II). The pseudo-second order model proved to be the best fit model for Cd(II) sorption kinetics data. Particle-diffusion models suggest sorption follows film as well as pore diffusion mechanisms.

The effect of polymer dispersions on the early hydration of calcium sulfoaluminate cement

The influence of three polymer dispersions [styrene–butadiene copolymer (SB), styrene–acrylic ester copolymer (SA) and polyacrylic ester (PA)] on the hydration of calcium sulfoaluminate (CSA) cement within 72 h was investigated by using isothermal conduction calorimetry, X-ray diffraction analysis and thermal gravimetric analysis. The results indicate that these three polymer dispersions perform different influences on the hydration heat flow of CSA cement during different periods, they all postpone the occurrence time of the maxima peaks, and its extent is mainly dependent on the addition amount. Polymer dispersions manifest great retardation on the initial hydration of CSA cement, and the effect is much more significant within 1 h. In this stage, the generation of ettringite is strongly delayed; however, the formation of ettringite is accelerated by these polymer dispersions at and after 2 h. Among these three polymer dispersions, PA demonstrates the highest acceleration effect on the hydration degree.

Influence of polymer latex on the setting time, mechanical properties and durability of calcium sulfoaluminate cement mortar

In this study, three different types of polymer latexes (styrene butadiene rubber (SBR), styrene acrylic ester (SAE) and polyacrylic ester (PAE)) with three different dosages (0%, 10% and 20%) were employed to prepare polymer latex modified calcium sulfoaluminate (CSA) cement mortar based on the same workability. The setting time, mechanical properties including strength, shrinkage, weight loss, water capillary adsorption, anti-penetration property and durability properties such as resistance to freeze-thaw cycle, carbonization and sulfate attack were measured. The experimental results show that polymer latexes perform good water-reduction effect and delayed setting behavior on CSA cement mortar. Meanwhile, polymer latexes are helpful to enhance the mechanical properties of CSA cement mortar. Generally, SBR latex modified mortar performs the best properties in terms of strength, weight loss, water capillary adsorption and anti-penetration property. Addition of polymer latex decreases strength when subjected to extreme conditions, however, polymer latex modified mortars perform good resistance to carbonization and sulfate attack, although only SBR latex improves the freeze-thaw cycle resistance.

Effect of waste glass content on the physico‐chemical and mechanical properties of styrene acrylic ester blended cement mortar composites

This study focuses on the partial substitution effect of ordinary Portland cement (OPC) by different ratios of waste glass powder (5%, 10%, and 20% by weight of cement) on the performance of blended cement mortars. The hardened blended cement mortars were first cured under tap water for different time intervals 3, 7, 28, and 90 days. However, the effect of addition of 10% styrene‐acrylic ester as well as the influence of different doses of gamma rays on the physico‐chemical and mechanical properties of polymer modified blended cement mortar specimens were discussed. Compressive strength, total porosity, and water absorption percentages were measured. The experimental results showed that the physico‐chemical and mechanical properties of blended cement mortars specimens improved as the waste glass content increases up to 20%. In addition, irradiated SAE blended cement mortar composites containing 20% waste glass showed an enhancement in its properties as compared to neat cement (0%WG content) composites. The results were confirmed by X‐ray diffraction, thermogravimetric analysis, and scanning electron microscopy. POLYM. COMPOS., 39:985–996, 2018. © 2016 Society of Plastics Engineers

Efecto de la sulfonación del estireno-éster acrílico sobre las propiedades de las membranas de intercambio protónico

In this work was studied the effect of sulfonation of styrene-acrylic ester and of titanium dioxide nanoparticles on the proton exchange membranes. It was evaluated the physicochemical characterization of membranes, such as, the water uptake capacity, ion exchange capacity, the mechanic properties of stress/strain, and the chemical functional groups present in the membrane structure by FTIR analysis. Water uptake increases with increasing the time of sulfonation reaction, reaching 60.9% after 8hours of sulfonation; while, ion exchange capacity of loaded-sulfonated membrane increases with increasing the time of sulfonation reaction and with increasing the TiO2 load, reaching 0.39 meq/g for 8hours and 4% TiO2. It was observed that the elasticity of the synthesized membranes increases with increasing the time of sulfonation reaction, and it decreases with the addition of the TiO2 load. This physicochemical property set allows to consider the membrane with high potential of application in the fuel cells area.

Microstructural study on the effectiveness of commercial polymer emulsion as cement additives to mitigate efflorescence

The occurrence of calcium carbonate (CaCO 3 ) effl orescence 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 effl orescence 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 infl uence effl orescence formation, effl orescence intensities (EI) in terms of percentages of CaCO 3 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 fi ndings 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 signifi cantly reduced primary effl orescence and secondary effl orescence, respectively, in comparison to SBR and Control. The infl uence 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 refl ected in the XRD patterns, TGA/DTG analysis, SEM images and the decreased initial surface water absorption.

Thermal, mineralogical, and microstructural characterizations of irradiated polymer blended cement mortar composites

In this study, the effects of styrene–acrylic ester (SAE), nanocalcined clay (NCC), and irradiation dose on the thermal, mineralogical, and microstructural characterizations of irradiated polymer‐blended cement mortar composites have been investigated. The composites were prepared by partial replacement of cement with 5 and 10% NCC and mixed with sand, SAE latex was added with different ratios (2, 4, 6, 8, 10, and 15%); the composites were subjected to various doses of γ‐irradiation ranged from 10 to 50 kGy. Physicomechanical properties, thermogravimetric analysis, X‐ray diffractometry, and scanning electron microscopy techniques were carried out. Mechanical investigation manifested that composites loaded with SAE up to 8% showed the best mechanical performance as compared with composites contains 10 and 15% SAE. POLYM. COMPOS., 36:1849–1858, 2015. © 2014 Society of Plastics Engineers

Influence of Styrene-Acrylic Ester Dispersion on the Early Hydration of Cement

Early hydration of cement in the presence of styrene-acrylic ester (SAE) dispersion was investigated, and the hydration heat, hydration degree, and hydrates were analyzed using isothermal calorimeter, XRD, and ESEM. The results show that SAE dispersion prolongs the induction period, postpones and shortens the accelerating period, and inhibits the decelerating and stable periods of cement hydration. The hydration heat and hydration degree of cement in the presence of SAE dispersion are less than those of the control. SAE dispersion inhibits the formation of C4AH13and thus AFt, and more SAE dispersion brings stronger influence, but it enhances the stability of AFt. AFt generation during the early hydration period is controlled gradually by the reaction of C4AH13generation with increasing SAE dispersion, but this is controlled by the reaction of C4AH13consumption for the control paste. Besides, SAE dispersion retards and inhibits the formation of CH and C-S-H and also changes their morphology.

Experimental and numerical analysis of new bricks made up of polymer modified-cement using expanded vermiculite

In this paper, the properties of the cement mortar modified with styrene acrylic ester copolymer were investigated. Expanded vermiculite as lightweight aggregate was used for making the polymer modified mortar test specimens. To study the effect of polymer-cement ratio and vermiculite-cement ratio on various properties, specimens were prepared by varying the polymer-cement and vermiculite-cement ratios. Tests of physical properties such as density, water absorption, thermal conductivity, three-point flexure and compressive tests were made on the specimens. Furthermore, a coupled thermal-structural finite element model of an entire corner wall was modelled in order to study the best material configuration. The wall is composed by a total of 132 bricks of <TEX>$120{\times}242{\times}54$</TEX> size, joined by means of a contact-bonded model. The use of advanced numerical methods allows us to obtain the optimum material properties. Finally, comparisons of polymer-cement and vermiculite-cement ratios on physical properties are given and the most important conclusions are exposed.

Innovations Based on PCC

Abstract. In this paper, three examples for the application of PCC are presented, which exceed the well established use as restoration material and show the great innovation potential of these materials. The first example shows an innovative development of a polymer-modified self-compacting concrete (SPCC) for the restoration of vertical facing concrete surfaces. In the second example PCC was for the first time applied as construction concrete to a bridge building. The last instance describes the potential of the SPCC for special applications in mechanical engineering. A styrene acrylic ester dispersion and different sorts of cement were used. The polymer/cement-ratio varied from 0.05 to 0.10. The water/cement-ratio depended on the requirements of the different PCC. The essential laboratory and field tests as well as the results are described.

Influences of HPMC on adsorption of styrene-acrylic ester latex particles on cement grains

In order to understand why polymer-modified mortars (PMMs) with hydroxypropylmethyl cellulose (HPMC) often show better properties than that without HPMC, the influence of HPMC on the adsorption of styrene-acrylic ester (SAE) latex particles on cement grains was studied through the particle size distribution and the zeta potential of latex modified cement paste (LMCP) with and without HPMC keep the latex/cement ratio (L/C) to 10%. The differences between the calculated and measured particle size distribution curves of LMCP indicate strong interactions between latex particles and cement grains in fresh cement pastes. The particle size distribution results show that the adsorbed rate of SAE on cement is 75.24% in LMCP, while the adsorbed rate of SAE latex particles in LMCP with HPMC is 4% lower than that in LMCP without HPMC. The zeta potential results show that the zeta potential of LMCP is negative, the equilibrium zeta potential of LMCP with HPMC is more negative than that of LMCP without HPMC and decreases with the increase of the HPMC to cement ratio (HPMC/C). The microstructures of hardened LMCP with and without HPMC were observed using scanning electronic microscopy (SEM). Without etching of LMCP with or without HPMC, the polymer films are more easily seen in pores while hard to found at the cement matrix. After etching the specimen in diluted hydrochloric acid (HCl), coherent polymer films were observed. The differences of the polymer films in samples prepared with different procedures, that is the specimens stored in absolute alcohol or not, show that they are composite films of SAE latex and HPMC in LMCP with HPMC. Higher the HPMC/C is, bigger the covered area of the polymer films is on the surface of pores, and more rigid the polymer films are, what can be confirmed from the tensile test results of films made from the HPMC and SAE latex mixture that show decreased elongation at break and increased tensile strength with the increase of HPMC to latex ratio (HPMC/L).

Influence of superplasticiser and mixing procedure on properties of styrene–acrylic ester latex modified mortars

The influence of different superplasticisers and mixing procedures of latex on the properties of styrene–acrylic ester latex-modified mortars (LMM) was studied. The results indicate that the water-reducing effect of latex in LMM with naphthalene formaldehyde condensate superplasticiser (NF) is 27% higher than that in LMM with polycarboxylic superplasticiser, which demonstrates that more polymer particles are free in pores (not adsorbed by cement grains) and act as ball bearing in LMM with NF. The mixing procedure of latex influences the microstructure and mechanical properties of LMM. LMM added latex and water simultaneously (LMM-S) show higher compressive, flexural and adhesive strength at later stage than LMM added latex later than water (LMM-L). The scanning electronic microscopy observation results also illustrate that more polymer particles are adsorbed by cement grains in LMM-S than in LMM-L.

Relationship between Mechanical Properties of Modified Cementitious Composites and Properties of Polymer Films

Keep the mixing amount of styrene-acrylic ester (SAE) constant, the mixtures of SAE and cellulose ethers (CE) were confected with tap water and filtered cement water respectively. The relationship between the mechanical properties of polymer modified cementitious composites (PMCCs) and the properties of polymer films was studied. It is discovered that when the cellulose ether-latex ratio (CE/L) increases, the polymer films become fragile. The properties of polymer films mutate when CE/L increases from 0.5‰ to 1.0‰. The tensile strength of the polymer films with filtered cement water is higher than that with tap water. However, the elongation at break is lower than that with tap water. The compressive strength of PMCCs decreases with the increase of the tensile strength of polymer films. Yet, the flexural strength of PMCCs does not relate to the properties of polymer films. The adhesive strength increases when CE/L increases from 0 to 1.0‰, but no longer after that.

Function of styrene-acrylic ester copolymer latex in cement mortar

This paper focuses on the effect of the styrene-acrylic ester copolymer (SAE) latex on the performance of cement mortar, through studying on the water-reduction and water-retention effects of the SAE latex in the mortar, and the influence of the SAE latex on the air-content and the bulk density of the fresh mortar and the bulk density, compressive and flexural strengths, shrinkage rate, water capillary adsorption and anti-penetration capacity of the hardened mortar. The experimental results show that the SAE latex has good water-reduction and water-retention effects in mortar. The SAE latex has also air entrainment effect, increasing the air content and reducing the bulk density of the fresh mortar. The apparent bulk density and dry bulk density of the hardened mortars decrease with the increase of the SAE latex/cement-ratio (mp/mc) and the change is in accordance with that for the bulk density of the fresh mortar. The SAE latex influences the development of the compressive strength but slightly on the flexural strength, and improves the toughness, shrinkage property, waterproofing quality and anti-penetration capacity of the mortar significantly.

Effect of Styrene Acrylic Ester Polymer on Mortar Render Properties

This paper summarizes some the important findings from a research project designed to study the effect of inclusion of styrene acrylic ester (SAE) polymer as an additive, on the properties of mortar render. Properties studied included shrinkage, compressive, tensile and adhesive strengths, water absorption, workability and durability. From test specimens cast using polymer/cement content (PCC) from 0 to 0.44 under laboratory conditions, an increase in adhesive strength from 0.3 to 2.6MPa, a decrease in shrinkage from 0.09% to 0.05% and a decrease in water absorption from 15% to 7% were observed. Among the six PCC tested in this study, it was found that mortar specimens prepared with 0.06 PCC obtained using 8% of SAE latex concentration has the most consistent performance and durability for rendering purposes. The results reflect the importance of having a proper mix design especially when mortar render is exposed to direct harsh weathering. This report resulted with recommendations for mix design of mortar render in the achievement of good physical performance when using mortar render.