Polymer-cement Composites Research Articles

The Influence of Post-Curing Periods On Polymer-Mortar Composites In Corrosive Media

Petroleum tanks and pipes made of steel or concrete suffer from the interaction between the petroleum products and the materials of the tank or pipe. This work aims to overcome this problem by adding polymer to the cement mortar and post cure it at the proper period to modify its behavior when encountering petroleum products. Unsaturated polyester was selected to prepare polymer cement composites. Four sets of polymer cement composites were prepared. Two sets were cured at room temperature, but one was kept without immersing in any solution. The other sets were post-cured at 50ºC for two and four hours. Six groups of polymer cement composite specimens were immersed in a solution. The solutions were water, 1N and 2N NaCl, kerosene, benzene, and oil engine. The hardness and compressive strength were evaluated after 30 days. The hardness of the specimens was altered according to the solution immersed. The best water absorption and compressive strength results were obtained two hours post-curing specimens, whatever the solution was immersed in. The corrosion rate for all specimens in every solution was low. Again, the lowest corrosion rate was obtained after two hours of post-curing specimens, which indicates that the addition of polymer an

Immobilization of radioactive sulphate waste simulate in polymer–cement composite based on recycled expanded polystyrene foam: evaluation of the final waste form resistance for Cs-134 and Co-60 leachability

The present study investigates to incorporate spiked sulfate solution simulate into polymer–cement composite (PCC) based on recycled expanded polystyrene foam. The main aim is to convert the waste stream into leach resistance solid forms able to slow down or even to retard the back release of hazardous radionuclides to the surrounding. Effective parameters e.g. leachant medium, temperature, radioactivity contents, leachant volumes and radionuclides speciation versus the leaching time were studied. The incremental leach rate (Rn, cm/day) and the leach index (Lx) were evaluated for the final waste form after 145 days. The experimental results revealed that the Lx for the all variances can fulfil the waste acceptance criteria for the disposal facility and are above the threshold value of 6. Moreover, leach rate percentages for Cs-134 and Co-60 were not exceeding 2%. The acquired data, based on lab leaching experiments, can recommend the developed PCC under consideration for solidification of radioactive sulphate waste stream safely.

Recent Advances in Polymer Nanocomposites: Unveiling the Frontier of Shape Memory and Self-Healing Properties-A Comprehensive Review.

Shape memory and self-healing polymer nanocomposites have attracted considerable attention due to their modifiable properties and promising applications. The incorporation of nanomaterials (polypyrrole, carboxyl methyl cellulose, carbon nanotubes, titania nanotubes, graphene, graphene oxide, mesoporous silica) into these polymers has significantly enhanced their performance, opening up new avenues for diverse applications. The self-healing capability in polymer nanocomposites depends on several factors, including heat, quadruple hydrogen bonding, π-π stacking, Diels-Alder reactions, and metal-ligand coordination, which collectively govern the interactions within the composite materials. Among possible interactions, only quadruple hydrogen bonding between composite constituents has been shown to be effective in facilitating self-healing at approximately room temperature. Conversely, thermo-responsive self-healing and shape memory polymer nanocomposites require elevated temperatures to initiate the healing and recovery processes. Thermo-responsive (TRSMPs), light-actuated, magnetically actuated, and Electrically actuated Shape Memory Polymer Nanocomposite are discussed. This paper provides a comprehensive overview of the different types of interactions involved in SMP and SHP nanocomposites and examines their behavior at both room temperature and elevated temperature conditions, along with their biomedical applications. Among many applications of SMPs, special attention has been given to biomedical (drug delivery, orthodontics, tissue engineering, orthopedics, endovascular surgery), aerospace (hinges, space deployable structures, morphing aircrafts), textile (breathable fabrics, reinforced fabrics, self-healing electromagnetic interference shielding fabrics), sensor, electrical (triboelectric nanogenerators, information energy storage devices), electronic, paint and self-healing coating, and construction material (polymer cement composites) applications.

The Influence of Waste Perlite Powder on Selected Mechanical Properties of Polymer–Cement Composites

The subject of this paper is the influence of the partial substitution of cement with mineral additive on the properties of polymer–cement composites (PCCs). Although there is considerable research on the use of perlite in cement concrete, most of the previous studies were conducted with expanded perlite or ground waste perlite, and there is a lack of results evaluating its suitability with polymer–cement composites. To fill this gap, this paper presents the mechanical characteristic of PCC mortars containing waste perlite powder. The modification consisted of replacing part of the cement with waste perlite powder, a byproduct formed during the expansion and fractionation of perlite. The granulometric characteristics of the powder were compiled, and its specific surface area and density were determined. A chemical composition analysis was also carried out. An aqueous dispersion of styrene–acrylic copolymer was used as a polymer modifier. The proportions (by mass) between the contents of the PCC composite components, i.e., cement/polymer (0 to 20%) and cement/mineral powder (0 to 15%), were used as material variables. The technical characteristics tested included the compressive, flexural, and tensile strengths at 28 and 90 days of curing. The compositions of the tested composites were determined using the statistical planning of the experiment. At a low polymer-modifier content in PCC mortars (2.93%), the tested mechanical strengths decreased by five times, with a 6-fold increase in waste content. For mortars containing more than 10% of the polymer modifier, no effect of waste material powder on the flexural strength was observed, while with relatively minor reductions in compressive strength of 2% and 5% and tensile strength of 4% and 2% were observed after 28 and 90 days of curing, respectively. It was shown that it is possible to use waste perlite powder as an ingredient in construction polymer–cement composites, while there is a limiting waste content, above which there is a deterioration in mechanical properties.

EVALUATION OF CEMENT POLYMER COMPOSITES USING SPSS ANALYSIS

Cement Polymer Mixtures are made of Cement, sand, or bulk polymers are made using polymers added to improve their compressive strength, fatigue resistance, impact, and durability. Hydraulic cement polymer composites, created with modern polymer technology, are well-known for enhancing the development of composite materials and new products. This technology aims to improve both polymer cement for new construction and its use in repairing old cement. The adhesive properties of polymer cement allow for correction and bonding of both polymer-based and conventional cement. Cement-based composite materials, such as hardened cement paste, are formed by the combination of cement, water hydration, various minerals, metals, and polymeric materials. Different combinations of these materials can result in cement binders that are used for construction. Cement, a chemical substance used as a binder, sets and hardens to bind things together. It is rarely used alone and is typically combined with sand and gravel. Polymer cement is a type of cement-polymer composite where conventional cement hydrates are replaced by polymer binders or liquid resins. It is prepared by completely replacing the hydrate binders of cement with the polymer binders or liquid resins. This mixture forms a cement-polymer composite. Cement-polymer composites are durable materials that exhibit long service life and can withstand harsh environmental conditions. They are not affected by extreme temperatures, whether hot or cold, as dry concrete has a low coefficient of expansion and can accommodate moderate movements in the design. Evaluation parameters for cement include calcium oxide, magnesium oxide, silicon dioxide, aluminum oxide, sodium oxide, potassium oxide, and sulfur trioxide.

Experimental Study and Finite Element Analysis on the Modification of Fast-Hardening Polymer Cement Composite Material Applied to the Anchorage Zone of Expansion Joint

Bridges’ expansion joints are prone to damage during operation, and repairing them often requires interruption of traffic, the impact of which can be minimized by using fast-hardening and early-strength expansion joint materials. In this study, a fast-hardening polymer cement composite (PCC) was developed using sulfate aluminate cement and ordinary silicate cement as binding agents and polymer powder as admixture. To improve the crack resistance of the material, several types of fibers were added and the effects of different fiber types and admixtures on the crack resistance of the material were compared using SCB tests. The results showed that the best effect of improving the crack resistance of concrete was achieved with a volume fraction of 0.5% of basalt fibers. Then, a test method for the interfacial shear properties of PCC materials and ordinary concrete was established, and the cohesive force model was selected as the interface simulation parameter for finite element analysis and compared with experimental data to verify its feasibility. Finally, based on the previously obtained PCC material parameters, a solid model of the expansion joint anchorage zone was established to study the mechanical properties of the expansion joint anchorage zone with the application of fast-hardening PCC material. This research provides a new way to develop fast-hardening and early-strength expansion joint materials with high crack resistance.

Distribution and curing kinetics of waterborne epoxy resin in repair system: Characterization and quantification by 1H low-field NMR

Cement-based mortars are commonly modified with Waterborne Epoxy Resin (WER). However, the curing kinetics of WER in mortars has never been quantified up to now. This study proposed using 1H low-field nuclear magnetic resonance (1H LF-NMR) to quantitatively determine the curing kinetics of WER in polymer-cement composite. The distribution and curing of WER in repair systems was also explored using 1H LF-NMR. To avoid the interference of the NMR water signal, heavy water was used to prepare repair mortar. It was found that the curing reaction of WER in a mortar was significantly influenced by the cement hydration. It starts to accelerate when the cement hydration stepped into an acceleration period. Moreover, the 1D spatial NMR signal distribution showed that WER in the repair materials permeated into the substrate with water, which is affected by both the W/C of the repair and the RH of the substrate. The WER was enriched at the interface between the substrate and the repair mortar and exhibited a gradient in the distribution both upwards into the repair mortar and downwards into the substrate.

Toward Self-Healing Concrete Infrastructure: Review of Experiments and Simulations across Scales.

Cement and concrete are vital materials used to construct durable habitats and infrastructure that withstand natural and human-caused disasters. Still, concrete cracking imposes enormous repair costs on societies, and excessive cement consumption for repairs contributes to climate change. Therefore, the need for more durable cementitious materials, such as those with self-healing capabilities, has become more urgent. In this review, we present the functioning mechanisms of five different strategies for implementing self-healing capability into cement based materials: (1) autogenous self-healing from ordinary portland cement and supplementary cementitious materials and geopolymers in which defects and cracks are repaired through intrinsic carbonation and crystallization; (2) autonomous self-healing by (a) biomineralization wherein bacteria within the cement produce carbonates, silicates, or phosphates to heal damage, (b) polymer-cement composites in which autonomous self-healing occurs both within the polymer and at the polymer-cement interface, and (c) fibers that inhibit crack propagation, thus allowing autogenous healing mechanisms to be more effective. In all cases, we discuss the self-healing agent and synthesize the state of knowledge on the self-healing mechanism(s). In this review article, the state of computational modeling across nano- to macroscales developed based on experimental data is presented for each self-healing approach. We conclude the review by noting that, although autogenous reactions help repair small cracks, the most fruitful opportunities lay within design strategies for additional components that can migrate into cracks and initiate chemistries that retard crack propagation and generate repair of the cement matrix.

Unsaturated Polyester Resin Filled with Cementitious Materials: A Comprehensive Study of Filler Loading Impact on Mechanical Properties, Microstructure, and Water Absorption.

In recent years, cheaply available cementitious materials (CMs) are increasingly finding useful applications in construction engineering. This manuscript focused on the development and fabrication of unsaturated polyester resin (UPR)/cementitious material composites to be potentially useful in a variety of construction applications. For this purpose, five types of powders from widely available fillers, i.e., black cement (BC), white cement (WC), plaster of Paris (POP), sand (S), and pit sand (PS), were used. Cement polymer composite (CPC) specimens were prepared by a conventional casting process with various filler contents of 10, 20, 30, and 40 wt %. Neat UPR and CPCs were investigated mechanically by testing their tensile, flexural, compressive, and impact properties. Electron microscopy analysis was used to analyze the relation between the microstructure and mechanical properties of CPCs. The assessment of water absorption was conducted. The highest tensile, flexural, compressive upper yield, and impact strength values were recorded for POP/UPR-10, WC/UPR-10, WC/UPR-40, and POP/UPR-20, respectively. The highest percentages of water absorption were found to be 6.202 and 5.07% for UPR/BC-10 and UPR/BC-20, while the lowest percentages were found to be 1.76 and 1.84% for UPR/S-10 and UPR/S-20, respectively. Based on the finding of this study, the properties of CPCs were found to depend on not only the filler content but also the distribution, particle size, and combination between the filler and the polymer.

Porous polymer cement composites for quasi-solid graphene supercapacitors

We reported a strong and cheap polymer modified Portland cement (PC) composites with interconnected pores as solid electrolyte for graphene supercapacitors. The porous polymer cement composites solved the low ionic conductivity question of construction materials. Herein, the effects of PAA molecular weight, PAA content and curing age on electrical energy storage and mechanical property were investigated in detail. The PAA (Mw = 5000)/PC-5 % sample delivers the best multifunctionality. Moreover, the as-assembled solid supercapacitor exhibits an optimum energy density of 15.93 mW h cm−2, as well as a considerable compressive strength of 16.2 MPa at 28 days. In addition, introducing PAA can result in high porosity which is conductive to ion migration. The symmetric electrode is directly loaded with GO on Ni foam by electrophoretic, followed by high temperature thermal reduction. The integrated solid supercapacitors are effective, holistic and effortless to operate at room temperature, and they exert a crucial role in energy storage field of inorganic building materials application.

Piezo-resistive Properties of Polymer based cement nano composites

The nano technology has potential applications in development self-sensing smart materials. These nano materials is used in cement matrix or polymer base to improve the mechanical and piezo electrical properties of composites. In the present study, the graphene and carbon nano tube are added in matric, which acts as the conductive fibre into polymer cement composites. Cement based polymer composites are prepared by adding carbon fibre, epoxy resin, carbon nano tube and graphene as conductive filler in matrix to prepare the distinctive specimens for experimental investigations. The electro mechanical test are carried out to assess the piezo electrical properties of these composites subjected gradual increase of mechanical loading such as flexural and compression. The present study describes the self-sensing piezo-resistive capability of composite to monitor the strain in structures. The experimental test elucidates the addition of epoxy in cement matrix enhance the mechanical properties while carbon nano tube and graphene proves to be promising smart self-sensing materials in composites by measuring the variation in stress at critical regions. The SEM with EDX analysis shows that epoxy resin act as binding agent which hinder the cracks propagations and improves the mechanical properties of composites.

Corrosion initiation and its effect on bond characteristics and service life of reinforced concrete systems with Cement-Polymer-Composite coated steel rebars

This paper investigates the corrosion and bond characteristics of steel reinforcement with Cement-Polymer-Composite (CPC) coating, which is widely used worldwide to prolong the initiation of corrosion. CPC coating is supposed to be applied on sandblasted or cleaned surface to exploit its full potential. However, CPC coating is generally applied on the rusted or uncleaned surface, which can lead to premature corrosion initiation and associated degradation of the bond between coated steel and concrete. For corrosion studies, 20 lollipop specimens with as-received and sandblasted steels, and with and without CPC coating were cast. These were exposed to chlorides and tested using a recently developed test method based on the linear polarization resistance technique. It was found that as-received, CPC coated steels had 50% less chloride threshold than sandblasted, CPC coated steel. For bond studies, 16 pull-out specimens with CPC coated steel rebars were cast. It was found that even negligible corrosion can lead to ≈50 to 70% reduction in bond strength. This indicates that the corrosion propagation period in the case of CPC coated rebar systems would be negligible. Based on the corrosion and bond results, a new service life model for RC systems with CPC coated steel rebars is proposed. The results highlight that if preventive maintenance is not employed, many structures with CPC coated rebars can experience premature corrosion initiation and significant bond reduction.

Enhancing the mechanical behaviour of concretes through polymer modification of the aggregate-cement paste interface

A critical obstacle to the design of polymer-cement composites is its relatively large contents required for a significant improvement on concrete performances, which increased materials cost and decreased compressive strength. In this study, an asphalt emulsion, waterborne epoxy resin, and waterborne epoxy resin modified asphalt emulsion were used to pretreat aggregates for improving the toughness of concrete at relatively low polymer contents. The results showed that, for the model aggregate concrete, the partial replacement of polymer-coated aggregates could induce cracks and yielded better improvement in concrete toughness as compared to full replacement. However, the three-point bending tests showed the opposite results, compared with partial replacement, complete replacement of polymer coated aggregate increases the fracture energy which can be attributed to the interlocking effect of the gravel aggregate. The addition of water-based epoxy resin-asphalt emulsion composite emulsion showed the best improvement on concrete toughness. With 30% composite emulsion coated aggregate, concrete showed almost the same strength with 33% increase in concrete fracture energy. With 100% composite emulsion coated aggregate, concrete showed about 11.5% decrease in compressive strength, but 73.4% increase in concrete fracture energy. Increasing the polymer film thickness on the aggregate surface could significantly increase the energy consumption during the fracture process of concrete and improve its toughness.

Effect of temperature on the properties of polymer cement composite material

AbstractIn the actual working environment for the polymer cement composite, the effect of temperature on its properties cannot be ignored. In order to investigate the properties of polymer cement composite in extreme temperature environment, this study conducted bond test, tensile test, and shear test of composites at different temperatures (−30, −15, 25, 40, and 60°C). Through measuring the elastic recovery rate of specimens, as well as relevant strength indexes, deformation indexes and energy consumption indexes under tensile and shear loads, the effect of temperature on the bond property, tensile property, and shear property of the composite were investigated. The results show that the polymer cement composite has a good bond property, and no damage occurs at any temperature or after cold drawing and hot pressing cycle. Temperature has a great influence on the tensile property and shear property of polymer cement composite. At a low temperature, the tensile property and shear property improve, the strength and energy consumption indexes increase noticeably, and the elongation at break increases while the peak strain reduces in terms of deformation indexes. At a high temperature, the tensile property and shear property deteriorate, and the strength, deformation, and energy consumption indexes all fall. As a result, the polymer cement composite is more suitable for cold areas.

Studies on the Microstructure of Epoxy-Cement Mortar

Introduction of polymers into the cement composites improves same of the properties of concretes and mortars. Therefore, the polymer-cement composites are successfully used in construction. The model of microstructure formation in cement composites modified with thermoplastic polymer (pre-mix modifiers) has already been developed and successfully implemented. However, the formation of microstructure in the case of epoxy-cement composites (containing post-mix modifier) demonstrates same peculiarities which should be taken into account when modelling the process. The microstructure of epoxy-cement composites and its formation is discussed in the paper. The model is offered, formulated on the basis of the microscopic observations and results of testing.

Study on the Effects of Powder-Liquid Ratio and Cement Ratio on Mechanical Properties and Microscopic Characteristics of Polymer-Cement Composite

This paper is about a study on the mechanical properties of a new polymer-cement composite (PCC) in constant elongation, tension, and shear. The study explored the effects of powder-liquid ratio and cement ratio on the mechanical properties of PCC through detecting the strength, deformation, and energy consumption of specimens under different powder-liquid ratios and cement ratios. In addition, scanning electron microscope and mercury injection apparatus were used for an in-depth analysis on the micromorphology and pore structure features of PCC under different powder-liquid ratios and cement ratios to explore the influence of powder-liquid ratio and cement ratio of the micromechanical properties of PCC. The results showed that, with the increase of powder-liquid ratio and cement ratio, the constant elongation adhesion strength of PCC decreased, and, at a high powder-liquid ratio (0.55) or a high cement ratio (0.5), the constant elongation adhesion strength of PCC completely disappeared. Meanwhile, with the increase of powder-liquid ratio and cement ratio, the tensile shear strength of PCC increased, while the deformation capacity of PCC decreased. The optimal ranges of powder-liquid ratio and cement ratio for PCC were 0.35–0.4 and 0.3-0.4, respectively. Furthermore, the increased powder-liquid ratio and cement ratio made the total pore volume decreased and pore structure refined, which improved the compactness of PCC, thus influencing the performance of PCC macroscopically. An achievement for the study is a flexible composite material, which was formulated with the polymer film as continuous base phase, as well as the inorganic composition and cement hydrates as dispersion phase. The material can effectively improve the economy and practicability of cementation of fissures for airfield pavement.

Flexural strength enhancement of cement paste through monomer incorporation and in situ bond formation

Polymer-cement composites produced by physical mixing are limited by their relatively low compressive strengths and weak interfacial bonding between two dissimilar phases. These limitations can be addressed by effectively inhibiting the aggregation of polymer chains. Herein, a series of cement/ polyacrylamide (PAM) composites is fabricated through the situ polymerization of acrylamide (AM) monomers during the early hydration stage of cement. In the designed composite, the polymer chemically interacts with cement hydration products and exhibits a randomly stretched distribution. The in situ polymerization of 1% well-dispersed monomers increases the flexural strength of the cement composite from 8.5 to 25.7 MPa, while maintaining its compressive strength. Compared with the polymer-cement paste obtained by adding 1% neat PAM, the designed composite attains a 53% and 26% improvement in flexural strength and compressive strength, respectively. This strategy is highly desirable for wide application of tough cementitious materials and provides insight into organic/inorganic composite designing.

The Influence of Cement Substitution by Biomass Fly Ash on the Polymer-Cement Composites Properties.

The generation of energy for the needs of the population is currently a problem. In consideration of that, the biomass combustion process has started to be implemented as a new source of energy. The dynamic increase in the use of biomass for energy generation also resulted in the formation of waste in the form of fly ash. This paper presents an efficient way to manage this troublesome material in the polymer–cement composites (PCC), which have investigated to a lesser extent. The research outlined in this article consists of the characterization of biomass fly ash (BFA) as well as PCC containing this waste. The characteristics of PCC with BFA after 3, 7, 14, and 28 days of curing were analyzed. Our main findings are that biomass fly ash is suitable as a mineral additive in polymer–cement composites. The most interesting result is that the addition of biomass fly ash did not affect the rheological properties of the polymer–cement mortars, but it especially influenced its compressive strength. Most importantly, our findings can help prevent this byproduct from being placed in landfills, prevent the mining of new raw materials, and promote the manufacture of durable building materials.

Polymer-Cement Composites Glazing by Concentrated Solar Energy

Macro defect free (MDF) cements are polymer-cement composites characterized by high biaxial flexural strength compared to traditional concrete, having as a drawback a low water resistance. Glazing these composite materials with an inorganic enamel containing TiO2 nano-particles has led to a high water-stable material with advanced photocatalytic properties. Classic glazing by thermal treatment of samples, at 1050 °C, requires energy consumption and long-time performing. The purpose of this paper is to test the use of solar radiation as a source of energy in the glazing process. A vertical axis solar furnace has been used, from PROMES-CNRS Solar Laboratory, Font-Romeu Odeillo, France, and it has been observed that a uniform appearance of the glaze coating has been achieved; it shows high scratch resistance, meaning a good hardness and adhesion to the substrate. The obtained film was also characterized by SEM, EDS and XRD, aiming to evidence the coat morphology, the TiO2 distribution and its crystallinity alteration, when compared to the samples obtained by classic thermal treatment. The conclusion of the paper is that using solar radiation in the MDF cement glazing process is a promising approach for obtaining multifunctional materials.

Effect of Ultraviolet Aging on the Bonding and Tensile Properties of Polymer-Cement Composite

In this paper, the specimens of polymer-cement composites after 1 d, 7 d, 15 d, and 30 d aging without aging and UV aging are subjected to fixed extension test and tensile test. By observing the mode of the composite in the fixed-elongation test, and measuring the elastic recovery rate, tensile strength, elongation at break, peak tensile strain, tensile toughness and pre-peak tensile toughness of the composite, the effects of UV aging on the bonding and the tensile properties of the composite were studied. And combining with scanning electron microscopy experiments, the micro-mechanism of the effect of ultraviolet aging on the properties of composite was analyzed. The results showed that the composite had a good bonding property, and no damage was observed after UV aging for 30 days. The UV aging increased the elastic recovery rate and peak tensile within a certain range. The elastic recovery rate and peak tensile strain of the composite increased by 6.60% and 23.55% respectively after UV aging for 15 days. Therefore, the UV aging could enhance the tensile property and the tensile energy consumption performance of the composite. The tensile strength of the composite increased by 65.36% after UV aging for 30 days. The tensile toughness and pre-peak tensile toughness of the composite were increased by 43.29% and 101.83% respectively after UV aging for 15 days. The elongation at break of composite decreased continuously after UV aging due to the photo-oxygen reaction, as well as secondary hydration reaction and cross-linking curing reaction of cement.