Polymer Cement Research Articles

Redispersible Acrylic Ester Polymers: Effect of Polymer Property Changes Due to Polymerization Method Modification and Functional Additives on the Performance of Polymer Cement Mortar

This paper presents an experimental study aimed at improving the performance of polymer cement mortar by evaluating the properties of acrylic ester redispersible polymers, synthesized using a change in polymerization method from emulsion monomer to monomer dropwise addition methods, along with the use of a functional additive in the form of a foaming agent. To achieve the research objectives, a polymer with a glass transition temperature of −11 °C was synthesized by fixing the monomer ratio, particle-size distribution, and glass transition temperature, and the physical properties of the polymer cement mortar were assessed. The results showed that polymers synthesized using the modified polymerization method increased elongation at break and possessed a 35% smaller average particle size. The use of the foaming agent also resulted in enhanced tensile strength. The polymer cement mortars made with these respective polymers demonstrated improvements in compressive strength 11~25%, flexural strength 53~77%, bond strength 78~113%, volumetric changes 65~88%, and water absorption 30~70%. These findings suggest that changes in the polymerization method and the incorporation of functional additives influence the average particle size and air entrainment control properties of the polymers, thereby positively impacting the performance of the cement hydrates.

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

Study on Flexural Performance of Reinforced Concrete Beams Strengthened with FRP Grid–PCM Composite Reinforcement

To study the flexural performance of fiber-reinforced polymer (FRP) grid–polymer cement mortar (PCM)-composite-strengthened RC beams, the finite element numerical simulation of FRP grid–PCM composite RC beams is carried out using ABAQUS to analyze the effects of the amount of FRP grid reinforcement, the type of FRP grid material, and the geometry of FRP grid on the flexural performance of reinforced concrete beams and to establish the flexural capacity calculation formula of FRP grid–PCM-reinforced RC beams in case of debonding failure, based on analysis of the influencing factors. The results show that increasing the reinforcement of the FRP grid and increasing the stiffness of the FRP grid can improve the flexural bearing capacity of RC beams, and the change of FRP grid geometry has little effect on the flexural bearing capacity of RC beams. The established formula for calculating the flexural bearing capacity of FRP grid-reinforced concrete beams can better predict the flexural capacity of reinforced concrete beams under peeling failure.

The research progress and Hotspot analysis of polymer cement mortar based on bibliometrics

Ordinary cement mortar is commonly used in building engineering due to its high strength, affordability, and easy access to raw materials. However, it suffers from high shrinkage and poor impermeability, which result in reduced building service life and significant carbon dioxide emissions during production. Polymer additives have been found to enhance the mechanical properties of cement mortar, leading to increased interest in polymer cement mortar by researchers. This study collected and analyzed 420 papers published between 1995 and 2023 in the field of polymer cement mortar. The analysis included publication trends, author cooperation networks, national cooperation networks, published journals, co-citation of references, and keywords. The findings reveal a rapid publication growth from 2018 to 2023, with China making the most significant contribution in this field. Among the scholars, Ru Wang has published the highest number of articles in the field of polymer cement mortar, while Ohama’s papers have been cited the most. The journal with the most articles is Construction and Building Materials. Research in polymer cement mortar focuses on mechanical properties, performance, hydration process, microstructure, and other related aspects. The reinforcement effect of polymer-modified cement mortar on reinforced concrete and applying superabsorbent polymer-modified cement mortar and polymer fiber in cement mortar have emerged as recent research frontiers. This study can help scholars quickly identify high-quality references and research frontiers in the field of polymer cement mortar while also providing research directions and ideas.

Study on the influence of wedge-shaped steel plate hoops and steel strands wire mesh-PCM on seismic performance of damaged RC columns

This paper presents an experimental investigation on the use of polymer cement mortar (PCM) and steel strands wire mesh (SSWM) for strengthening damaged reinforced concrete (RC) columns. A new type of anchor device, wedge-shaped steel plate hoops (WSSPHs), was developed to maximize the resistance of the steel strands. The study aimed to analyze the impact of spacing and prestressing level on the mechanical properties of the damaged RC columns. Six columns were constructed and tested under low-cycle reciprocating quasi-static tests, including three control columns and three strengthened columns. The research focuses on the strengthening mechanism of WSSPHs and explores the influence of steel strand prestressing level and spacing on factors such as failure modes, hysteresis behavior, stiffness degradation, and cumulative energy dissipation of the strengthened columns. The test results showed that while the strength and stiffness of the strengthened specimens were not fully restored due to significant damage, the ductility and energy dissipation of the columns were improved. Moreover, columns with higher steel strand prestressing levels and narrower spacing demonstrated better strengthening effects. The study assessed the level of damage in specimens using the Park-Ang model, confirming the effectiveness of the proposed strengthening method.

Numerical analysis of reinforced concrete beams enhanced in shear with external polymer cement mortar‐bonded FRP grid

AbstractThis paper presents a finite element (FE) modeling approach to assess the performance of reinforced concrete (RC) beams strengthened in shear using external polymer cement mortar (PCM)‐bonded basalt fiber‐reinforced polymer (BFRP) grids. The study begins with an experimental program and FE modeling of a double shear bond test, simulating the bond behavior between the BFRP grid and RC beams with PCM. Subsequently, a FE model for BFRP shear‐strengthened beams explores key parameters, including shear span to depth ratio, bonding agent type (PCM and epoxy resin), and angles between BFRP grid bars and the beam axis. Comparative analysis with experimental results verifies the accuracy of the FE models. Additionally, a critical parameter, the BFRP reinforcement ratio, is numerically investigated, revealing that achieving a ratio between 1.33% and 1.55% enhances both maximum load and deflection in beams strengthened with externally bonded composite reinforced mortar.

Improving bonding performance of PCM-concrete interface under elevated temperatures by using different adhesives

Polymer cement mortar (PCM) has been widely utilized in engineering practice for the repair and strengthening of damaged concrete. However, the bond strength of PCM-concrete interface can deteriorate under high temperatures. To enhance bonding performance, a new interface treatment method needs to be explored. This study aimed to investigate the bond performance between concrete and PCM after adding a layer of epoxy bonding agent (EP) or carbon fiber-reinforced polymer (CFRP) to the interface, as well as to investigate the effect of temperature. The bond behavior was evaluated by interfacial split tensile tests. The experimental results show that the splitting tensile strength of the specimens decreased as the temperature increased. After being exposed to a temperature of 100 °C, the splitting tensile strength of specimens without interface reinforcement, EP- and CFRP-reinforced interface specimens decreased by 35.42%, 58.90%, and 63.39%, respectively. When the ambient temperature exceeds 80 °C, bonding with epoxy or CFRP does not improve the bond performance due to the decomposition of epoxy. Finally, the relationship between the splitting tensile strength of the three types of specimens and temperature was clarified, and a model was developed to predict the strength degradation under elevated temperatures. The results are useful for improving the durability and safety of concrete structures repaired with PCM.

Influence of surface roughness and interfacial agent on the interface bonding characteristics of polyurethane concrete and cement concrete

As a new type of concrete material, polyurethane concrete has excellent physical and mechanical properties which is widely used in the maintenance and reinforcement of damaged areas of concrete pavement. Because of the difference in the performance between polymer concrete and ordinary concrete, it is of great significance to accurately evaluate the bond performance between polymer concrete and ordinary concrete in order to avoid interface damage in the subsequent use of the repaired pavement. In this study, the bonding specimens were made by changing the roughness and interfacial agent of the bonding interface between polymer concrete and cement concrete, and splitting tensile test and direct shear test were carried out to explore the bond properties between them. Polymer concrete-cement concrete composite beam specimens were made to simulate the maintenance and reinforcement of cement concrete pavements with polymer concrete in the actual projects, and the flexural performance test was carried out to explore the common mechanical characteristics of bonding specimens. The test results showed that the bond performance of polymer concrete and cement concrete was closely related to the interface roughness and the interfacial agents, and the addition of polymer concrete improves the common stress characteristic of composite beam specimens. The test results provide a basis for polymer concrete as a rapid repair material for concrete pavement repair.

Mechanical properties of polymer modified mortars using polymer latexes with varied glass transition temperature and surface charges

Mechanical properties of polymer modified mortar (PMM) were investigated using self-synthesized polymer latexes with varied glass transition temperature (Tg) and colloidal surface charges to build correlations between the mechanical properties of PMMs and the intrinsic properties of the polymers. Generally, compressive strength and elastic modulus of mortar are decreased, but ductility and toughness are enhanced by incorporation of the polymers. Impacts of the lower Tg polymers on the mechanical properties of PMMs are more pronounced. With increasing polymer content, flexural and tensile strength of mortar first increase and then decrease when using low Tg polymers that form continuous film during hardening of the mortars, while steadily decrease in the case of high Tg polymers that exist as individual particles in the hardened PMMs. For the high Tg polymer modified mortars, it is interestingly found that a subsequential heat treatment effectively promotes the film formation of the polymers in the hardened PMMs and thus greatly increases their flexural and tensile strength. This indicates that polymer film formation is essential to the enhancement of the PMMs, because the polymer films play a crack-bridging effect while the individual particles cannot do such job. The high Tg polymers lead to higher tensile strength of PMMs after heat treatment due to the higher inherent strength of the polymer film. Higher colloidal surface charge benefits the mechanical properties of the PMMs by (1) promoting a more homogenous polymer distribution in the hardened PMMs and/or (2) improving the bonding between the polymer phase and cement hydrates.

Information fusion-based maintenance strategies selection for coastal concrete bridges using recycled fishing nets

Repurposing recycled materials for coastal concrete bridge maintenance addresses both engineering requirements and marine ecosystem preservation. This study explored the application of recycled nylon (RN) and polyethylene (PE) from discarded fishing nets in coastal concrete beam maintenance. Specifically, these fibers were incorporated into the polymer cement mortar (PCM) to produce two repair materials. Then, thirteen unrepaired or preventive/post-repaired concrete beams were exposed to the tidal zone for one or two years, followed by beam bending tests and the establishment of the corresponding parametric Finite element modeling (FEM). As an alternative to traditional heavy-parameter models, a novel lightweight crack segmentation model (LiteSqueezeSeg) was proposed for quantitatively analyzing beam surface crack properties. Lastly, experimental, simulated, and quantitative crack information were fused to comprehensively assess the beam performance. Results showed that both PCM-RN and PCM-PE effectively inhibit chloride ion penetration. The proposed LiteSqueezeSeg model (95.66% accuracy) achieved nearly identical performance to Deeplab v3 + but only with about 1/6 parameters. Fused results revealed that PCM-PE repaired beams exhibited superior mechanical performance but inferior ductility compared to PCM-RN. Moreover, both PCM-PE and PCM-RN repaired beams demonstrated that preventive repairs achieved more balanced performance than post repairs. Consequently, utilizing PCM-RN for preventive repair emerged as an optimal candidate. This study significantly contributes to the utilization of waste fishing nets in coastal concrete structure maintenance.

Influence of Thermal and Chemical Stresses on Thermal Properties, Crystal Morphology, and Mechanical Strength Development of a Sulfur Polymer Composite

The unique properties and sustainability advantages of sulfur polymer cement have led to efforts to use them as alternatives to traditional Portland cement. The current study explores the impact of environmental stresses on the strength development of polymer composite SunBG90, a material composed of animal and plant fats/oils vulcanized with 90 wt. % sulfur. The environmental stresses investigated include low temperature (−25 °C), high temperature (40 °C), and submersion in water, hexanes, or aqueous solutions containing strong electrolyte, strong acid, or strong base. Samples were analyzed for the extent to which exposure to these stresses influenced the thermo-morphological properties and the compressional strength of the materials compared to identical materials allowed to develop strength at room temperature. Differential scanning calorimetry (DSC) analysis revealed distinct thermos-morphological transitions in stressed samples and the notable formation of metastable γ-sulfur in hexane-exposed specimens. Powder X-ray diffraction confirmed that the crystalline domains identified by DSC were primarily γ-sulfur, with ~5% contribution of γ-sulfur in hexane-exposed samples. Compressive strength testing revealed high strength retention other than aging at elevated temperatures, which led to ~50% loss of strength. These findings reveal influences on the strength development of SunBG90, lending important insight into possible use as an alternative to OPC.

Injectable bioactive poly(propylene fumarate) and polycaprolactone based click chemistry bone cement for spinal fusion in rabbits.

Degenerative spinal pathology is a widespread medical issue, and spine fusion surgeries are frequently performed. In this study, we fabricated an injectable bioactive click chemistry polymer cement for use in spinal fusion and bone regrowth. Taking advantages of the bioorthogonal click reaction, this cement can be crosslinked by itself eliminating the addition of a toxic initiator or catalyst, nor any external energy sources like UV light or heat. Furthermore, nano-hydroxyapatite (nHA) and microspheres carrying recombinant human bone morphogenetic protein-2 (rhBMP-2) and recombinant human vascular endothelial growth factor (rhVEGF) were used to make the cement bioactive for vascular induction and osteointegration. After implantation into a rabbit posterolateral spinal fusion (PLF) model, the cement showed excellent induction of new bone formation and bridging bone, achieving results comparable to autograft control. This is largely due to the osteogenic properties of nano-hydroxyapatite (nHA) and the released rhBMP-2 and rhVEGF growth factors. Since the availability of autograft sources is limited in clinical settings, this injectable bioactive click chemistry cement may be a promising alternative for spine fusion applications in addressing various spinal conditions.

Priority of the effects of interface bonding and porosity on the energy storage capacity of structural supercapacitors

Both interface bonding between the electrodes and the electrolytes and the porosity in structural electrolytes have a great effect on the energy storage capacity of structural supercapacitors (SSC). To verify the priority of the two factors on the energy storage capacity of SSC, HP-CSA expansion agent (HP-CSA) was introduced to enhance the interface bonding of SSC. The results show that the introduction of HP-CSA can enhance the interface bonding of SSC, but decrease the porosity of the electrolyte. After introducing 3 wt % HP-CSA to the polymer cement electrolyte (PCE), the areal capacitance of the SSC increased by 79.93% than that of the SSC based on PCE-0. Moreover, its energy density increased by 79.85% compared with the SSC based on PCE-0. Therefore, the interface bonding of SSC has a greater effect on its energy storage capacity than the porosity in structural electrolytes. This work provides a direction for improving the energy storage capacity of SSC in the future.

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.

Bioactive Moldable Click Chemistry Polymer Cement with Nano-Hydroxyapatite and Growth Factor-Enhanced Posterolateral Spinal Fusion in a Rabbit Model.

Spinal injuries or diseases necessitate effective fusion solutions, and common clinical approaches involve autografts, allografts, and various bone matrix products, each with limitations. To address these challenges, we developed an innovative moldable click chemistry polymer cement that can be shaped by hand and self-cross-linked in situ for spinal fusion. This self-cross-linking cement, enabled by the bioorthogonal click reaction, excludes the need for toxic initiators or external energy sources. The bioactivity of the cement was promoted by incorporating nanohydroxyapatite and microspheres loaded with recombinant human bone morphogenetic protein-2 and vascular endothelial growth factor, fostering vascular induction and osteointegration. The release kinetics of growth factors, mechanical properties of the cement, and the ability of the scaffold to support in vitro cell proliferation and differentiation were evaluated. In a rabbit posterolateral spinal fusion model, the moldable cement exhibited remarkable induction of bone regeneration and effective bridging of spine vertebral bodies. This bioactive moldable click polymer cement therefore presents a promising biomaterial for spinal fusion augmentation, offering advantages in safety, ease of application, and enhanced bone regrowth.

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.

Experimental study of polyurethane cement composite–reinforced soft soil in the thawed layer in permafrost regions

Permafrost degradation induces a large number of thawed layers that have high water content, low bearing capacity, and high compressibility, which threaten the stability of infrastructure in permafrost regions. How to reinforce the soft layers of thawed permafrost is very essential for maintaining and repairing such infrastructure. This study investigates the reinforcement effect and mechanism of a polyurethane cement composite (PUC) on the soft soil in the thawed layer (SSTL) of permafrost through mechanical and microscopic tests. The experimental results indicate that the unconfined compressive strength (UCS) of the SSLT initially increases and then decreases with increasing hydrophilic polyurethane (WPU) content, while it increases with higher polymer cement content (PMC). The UCS of the SSLT reinforced with 10% WPU increases by 41.96% and 18.75% in the early and late stages, respectively, compared to a SSLT sample without added WPU at a moisture content of 40%, while the cohesion of the SSLT increases by 7.74%, and the internal friction angle increases by 29.48%. A microscopic analysis reveals that the PUC significantly enhances the microstructure of the SSLT through intricate physical and chemical reactions. PUC-reinforced SSLT provides a new way to address the settlement and deformation that adversely affect subgrade in permafrost regions.

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.

Improving the composite-structured supercapacitor assembled with Ni–Co-layered double hydroxide and polymer cement electrolyte through structural optimization

The optimized nickel–cobalt double hydroxide electrode by electrodeposition has a high specific area capacitance of 10.53 F cm−2. Capacitors assembled using the optimized electrodes have a specific capacitance of up to 1.442 F cm−2.

System "dispersed polyvinyl acetate-calcium silicate" in furnishing materials

This article focuses on the processes of interaction between calcium silicate hydrates and dispersed polyvinyl acetate in tight films with the aim of developing compounds meant for restoration and finishing works. The basis of this development relies on the concept concerning the determining role of the crystal-chemical factor of the silicate phase in the formation of organic-mineral compounds of increased durability. The characteristics of dispersed calcium silicate hydrates are portrayed. The preparation conditions, accounting for the synthesis of the product of submicrocrystalline structure, conforming with the stoichiometry CaO:SiO2=0.8-2.0 have been determined. The interaction has been studied for compounds achieved by mixing ingredients in a rapid whirling mixer, and subjected to hardening at T=20+2 °C. With the aid of XRD, DTA and Infra-Red Spectrometry methods the formation process of the sophisticated polymer silicate phase in the material was observed for a period of 90 days. The properties of the film were investigated and its high resistance against the influence of external factors was established. On this basis a conclusion concerning the quite high effectiveness of substituting portland cement with dispersed calcium silicate hydrate in polymer cement compounds has been made White colour and other various special properties determine the suitability for repair and finishing works on facades of buildings.