Research

16 pages, 5385 KiB

Open AccessArticle

Structural Performance of Lightweight Aggregate Concrete Reinforced by Glass or Basalt Fiber Reinforced Polymer Bars

by Mohammed A. Abed, Aysha Anagreh, Nikola Tošić, Ola Alkhabbaz, Majd Eddin Alshwaiki and Robert Černý

Polymers 2022, 14(11), 2142; https://doi.org/10.3390/polym14112142 - 24 May 2022

Cited by 7 | Viewed by 2625

Abstract

Lightweight aggregate concrete (LWC) and fiber reinforced polymer (FRP) reinforcement are potentially more sustainable alternatives to traditional steel-reinforced concrete structures, offering several important benefits. To further the knowledge in this area, the physical–mechanical properties of LWC produced with 0%, 50%, and 100% expanded [...] Read more.

Lightweight aggregate concrete (LWC) and fiber reinforced polymer (FRP) reinforcement are potentially more sustainable alternatives to traditional steel-reinforced concrete structures, offering several important benefits. To further the knowledge in this area, the physical–mechanical properties of LWC produced with 0%, 50%, and 100% expanded clay aggregate were assessed. Subsequently, the flexural behavior of LWC beams reinforced with steel reinforcement and glass and basalt FRP bars was tested. The results of the experimental program allowed quantifying of the effect of expanded clay aggregate incorporation on LWC properties. The use of FRP reinforcement was also compared to steel-reinforced concrete beam behavior. The results of this study can provide additional support for the use of innovative materials such as LWA and FRP reinforcement. Full article

(This article belongs to the Special Issue Application of Polymeric Materials in the Building Industry)

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15 pages, 7495 KiB

Open AccessArticle

Effect of Addition of Polyurea as an Aggregate in Mortars: Analysis of Microstructure and Strength

by Hernan Chacon, Heidis Cano, Joaquin Hernández Fernández, Yoleima Guerra, Esneyder Puello-Polo, John Fredy Ríos-Rojas and Yolima Ruiz

Polymers 2022, 14(9), 1753; https://doi.org/10.3390/polym14091753 - 26 Apr 2022

Cited by 11 | Viewed by 1947

Abstract

The addition of polymers in construction is a new tendency and an important step toward the production of structures with better functional properties. This work investigates the addition of polyurea (PU) as a polymeric material in mortars. Polymer mortars were manufactured with the [...] Read more.

The addition of polymers in construction is a new tendency and an important step toward the production of structures with better functional properties. This work investigates the addition of polyurea (PU) as a polymeric material in mortars. Polymer mortars were manufactured with the addition of polyurea retained in different sieves (T50 and T100) and different concentrations (2% and 5%). The characterization of the, polyurea (PU)control mortar (PU0%) and manufactured polyurea mortars (PU2%T50, PU5%T50, PU2%T100, and PU5%T100) was conducted by means of morphological analysis, SEM, XRF, TGA, and a compressive strength test of hydraulic mortars. The results show that mortars with polyurea retained in sieve 100 with a particle size of 150 μm exhibit better thermal behavior and a greater resistance to compression with a concentration of 5% polyurea with respect to the other samples. The present work reveals that polyurea retained in sieve 100 can be considered as a polymeric additive for mortars, indicating that it could be a candidate for applications such as construction. Full article

(This article belongs to the Special Issue Application of Polymeric Materials in the Building Industry)

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19 pages, 8529 KiB

Open AccessArticle

Multiscale Thermal Investigations of Graphite Doped Polystyrene Thermal Insulation

by Ákos Lakatos and Attila Csík

Polymers 2022, 14(8), 1606; https://doi.org/10.3390/polym14081606 - 14 Apr 2022

Cited by 8 | Viewed by 2319

Abstract

Nowadays, to improve quality of life, to have a more comfortable life, in internal spaces we try to maintain conditions that are free from external environmental influences. Thus, existing as well as newly built houses have adequate interiors maintaining their temperature, warming, or [...] Read more.

Nowadays, to improve quality of life, to have a more comfortable life, in internal spaces we try to maintain conditions that are free from external environmental influences. Thus, existing as well as newly built houses have adequate interiors maintaining their temperature, warming, or cooling due to the environment compensation. One way to create this is to reduce the heat loss in buildings. An option to achieve this is the application of thermal insulations. Nowadays, the use of super insulation materials such as aerogel and vacuum insulation panels and other nano-structured insulations, such as graphite doped expanded polystyrene, is becoming increasingly justified. These are relatively new materials, and we know only a little about them. This paper presents research results based on temperature-induced investigations of nanostructured graphite expanded polystyrene, to reveal its thermal stability after long-term and short-term thermal annealing, simulating the ageing of the material. Firstly, with a differential scanning calorimeter, we will explore the thermal stability profile of the specimens. After this, the paper will present temperature-induced changes in both the thermal properties and the structure of the samples. We will also present changes in the thermal conductivity, modifications in the surface, and compressive property variation induced by thermal annealing. The samples were thermal annealed at 70 °C for 6 weeks, at 100 and 110 °C for 1 h. Besides the thermal conductivity measurements with Netzsch 446 heat flow meter equipment, we will present specific heat capacity measurement results executed with the same equipment. Moreover, sorption isotherms of the as-received and annealed samples were registered and completed with hydrophobic experiments, too. Furthermore, from the measurements, we showed that temperature should affect a significant change in the thermal conductivity of materials. Moreover, the changes in the graphite expanded polystyrene before and after thermal annealing were investigated by Scanning Electron Microscopy, as well as optical microscopy. The structural changes were further followed by an X-ray diffractometer and the IR absorption capability was tested, too. Full article

(This article belongs to the Special Issue Application of Polymeric Materials in the Building Industry)

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40 pages, 14931 KiB

Open AccessArticle

Forecasting the Mechanical Properties of Plastic Concrete Employing Experimental Data Using Machine Learning Algorithms: DT, MLPNN, SVM, and RF

by Afnan Nafees, Sherbaz Khan, Muhammad Faisal Javed, Raid Alrowais, Abdeliazim Mustafa Mohamed, Abdullah Mohamed and Nikolai Ivanovic Vatin

Polymers 2022, 14(8), 1583; https://doi.org/10.3390/polym14081583 - 13 Apr 2022

Cited by 52 | Viewed by 3043

Abstract

Increased population necessitates an expansion of infrastructure and urbanization, resulting in growth in the construction industry. A rise in population also results in an increased plastic waste, globally. Recycling plastic waste is a global concern. Utilization of plastic waste in concrete can be [...] Read more.

Increased population necessitates an expansion of infrastructure and urbanization, resulting in growth in the construction industry. A rise in population also results in an increased plastic waste, globally. Recycling plastic waste is a global concern. Utilization of plastic waste in concrete can be an optimal solution from recycling perspective in construction industry. As environmental issues continue to grow, the development of predictive machine learning models is critical. Thus, this study aims to create modelling tools for estimating the compressive and tensile strengths of plastic concrete. For predicting the strength of concrete produced with plastic waste, this research integrates machine learning algorithms (individual and ensemble techniques), including bagging and adaptive boosting by including weak learners. For predicting the mechanical properties, 80 cylinders for compressive strength and 80 cylinders for split tensile strength were casted and tested with varying percentages of irradiated plastic waste, either as of cement or fine aggregate replacement. In addition, a thorough and reliable database, including 320 compressive strength tests and 320 split tensile strength tests, was generated from existing literature. Individual, bagging and adaptive boosting models of decision tree, multilayer perceptron neural network, and support vector machines were developed and compared with modified learner model of random forest. The results implied that individual model response was enriched by utilizing bagging and boosting learners. A random forest with a modified learner algorithm provided the robust performance of the models with coefficient correlation of 0.932 for compressive strength and 0.86 for split tensile strength with the least errors. Sensitivity analyses showed that tensile strength models were least sensitive to water and coarse aggregates, while cement, silica fume, coarse aggregate, and age have a substantial effect on compressive strength models. To minimize overfitting errors and corroborate the generalized modelling result, a cross-validation K-Fold technique was used. Machine learning algorithms are used to predict mechanical properties of plastic concrete to promote sustainability in construction industry. Full article

(This article belongs to the Special Issue Application of Polymeric Materials in the Building Industry)

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16 pages, 5270 KiB

Open AccessArticle

Effects of Secondary Porosity on Microstructure and Mechanical Properties of SAP-Containing Lime-Based Plasters

by Jan Fořt, Martin Böhm, Igor Medveď, Martin Mildner and Robert Černý

Polymers 2022, 14(6), 1162; https://doi.org/10.3390/polym14061162 - 15 Mar 2022

Cited by 1 | Viewed by 2064

Abstract

Despite the many benefits associated with the utilization of superabsorbent polymers (SAPs), several drawbacks have been reported. In particular, the effect of SAPs on microstructure, together with its consequences for mechanical properties, is not fully understood yet for some composite materials. This study [...] Read more.

Despite the many benefits associated with the utilization of superabsorbent polymers (SAPs), several drawbacks have been reported. In particular, the effect of SAPs on microstructure, together with its consequences for mechanical properties, is not fully understood yet for some composite materials. This study analyzes the role of SAPs in the formation of the microstructure of lime composites, taking into account their chemical composition. The obtained experimental results show that the particle size and cross-linking density of used SAPs are crucial parameters affecting both the microstructure and mechanical performance of the analyzed composites. Coarser SAPs with low cross-linking density in the dosage of 0.5 and 1 wt.% are found as the most suitable solution, leading even to a slight improvement of mechanical parameters. The secondary porosity formed by swelled hydrogels is identified as a very significant factor since hydrogel-filled voids do not contribute to the strength parameters. The formation of the affected zone around SAP cores depends on the chemical composition of SAPs considerably as the higher cross-linking density influences the desorption rate. Based on achieved results, utilization of SAPs in building materials should be studied at a more detailed level with particular importance on the definition of SAP-related voids and affected zone around SAP particles. Full article

(This article belongs to the Special Issue Application of Polymeric Materials in the Building Industry)

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23 pages, 8017 KiB

Open AccessArticle

Enhancing the In-Plane Behavior of a Hybrid Timber Frame–Mud and Stone Infill Wall Using PP Band Mesh on One Side

by Yinlan Shen, Xingchen Yan, Hui Liu, Guofang Wu and Wei He

Polymers 2022, 14(4), 773; https://doi.org/10.3390/polym14040773 - 16 Feb 2022

Cited by 2 | Viewed by 2336

Abstract

Traditional village dwellings in China consisting of timber frames with mud and stone infill walls represent an important part of cultural heritage and civilization. Due to the lack of an effective link between the wood frame and the infill and the poor cohesiveness [...] Read more.

Traditional village dwellings in China consisting of timber frames with mud and stone infill walls represent an important part of cultural heritage and civilization. Due to the lack of an effective link between the wood frame and the infill and the poor cohesiveness of clay, the masonry infill can collapse during an earthquake, whereas the wood frame suffers minimal damage. In this study, current retrofitting techniques for village buildings were investigated and discussed. A method using polypropylene (PP) band mesh and cement mortar to retrofit the timber frame with a mud and stone infill was proposed and the connection construction details were designed. In-plane static cyclic tests were conducted on two full-scale wood–stone hybrid walls reinforced on one side with different grid sizes of the PP band mesh. The failure behaviors of the reinforced and non-reinforced sides of the specimens were compared, and the failure mechanics and seismic capacity of the two specimens, i.e., the strength, stiffness, ductility, and energy dissipation, were investigated. The results were also compared with those of a previous frame with stone infill without pebbles and no reinforcement. The study indicated that the retrofitting method strengthened the integrity and lateral resistance of the hybrid structure and prevented the collapse of the stone infill of the reinforced surface in a plane earthquake. The grid size of the PP band mesh substantially affected the lateral performance of the reinforced specimens. The hybrid wall with the narrow PP band mesh grid (150 mm × 150 mm) had a higher lateral stiffness (79%) and lateral capacity (50%) than the wall with the wide grid (250 mm × 250 mm). However, the narrow PP band mesh resulted in a lower ductility of the wall than the wide PP band mesh. The involvement of pebbles in the stone infill led to collapses sooner and a weaker lateral resistance than in the structure without pebble infill. Full article

(This article belongs to the Special Issue Application of Polymeric Materials in the Building Industry)

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21 pages, 8374 KiB

Open AccessArticle

Structural Behavior of RC Column Confined by FRP Sheet under Uniaxial and Biaxial Load

by Huynh-Xuan Tin, Ngo-Thanh Thuy and Soo-Yeon Seo

Polymers 2022, 14(1), 75; https://doi.org/10.3390/polym14010075 - 25 Dec 2021

Cited by 8 | Viewed by 3713

Abstract

Various researches have been performed to find an effective confining method using FRP sheet in order to improve the structural capacity of reinforced concrete column. However, most of these researches were undertaken for the columns subjected to concentric compressive load or fully confined [...] Read more.

Various researches have been performed to find an effective confining method using FRP sheet in order to improve the structural capacity of reinforced concrete column. However, most of these researches were undertaken for the columns subjected to concentric compressive load or fully confined RC columns. To date, it remains hard to find studies on partially FRP-confined RC columns under eccentric load. In this manner, an experimental investigation was carried out to assess the performance of rectangular RC column with different patterns of CFRP-wrap subject to eccentric loads in this paper. The experiment consists of fourteen mid-scale rectangular RC columns of 200 mm × 200 mm × 800 mm, including five controlled columns and nine CFRP-strengthened ones. All CFRP-strengthened columns were reinforced with one layer of vertical CFRP sheet with the main fiber along the axial axis at four sides, then divided into three groups according to confinement purpose, namely unconfined, partially CFRP-confined, and fully CFRP-confined group. Two loading conditions, namely uniaxially and biaxially eccentric loads, are considered as one of the test parameters. From the test of uniaxial eccentric load, partial and full CFRP-wraps provided 19% and 33% increased load-carrying capacity at an eccentricity-to-column thickness ratio (e/h) of 0.125, respectively, compared to controlled columns, and 8% and 11% at e/h = 0.25, respectively. For the partially CFRP-confined columns subjected to biaxial eccentric load with e/h = 0.125 and 0.25, the load-carrying capacities were improved by 19% and 31%, respectively. This means that the partial confinement with CFRP effectively improves the load-carrying capacity at larger biaxial eccentric load. It was found that the load-carrying capacity could be properly predicted by using code equations of ACI 440.2R-17 and Fib Bulletin 14 Guideline for the full CFRP-confined or partially CFRP-confined columns under uniaxial load. For partially CFRP-confined columns under biaxial loading, however, the safety factors using the Fib calculation process were 20% to 31% lower than that of uniaxially loaded columns. Full article

(This article belongs to the Special Issue Application of Polymeric Materials in the Building Industry)

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16 pages, 4783 KiB

Open AccessArticle

Waste Rubber from End-of-Life Tires in ‘Lean’ Asphalt Mixtures—A Laboratory and Field Investigation in the Arid Climate Region

by Stefano Marini and Michele Lanotte

Polymers 2021, 13(21), 3802; https://doi.org/10.3390/polym13213802 - 03 Nov 2021

Cited by 5 | Viewed by 1994

Abstract

Waste rubber from end-of-life tires has been proved to be an excellent source of polymeric material for paving applications. Over the years, however, the rubberized asphalt technology has never been used in ‘lean’ (low bitumen content) asphalt mixtures typically used in arid regions. [...] Read more.

Waste rubber from end-of-life tires has been proved to be an excellent source of polymeric material for paving applications. Over the years, however, the rubberized asphalt technology has never been used in ‘lean’ (low bitumen content) asphalt mixtures typically used in arid regions. This study offers an insight on the potential benefits and drawbacks resulting from this technology if applied in such ‘lean’ mixes. Results show that the ‘lean’ nature of those asphalt mixes eliminates the potential benefits given by the modified bitumen for rutting performance. Instead, the aggregates gradation plays a major role in the response of the materials, with gap-graded mixtures often outperforming those with a dense-graded gradation. On the contrary, fatigue cracking resistance is affected by the bitumen properties, and rubberized asphalt perform better than others. The performance-based analysis suggests that the current specifications tend to overachieve the goal of reducing permanent deformation while cracking becomes a major concern which can be solved by using rubberized asphalt. In the field, gap-graded asphalt with rubberized bitumen showed the best response in terms of skid resistance and noise reduction. Full article

(This article belongs to the Special Issue Application of Polymeric Materials in the Building Industry)

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17 pages, 6071 KiB

Open AccessArticle

Microstructure Formation of Cement Mortars Modified by Superabsorbent Polymers

by Jan Fořt, Jiří Šál, Martin Böhm, María Jesús Morales-Conde, Manuel Alejandro Pedreño-Rojas and Robert Černý

Polymers 2021, 13(20), 3584; https://doi.org/10.3390/polym13203584 - 18 Oct 2021

Cited by 2 | Viewed by 1783

Abstract

The utilization of superabsorbent polymers (SAPs) in cement-based materials has been found to be a promising means of mitigating the autogenous propagation of shrinkage and cracks. On the other hand, the undesired effects of SAPs’ application on functional properties, including mechanical strength, microstructure [...] Read more.

The utilization of superabsorbent polymers (SAPs) in cement-based materials has been found to be a promising means of mitigating the autogenous propagation of shrinkage and cracks. On the other hand, the undesired effects of SAPs’ application on functional properties, including mechanical strength, microstructure formation, and the evolution of hydration heat are not properly understood, given the variety in SAPs’ characteristics. To contribute to the present state-of-the-art, cement mortars, modified with two grades of SAPs by dosages of 0.3%, 0.6%, and 0.9%, were designed and studied with emphasis on the relationship between the materials’ porosities and mechanical strengths. The obtained results are interpreted by scanning electron microscopy analysis and hydration heat evolution to elucidate the major changes and their driving factors. Besides the benefits associated with the mitigation of autogenous shrinkage, the achieved results point to an adverse effect of supplementation with SAP on mechanical strength at an early age, and an even more pronounced increase at a later age. The employed scanning electron microscopy images, together with mercury-intrusion porosimetry data, depict distortion in the material porosity as a result of the filling of formed voids and the closing of open ends by swelled hydrogels. Only the minor benefit of a greater cross-linking density was obtained by the formation of dense structures and the gains in mechanical strength therefrom. Full article

(This article belongs to the Special Issue Application of Polymeric Materials in the Building Industry)

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17 pages, 3006 KiB

Open AccessArticle

Functional Properties of SAP-Based Humidity Control Plasters

by Jan Fořt, Magdaléna Doleželová, Václav Kočí and Robert Černý

Polymers 2021, 13(14), 2279; https://doi.org/10.3390/polym13142279 - 12 Jul 2021

Cited by 4 | Viewed by 2188

Abstract

The application of materials with high moisture storage capacity close to the interior surface presents a prospective passive method for improving indoor relative humidity conditions. In this paper, lime-cement plasters containing three different types of superabsorbent polymers (SAPs) in varying dosages are introduced [...] Read more.

The application of materials with high moisture storage capacity close to the interior surface presents a prospective passive method for improving indoor relative humidity conditions. In this paper, lime-cement plasters containing three different types of superabsorbent polymers (SAPs) in varying dosages are introduced and their mechanical, hygric, and thermal characteristics are analyzed in a relation to microstructure. The experimental results show a significant effect of both SAP amount and chemical composition on all functional properties of studied plasters. The incorporation of 1.5% of SAP may induce up to 2.5 better moisture buffering, thus significantly improving the passive humidity control capability. Considering overall functional parameters of SAP-modified plasters, the dosage of 1 wt.% can thus be viewed as a rational compromise between the moisture storage capability and mechanical properties. The obtained wide sets of parameters can be utilized directly as input data of computational models suitable for the assessment of the interior microclimate of residential and administrative buildings. Full article

(This article belongs to the Special Issue Application of Polymeric Materials in the Building Industry)

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16 pages, 2388 KiB

Open AccessArticle

Tuning the Adhesive Properties of Soy Protein Wood Adhesives with Different Coadjutant Polymers, Nanocellulose and Lignin

by Milan Podlena, Martin Böhm, Daniel Saloni, Guillermo Velarde and Carlos Salas

Polymers 2021, 13(12), 1972; https://doi.org/10.3390/polym13121972 - 15 Jun 2021

Cited by 16 | Viewed by 3686

Abstract

Commercial wood adhesives are based on products that contain formaldehyde; however, environmental and health concerns about formaldehyde emissions from wood products have influenced research and development efforts in order to find alternative, formaldehyde-free products for wood adhesives. In this work, different soy protein-based [...] Read more.

Commercial wood adhesives are based on products that contain formaldehyde; however, environmental and health concerns about formaldehyde emissions from wood products have influenced research and development efforts in order to find alternative, formaldehyde-free products for wood adhesives. In this work, different soy protein-based wood adhesives are proposed, and their performance is compared to commercial urea formaldehyde (UF) adhesive. Soy protein-based wood adhesives were prepared using either soy protein isolate (SPI) or soy protein flour (SF) with different coadjutant polymers: polyethylene oxide (PEO), hydroxypropyl methylcellulose (HPMC), cellulose nanofibrils (CNF) or polyvinyl alcohol (PVA) with and without addition of kraft lignin. The effects of the type of soy protein, solids content, coadjutant polymer and lignin addition were investigated. The wood adhesive formulations were tested on the bonding of hardwood (white maple) and softwood (southern yellow pine) and the dry shear strength of test specimens was measured according to method ASTM D905-08. The adhesive formulations with SPI achieved significantly higher values than those with SF. The dry shear strength of the adhesives varies depending on the coadjutant polymer, the wood species and the addition of lignin. Full article

(This article belongs to the Special Issue Application of Polymeric Materials in the Building Industry)

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18 pages, 2764 KiB

Open AccessArticle

Comparison of the Thermal Properties of Geopolymer and Modified Gypsum

by Karol Prałat, Justyna Ciemnicka, Artur Koper, Katarzyna Ewa Buczkowska and Piotr Łoś

Polymers 2021, 13(8), 1220; https://doi.org/10.3390/polym13081220 - 09 Apr 2021

Cited by 16 | Viewed by 2527

Abstract

The paper presents the results of research concerning the influence of micromaterials on the heat conductivity coefficient λ, specifically heat Cp and thermal diffusivity a of modified gypsum and geopolymer. Microspheres, hydroxyethyl methylcellulose (HEMC) polymer, and aerogel were used as the gypsum’s [...] Read more.

The paper presents the results of research concerning the influence of micromaterials on the heat conductivity coefficient λ, specifically heat Cp and thermal diffusivity a of modified gypsum and geopolymer. Microspheres, hydroxyethyl methylcellulose (HEMC) polymer, and aerogel were used as the gypsum’s modifying materials. The study also investigated an alkali potassium-activated methakaolin-based geopolymer with the addition of aluminium dust. During the measurements of thermal parameters, the nonstationary method was chosen, and an Isomet device—which recorded the required physical quantities—was used. When compared to the reference sample, a decrease in the thermal conductivity and diffusivity of the hardened gypsum— and a simultaneous increase in specific heat—was observed with the addition of micromaterials. The geopolymer sample was characterized by the lowest value of thermal conductivity, equal to 0.1141 W/(m·K). It was over 62% lower than the reference sample containing only gypsum. The experimental values of the thermal conductivity of the gypsum samples with the addition of HEMC, aerogel and microspheres were, respectively, over 23%, 6%, and 8% lower than those of the unmodified gypsum samples. The lowest values of thermal conductivity were observed in the case of the gypsum samples modified with polymer; this resulted from the fact that the polymer caused the greatest change in the structure of the gypsum’s composite, which were expressed by the lowest density and highest porosity. Full article

(This article belongs to the Special Issue Application of Polymeric Materials in the Building Industry)

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19 pages, 5137 KiB

Open AccessArticle

Restrained Stress Development in Hardening Mortar Internally Cured with Superabsorbent Polymers under Autogenous and Drying Conditions

by Jung Heum Yeon

Polymers 2021, 13(6), 979; https://doi.org/10.3390/polym13060979 - 23 Mar 2021

Cited by 5 | Viewed by 1866

Abstract

This study reports the results of a series of experiments, particularly paying attention to the early-age behavior and response of hardening mortars incorporating different types and contents of superabsorbent polymer (SAP) under autogenous (sealed) and drying shrinkage (unsealed) conditions. To achieve this primary [...] Read more.

This study reports the results of a series of experiments, particularly paying attention to the early-age behavior and response of hardening mortars incorporating different types and contents of superabsorbent polymer (SAP) under autogenous (sealed) and drying shrinkage (unsealed) conditions. To achieve this primary aim, the effects of SAP type (i.e., cross-linking density and grain size) and content on the internal relative humidity (IRH) changes and corresponding free shrinkage behavior, restrained stress development, and cracking potential of the mortar were extensively measured and analyzed, along with their strength and set time properties. The results of this study have shown that the internal curing (IC) via SAP effectively counteracted the early-age residual stress build-up due to autogenous shrinkage, as many other former studies described. No or little tensile residual stresses due to autogenous shrinkage took place when more than 0.4% SAP was added, regardless of the SAP type. However, it should be mentioned that the addition of SAP, irrespective of its content and type, hardly improved the shrinkage cracking resistance of the mortar when directly exposed to drying environment at early ages. Full article

(This article belongs to the Special Issue Application of Polymeric Materials in the Building Industry)

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13 pages, 5520 KiB

Open AccessArticle

Synergy Effect of Nano-Organic Palygorskite on the Properties of Star-Shaped SBS-Modified Asphalt

by Shuai Liu, Yuchao Gao, Jiao Jin, Huiwen Chen, Xinyu Liu, Ruohua Liu, Qingjun Guan, Yinrui Wu, Huaqiang Long and Guoping Qian

Polymers 2021, 13(6), 863; https://doi.org/10.3390/polym13060863 - 11 Mar 2021

Cited by 14 | Viewed by 1551

Abstract

With the rapid development of economic construction, styrene-butadiene-styrene (SBS)-modified asphalt is being more and more widely used in highway engineering, but there are still many deficiencies in the process of its use. In order to further improve its performance for use, nano-organic palygorskite [...] Read more.

With the rapid development of economic construction, styrene-butadiene-styrene (SBS)-modified asphalt is being more and more widely used in highway engineering, but there are still many deficiencies in the process of its use. In order to further improve its performance for use, nano-organic palygorskite (A-Pal) and star-shaped SBS were compounded to obtain modified asphalt in this study. The high-temperature stability of SBS-modified asphalt was enhanced after incorporation with A-Pal for the high-temperature stability test by a dynamic shear rheometer. The A-Pal should improve the surface free energy and adhesion of SBS-modified asphalt by the water stability test analysis. The aging test shows that A-Pal can reduce the thermal oxygen decomposition of SBS and improve the anti-aging performance and the fatigue resistance of SBS-modified asphalt. A-Pal has a certain improvement effect on the low temperature performance of SBS-modified asphalt as shown by a low temperature crack resistance test. A-Pal-compounded SBS-modified asphalt features good storage stability in normal temperatures with the lowest critical compatibility temperature. Full article

(This article belongs to the Special Issue Application of Polymeric Materials in the Building Industry)

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