Properties Of Binders Research Articles

Evolution of Rheological and Microscopic Properties of Asphalt Binders under Fuel Corrosion

Vehicle fuel leaks can adversely affect the performance of asphalt pavements. To study the mechanisms of fuel corrosion damage in asphalt, four asphalt binders were selected in this study, and the evolution of their rheological and microscopic properties was investigated. Fuel corrosion caused continuous mass loss in asphalt binders. Base asphalt lost more than 50% of its mass after 24 h of fuel corrosion, while modified asphalts had better resistance. According to dynamic shear rheometer tests and multiple stress creep recovery tests, modifiers improved the high-temperature rheological properties of these asphalt binders. As the degree of fuel corrosion deepened, the indexes characterizing the high-temperature performance deteriorated. Rubber-modified asphalt showed the best resistance to high-temperature deformation, while the performance of LDPE-modified asphalt was more stable. In contrast, fuel corrosion improved the resistance of asphalt binders to low-temperature cracking to some extent: the creep strength (S) decreased as the creep rate (m) increased, and the resistance of SBS-modified asphalt to low-temperature cracking was optimal, with a 36% decrease in S-value after 24 h of fuel corrosion. Fourier transform infrared spectroscopy tests showed that diesel corrosion was a process of this physical dissolution, with no change in the chemical functional groups. Meanwhile, by using fluorescence images and analyzing the four-component test results, we found that fuel corrosion disrupted the stabilized structure formed by the modifiers, and the heavy components in the asphalt binders were converted into light components. This study reveals the evolution of the rheological and microscopic properties of asphalt under fuel corrosion, which can provide a reference for the optimization of fuel corrosion resistance in asphalt pavement.

Effect of SBS/SBR/component molecular compatibility on anti-aging properties for asphalt binder

To explain the effect of SBS/SBR/component molecular compatibility on anti-aging properties for asphalt binder, the micro-aging behavior of SBS/SBR composite modified asphalt binder was studied by molecular simulation, scanning electron microscopy (SEM) and infrared spectroscopy (IR). First, the micro-models of SBS molecule, SBR molecule and component molecule (asphaltene, resin, saturation, aromatic) were established, and the molecule number was determined by component test. Additionally, the characteristics of micro-model were analyzed, and the change characteristics of molecular compatibility for unaged asphalt binder and aged asphalt binder were obtained. Lastly, the rationality of molecular compatibility simulation results of SBS/SBR/component was demonstrated by SEM and IR tests, respectively. The results show that there is a close relationship between SBS/SBR/component molecular compatibility and asphalt binder anti-aging performance. The change of molecular space structure leads to the increase of asphalt binders density and the decrease of intermolecular distance. The study revealed the anti-aging properties of asphalt binder from the aspect of SBS/SBR/component molecular compatibility, which provided a theoretical foundation for the improvement of its aging resistance.

Evaluation of Rheological Properties of Polymer-Modified Asphalt Binders and Mastics with Organic Additive—Imidazoline

The article presents the results of testing the asphalt binder modified with SBS copolymer (5%) and its mixture with mineral fillers called asphalt mastics. The aim of the research and analysis was to check the possibility of using an organic additive in the form of imidazolines and to assess their impact on the viscoelastic properties of the obtained asphalt mastics. The main advantage of using imidazoline is the increased resistance of asphalt mixtures to low-temperature cracking at the top of the road route and reducing its maintenance costs. Based on the examination of the adhesion of the binder with the addition of various imidazolines to the aggregate, a selection was made from six analyzed subtypes. One of them was selected for further research. The tests were carried out in a dynamic shear rheometer in a wide temperature range from −36 °C to 82 °C, determining the most important parameters of the tested materials, i.e., dynamic shear modulus (|G*|), phase angle (δ) and the non-recoverable creep compliance (Jnr). The test results and their analysis confirmed the beneficial effect of imidazoline on the viscoelastic properties of mastics in the low-temperature range, even at the lowest content of 0.2%. Based on the results of the determination of Jnr and |G*|/sinδ in the range of high operating temperatures, no significant deterioration in permanent deformation parameters was observed. Moreover, the use of imidazoline reduces technological temperatures during the production of HMA used in the pavement and, therefore, reduces CO2 emissions into the atmosphere.

Effect of High-Density Polyethylene Pyro-Oil Modification on Chemical, Rheological, and Damping Properties of Binders

Effect of High-Density Polyethylene Pyro-Oil Modification on Chemical, Rheological, and Damping Properties of Binders

Development of a Framework for Assessing Bitumen Fatigue Cracking Performance under Different Temperatures and Aging Conditions

A full understanding of bitumen fatigue cracking behavior is extremely important as this phenomenon has a considerable influence on bituminous pavement performance. The current framework for assessing this asphalt binder property is inconsistent in ranking bitumen fatigue performance in terms of the failure definition and damage characteristic curve (DCC) analysis. This study used four different types of asphalt binders: neat asphalt (NA), self-healing thermoplastic polyurethane (STP)-modified bitumen, self-healing poly (dimethyl siloxane) crosslinked with urea bond (IPA1w)-modified bitumen, and styrene–butadiene–styrene (SBS)-modified bitumen (SBSB). All the bitumens were subjected to short-term and long-term aging, and they were also tested by utilizing the linear amplitude sweep (LAS) test and the simplified viscoelastic continuum damage (S-VECD) model. LAS and S-VECD procedures were used to apply the newly proposed and current frameworks in order to analyze bitumen performance. The current framework showed that the bitumens that used a higher number of loading cycles (N) to reach their failure points (Nf) failed to exhibit greater fatigue performances in terms of DCC analysis. The developed framework (mainly based on the damage intensity [S] instead of N) was used to solve the inconsistency between the failure definition and DCC assessment in ranking bitumen performance. Additionally, the current framework (failure criterion) presented two R2 values below 0.1, but the developed framework (failure criterion) showed that all R2 values were greater than 0.9. The developed framework represents a turning point because, for the first time, this type of procedure is mainly being based on S instead of N. Although further tests are needed to confirm its efficiency, it eliminates the inconsistency between the failure definition and DCC assessment.

Thermoreversible aging in asphalt binders

It is an undisputed fact that aging increases the risk of low-temperature cracking in asphalt pavement. Previous studies on aging have focused on oxidative aging, but few studies on thermoreversible aging have been reported. The existing literature has shown that thermoreversible aging has the same effect as oxidative aging on cracking of asphalt pavement in cold region, so it is obvious that the study of thermoreversible aging is of great practical significance to improve cracking of asphalt pavement. This paper introduces the current status of thermoreversible aging research from the concept, mechanisms, characterisation methods and effects, presents the problems of existing research and indicates the direction of further research, which is important for accurately characterising the mechanical properties of asphalt binders, controlling the waste addition ratio and improving the durability of asphalt pavement.

The role of adding nanoparticles and surfactant to the enzyme liquid binder in fluidized bed granulation process

The influence of enzyme liquid binder properties on wet granulation process was evaluated at both micro- and macro-scales. The micro-scale phenomena, including binder droplet spreading on and penetration into the powder bed, as well as liquid bridge shape and force, were analyzed by introducing SiO2 nanoparticles and SDS surfactant into the liquid binder containing a protease enzyme and 1 wt% of NaCMC. Moreover, the simultaneous effect of formulation variables, including NPs and SDS concentrations, and process conditions, such as binder spray rate and air temperature, was investigated using design of experiments. The average size and the span were considered as the responses. Nanofluid binder without SDS exhibited lower spreading and penetration times and a stronger bridge force. All formulation and process factors significantly influenced granule size distribution. Notably, increasing nanoparticle concentration and binder flow rate, while decreasing SDS concentration and air temperature, resulted in larger granules and a narrower size distribution.

Low-temperature aliphatic eutectic phase change materials for asphalt: Design and characterization

Cost and thermal stability are critical for the application of low-temperature phase change materials (PCMs) in asphalt pavements. Aliphatic eutectic phase change materials (AEPCMs) are expected to be potential candidates for new low-temperature PCMs. The objective of this study was to develop a set of low-temperature AEPCMs with a phase transition temperature of − 3.58 to 16.21 °C and a latent heat of 144.01 to 195.96 J/g in an attempt to replace tetradecane (TD). To fully evaluate the properties of low-temperature AEPCMs and TD, and the impacts of their direct incorporation into asphalt, the chemical structures, enthalpies, mass retention, economic costs, and changes in the physical and rheological properties of the modified asphalt were investigated. The results showed that AEPCMs with a phase transition temperature similar to that of TD could be obtained by eutectic crystallization and retained the chemical properties of their components. However, the latent heat decreased progressively with the increase in the number of components. The AEPCMs exhibited higher thermal stability than TD, with a maximal increase in mass retention from 37.24% to 86.66% at 180 °C. In addition, AEPCMs exhibited significant cost advantages. The most inexpensive AEPCMs synthesized in the laboratory is only 112.01 ¥/kg and an enthalpy cost of 0.57 ¥/kJ, accounting for 30.1% and 35.8% of TD cost, respectively. Incorporation of AEPCMs and TD increased the lightweight component of asphalt binders and caused damage to the conventional physical and rheological properties of asphalt binders, but polar AEPCMs had fewer deleterious effects on asphalt compared to nonpolar TD.

Evaluation of chemical composition and physical properties of bituminous binders and fractions

Bituminous binders are foreseen as colloidal dispersed systems characterised by high chemical complexity containing a plethora of molecules classified into maltenes and asphaltenes. The effect of these fractions on the overall response of bituminous binders remains elusive. This research selected two binders from the same refinery but with different paving grades. First, Dynamic Shear and Bending Beam Rheometers were employed to assess their rheological properties, and results were consistent with the physical measurements conducted on binders to address low to high temperature rheological response. Then, the binders and their fractions were individually analysed in a Fourier transform infrared spectroscopy and differential scanning calorimetry to elucidate their chemistry associated with the structural changes. No significant difference could be noticed in the infrared spectra of binders, even if they displayed diverse physical properties. Differences may be identified in asphaltenes, an observation which is also supported by calorimetric measurements where steric hindrance occurred upon heating. Maltenes contributed significantly to the glass transition of both binders, while the impact of asphaltenes on the heat capacity changes in glass transition was limited. The findings from this research could be used to establish a new analytical approach for bituminous binders to understand the differences in the physical properties of binders based on their chemistry.

State of the Art Review of Ageing of Bituminous Binders and Asphalt Mixtures: Ageing Simulation Techniques, Ageing Inhibitors and the Relationship between Simulated Ageing and Field Ageing

Asphalt mixtures age during service in the field, primarily as the result of chemical changes in the bituminous binder phase. The ageing phenomenon changes the properties of the asphalt mixture, including the stiffness modulus, the resistance to deformation and the resistance to cracking, and it leads to surface weathering or erosion that often leads to pavement resurfacing. Consequently, many researchers have attempted to understand and to simulate the ageing of bituminous binders and asphalt mixtures in the laboratory. This review of bituminous binder and asphalt mixture ageing considers ageing simulation techniques, the effect of ageing on both bituminous binders and asphalt mixtures, the potential benefits of ageing inhibitors, and efforts to relate simulated laboratory ageing to observed field ageing. It is concluded that ageing has a significant effect on the properties of bituminous binders and asphalt mixtures, and that improved simulated ageing is important for comparing the effect of ageing on different materials and mixtures, as well as for quantifying the potential benefits of ageing inhibitors, which have generally been promising. It is also concluded that current ageing protocols are based on heat only, omitting the important contribution of solar radiation to the weathering and ageing of asphalt surfaces in the field. In the future, different simulated ageing protocols should be developed for binder and mixture samples. Similarly, a different ageing protocol is appropriate for understanding base-layer fatigue, compared to research on surface-layer weathering. Finally, it is concluded that a universal ageing protocol is unlikely to be found and that mixture- and climate-specific protocols need to be developed. However, given the importance of simulated ageing to asphalt researchers, the development of reliable, robust and calibrated laboratory ageing protocols is essential for the future.

Green synthesis of polyurethane with reversible oxime-urethane bond to enhance the self-healing properties of asphalt binder at room temperature

The oxime-urethane group can undergo dynamic reversible reaction at room temperature, which can endow polyurethane (PU) with self-healing ability at ambient temperatures. This study prepared CO2-based PU containing oxime-urethane groups and introduced it into asphalt to enhance the self-healing performance of asphalt at room temperature. Firstly, the chemical structure, self-healing performance, and thermal stability of the prepared PU and ordinary PU were characterized. Then, the two types of PU were sheared in asphalt to prepare PU modified asphalts, the chemical characteristics and microstructure of the modified asphalts were characterized. Finally, the healing performance of different asphalts at room temperature was characterized. The results indicated that the prepared self-healing PU had good thermal stability and exhibited rapid self-healing performance at room temperature. After 6h of healing, the maximum tensile strength can recover to 88.78% of its initial value. Self-healing (S-PU) was successfully introduced into asphalt system without decomposition, but due to the role of intermolecular hydrogen bond and dynamic covalent bond of PU, its dispersion in asphalt was poor. The addition of S-PU can significantly enhance the self-healing capability of asphalt at room temperature. This study provides a new idea for the preparation of green PU modified asphalt containing dynamic covalent bond.

Study of thermal state, water absorption and strength properties of composite polymerpolymer binders

In this article, in order to improve the heat-water resistance and strength properties, the modification of urea-formal- dehyde polymeric materials is considered by introducing melamine and acrylonitic resins and reactive compounds into their composition. Shown by identifying the optimal ratios of urea-formaldehyde, melamine and acrylonitrile resins and the corresponding reactive compounds in increasing the heat-water resistance and shear strength of adhesive joints based on them, replacing expensive phenol-formaldehyde resins used in gluing basalt fibrous masses in the production of build- ing heat-insulating sheet materials.

АНАЛІЗ ВПЛИВУ ПОЛІФУНКЦІОНАЛЬНОГО МОДИФІКАТОРА НА ВОДОСТІЙКІСТЬ КОМПОЗИЦІЙНОГО ГІПСОВОГО В'ЯЖУЧОГО

The article highlights the issue of increasing the water resistance of a composite gypsum binder based on the analysis of a full-scale experiment. To solve the problem, a 24-point plan in the form of "triangles on a cube" of the experimental and statistical model of the effect of additives of various types and purposes on the properties of a composite gypsum binder, taking into account the interactions between them, calculated in the COMPEX program, was used. A universal method of increasing the water resistance of gypsum materials is to reduce their porosity. For this purpose, small amounts of polymeric or plasticizing additives are introduced into the gypsum binder to increase their density. A way to increase water resistance is to add up to 10-40% of mineral components, which, due to their binding properties, harden into a water-resistant stone-like material. At the first stage of the experiment, we analyzed the change in water resistance by the value of the softening coefficient Kr under the influence of micro-puzzolan additives, a micro-reinforcing modifier additive, and Sika superplasticizer. The range of variation of all additives was established by the experiment plan. The next stage of the study analyzed the possibility of further improving water resistance by using bulk and surface water repellents. To evaluate the effect of hydrophobic primers on the surface properties of gypsum binder samples, the marginal wetting angle is measured using the sitting drop method. It is shown that the complex modification of the composite gypsum binder with micro-reinforcing, polymineral micro-puzzolanic filler additives and Sika superplasticizer in optimal proportions makes it possible to obtain a composite gypsum binder with a softening coefficient of 0.9. Volumetric hydrophobization provides an additional increase in compressive strength and water resistance.

Palm Oil Fuel Ash, Garnet Waste and Sawdust as Modified Asphalt Mixture: A Critical Review

The addition of palm oil fuel ash (POFA), garnet waste, and sawdust as a modified asphalt binder and mixture for paving materials show that recycling materials from industrial and agricultural waste have been implemented with environmental concern, increasing the proper handling of this waste product. The use of POFA, garnet waste, and sawdust as a modifier to improve the properties of binder and mixture is critically evaluated in this study. The review focuses on the evaluation of POFA, garnet waste, and sawdust in asphalt binder and mixture modification. In essence, the combination of POFA, garnet waste, and sawdust offer a promising waste materials potential to enhance the rheological and mechanical performance of the modified binder and mixture. The use of this modification in the binder and mixture is expected to improve performance and be on par with the traditional asphalt binder and mixture.

Research progress of robust binders with superior mechanical properties for high-performance silicon-based lithium-ion batteries

The mechanical properties of binders are emphasized: the intrinsic mechanical properties of binders and the adhesive strength of the binders with current collectors and active materials. The electronic and ionic conductivities of binders are introduced.

Mechanical and rheological properties of polyurethane-polyurea (PU-PUa) modified asphalt binder

Polyurethane (PU) is one of the common polymer modifiers used for asphalt, and the PU modified asphalt currently plays a fundamental role in road constructions. However, most of the PU as the modification could bring about an increasement in viscosity and rigidity to asphalt binders, thus leading to insufficient ductility and deformation compatibility for the materials to some extent. In the present study, a composite polymer material synthesized with polyurethane and polyurea (PU-PUa) was introduced as a modifier to the asphalt binder in an attempt to integrate their individual advantages into the asphaltic material. The curing time, tensile strength, and Fourier Transform infrared spectroscopy (FTIR) tests were conducted to determine the optimal proportion of the PU and PUa in the compound polymer, and its formation mechanism was also discussed. The fundamental properties of the asphalt binders modified with various contents of PU-PUa (5%, 10%, and 15% by weight), such as the storage stability, rheological properties, creep recovery capacity, and fatigue resistance, were investigated through the thermal storage, dynamic rheological, stress creep recovery (MSCR), and linear amplitude sweep (LAS) tests. Furthermore, in order to understand the adhesion property of the PU-PUa modified asphalt on aggregates, the pull-off tests considering both dry and water immersion conditions were performed. The test results showed that the PU-PUa could be effectively used to modify asphalt binders, and 7:3 was found to be the best proportion of the PU and PUa. The addition of PU-PUa could promote the high temperature performance, enhance the recovery ability for creep, and extend the fatigue life of the asphalt binders (for both 70# and SBS asphalt). The optimal content of PU-PUa for the modification was found to be 10% based on the storage stability and mechanical performance of the modified asphalt binders.

Comparison of elvaloy and styrene-butadiene-styrene added polymer modified bitumen

One of the methods used to produce road pavements resistant to increased traffic volume and harsh environmental conditions is to improve the properties of bituminous binders, such as high temperature resistance and aging resistance, by using various additives. Styrene-Butadiene-Styrene and Elvaloy are two different commercial additives that are frequently used in pavement construction. In this study, the performance of three different B50/70 grade pure bitumens was modified by using Elvaloy at 1.6%, 1.7%, and 1.8%, and five different B50/70 grade pure bitumens were modified using 4.0%, 4.5%, and 5.0% Styrene-Butadiene-Styrene. Penetration, softening point, elastic recovery, flash point, storage stability, dynamic shear rheometer, beam bending rheometer, rotational thin film oven, and pressure aging vessel tests were applied to the binders in accordance with the Polymer Modified Bitumen technical specifications. According to the test results, it was determined that the additive rates for both modifiers are the optimum values in accordance with the specification. The results of the storage stability tests also showed that the non-homogeneous dispersion of the Styrene-Butadiene-Styrene modified binders during mixing had a significant effect on the behaviour of the binder after storage.

Effect of aging on damping properties of rubberized asphalt binder and rubberized porous asphalt mixture

The purpose of the study is to explore the effect of aging on the damping properties of rubberized asphalt binder and rubberized porous asphalt mixture (RPAM), and to reveal the attenuation mechanism of damping properties. The effect of aging on the damping properties of asphalt binder was analyzed through temperature scanning test. Fourier transform infrared spectroscopy, gel permeation chromatography, and fluorescence microscopic test were conducted to analyze the aging mechanism of damping properties from the perspectives of chemical composition and morphology. The dynamic modulus test and free vibration damping test were used to investigate the effect of aging on the damping properties of asphalt mixtures. Results showed that aging led to a decrease in the damping properties of asphalt mixtures. Compared to porous asphalt mixture, RPAM had lower sensitivity to aging, so its damping properties was less prone to decay. The effect of aging on asphalt binders obtained from the temperature scanning test was consistent with the results of asphalt mixtures, indicating that the decrease in damping properties of asphalt mixtures was attributed to the deterioration of damping properties of asphalt binders. The results of chemical composition and phase morphology indicated that the proportion of large molecules in the asphalt binder increased significantly during the aging process. The decrease in intermolecular mobility led to a decrease in the damping properties of asphalt binder. Significantly, crumb rubber can prevent the aging of asphalt binder, thereby delaying the attenuation of damping properties of RPAM.

Effects of crumb rubber and styrene-butadiene rubber additives on the properties of asphalt binder and the Marshall performance properties of asphalt mixtures

The primary aim of this study is to evaluate the impact of incorporating crumb rubber (CR) and styrene-butadiene rubber (SBR) additives, ranging from 0% to 5% by weight of bitumen, on the performance of a bituminous concrete mixture using the wet process. Laboratory experiments, including the Marshall test, were conducted to establish the optimum bitumen content (OBC) for the hot mix. The study focuses on determining the optimal proportions of CR and SBR to achieve maximum strength. The results show that increasing the proportions of both CR and SBR leads to significant improvements in strength, with the maximum stability recorded at 16.14 kN and a flow of 1.23 mm for a mix containing 5% CR and 4% SBR. The findings further suggest an inverse relationship between CR content and strength, while an increasing SBR content enhances strength. Consequently, the optimal proportions for incorporating CR and SBR additives are identified as 5% and 4%, respectively.

Study of the Viscoelastic and Rheological Properties of Rubber-Bitumen Binders Obtained from Rubber Waste.

According to scientific research from different countries, crumb rubber obtained from end-of-life tires (ELT) during processing can improve the properties of the asphalt mixture, thereby extending the service life of the road surface. This paper presents the modification of bitumen with industrial rubber waste. The modification of bitumen for roads is considered one of the most suitable and popular approaches. This research paper describes the details of using different types of crumb rubber as bitumen modifiers. The modified bitumen's main physical and mechanical characteristics were determined after conventional tests: penetration and ductility, softening point, and Fraas brittleness point. In order to obtain a rubber-asphalt concrete mixture with improved performance characteristics, the viscoelastic and rheological properties of rubber-bitumen binders and their comparison with polymer-bitumen binders were also studied. The research results show that with increasing temperature, the values of viscosity, shear stress and complex shear modulus of all studied bitumen systems decrease, the values of the phase shift angle increase, and the size of the rubber particles has a greater influence on the properties of bitumen systems.