Mini-Review on the Application of Nanomaterials in Improving Anti-Aging Properties of Asphalt

Abstract

Exposed to detrimental environmental factors, such as heat, oxygen, and ultraviolet (UV) radiation, asphalt materials are prone to hardness and brittleness, namely, asphalt aging, which leads to deteriorating asphalt pavement properties and inducing a series of road distress. Theoretical and experimental studies have demonstrated that nanomaterial modifiers are a promising solution. This review discusses the application of single, compounded, and composited nanomaterial modifiers in improving the aging resistance of asphalt. Results showed that the introduction of single nanosilica, nanotitanium dioxide, and nanozinc oxide imparts positive effects on the anti-UV aging properties of asphalt, and single nanocalcium carbonate, carbon nanotubes, and layered silicates retard the thermo-oxidative aging rate of asphalt. Moreover, the multi-dimensional nanomaterial modifiers, a compound of nanometal oxide and layered silicates, comprehensively enhance the anti-thermo-oxidative and anti-UV aging properties of base asphalt and polymer-modified asphalt. Additionally, the composited nanomaterial modifiers could exert synergetic effects on asphalt properties and be a crucial area for future research. With the addition of nanomaterial modifiers, the asphalt aging processes are restrained by arresting volatile components of asphalt and lengthening the diffusion paths of oxygen molecules into asphalt binders. Another contribution mainly derives from functional groups against oxygen, which hinder the occurrences of oxidation reactions of asphalt. Many factors, such as nanomaterial modifier types, organic modification, nanomaterial concentration, and mixing methods and parameters, have influenced the anti-aging properties of nanomaterial-modified asphalt. In addition, the compatibility between nanomaterial modifiers with asphalt and nanomaterial dispersion in asphalt and the high costs involved in using nanomaterial modifiers are critical challenges for the application of nanomaterials in improving the aging resistance of asphalt. However, with cooperation between industrial communities and research institutes, an expanding application scale of nanomaterial-modified asphalt can be expected.

Comparative Investigation on the Properties and Molecular Mechanisms of Natural Phenolic Compounds and Rubber Polymers to Inhibit Oxidative Aging of Asphalt Binders

“…erefore, taking measures to actively inhibit the aging of asphalt is a better choice for building tough and durable road facilities. Current asphalt antiaging technologies, such as the incorporation of layered silicates and layered double hydroxides (LDHs) compounds, face the challenges of high cost and poor compatibility with asphalt, making them difficult to apply in engineering practice on a large scale [15,16]. In contrast, phenolic antioxidants from natural sources such as catechin, gallic acid, and lignin are widely available and have a similar molecular structure to asphalt, thus avoiding these disadvantages and becoming a promising raw material for the development of efficient asphalt antiaging technology [17].…”

A Novel Rejuvenating Method for Structural and Performance Recovery of Aged SBS-Modified Bitumen

“…The three-dimensional network structure formed by a styrene-butadiene-styrene triblock copolymer (SBS) in bitumen can render SBS-modified bitumen (SBSMB) extraordinary high- and low-temperature performance. , Nevertheless, when affected by aging factors like heat, oxygen, and ultraviolet radiation during the preparation and service period of bitumen materials, the butadiene block, an essential part of triblock structure of SBS, tends to be destroyed and oxidized, resulting in the fracture of copolymer chains. − In addition, the bitumen matrix also suffers irreversible constituent transformation from maltenes to asphaltene due to a series of reactions (volatilization, oxidation, condensation, polymerization, etc.) caused by thermal or photo-oxidation aging. − Both of the changes in polymer modifier and bitumen matrix can give rise to serious performance deterioration and service time decline of SBSMB pavement. , The renovation and reconstruction of the old or out-of-service pavement need to deplete unrenewable mineral and petroleum resources while creating a large amount of road waste materials.…”

Asphalt Binder “Skincare”? Aging Evaluation of an Asphalt Binder Modified by Nano-TiO2

“…With the volatilization of lightweight components during the aging process, the asphalt binder becomes harder and brittle rapidly [ 8 ]. The increasing brittleness of an asphalt binder can reduce its tensile strength and fatigue resistance, becoming prone to cracks under low-temperature or repeated loading conditions [ 9 , 10 , 11 ]. The aging process also reduces the adhesion performance of the asphalt mixtures [ 12 ].…”

“…Other studies also indicated that, when nano-ZnO particles are incorporated into asphalt binder, the viscosity aging index and the mass loss of the modified asphalt binder were inferior to those of the unmodified one after UV aging conditions [ 33 , 34 , 35 ]. Moreover, the introduction of nano-ZnO particles and expanded vermiculite in the asphalt binder improved its resistance to thermo-oxidative and UV aging at the same time, reducing the deterioration rates of the modified asphalt binder [ 11 , 26 , 32 , 36 ].…”

“…Nanomaterials have a great capacity to modify the microstructures of an asphalt binder, changing its performance [ 11 ]. Once nanomaterials have a high specific surface area, the use of high percentages can lead to increased stiffness, while low percentages do not.…”