Carbon Nanomaterials for Enhancing the Thermal, Physical and Rheological Properties of Asphalt Binders

Abstract

Effective thermal conduction modification in asphalt binders is beneficial to reducing pavement surface temperature and relieving the urban heat island (UHI) effect in the utilization of solar harvesting and snow melting pavements. This study investigated the performance of two nanometer-sized modifiers, graphene (Gr) and carbon nanotubes (CNTs), on enhancing the thermal, physical and rheological properties of asphalt binders. Measurements depending on a transient plant source method proved that both Gr and CNTs linearly increased the thermal conductivity and thermal diffusivity of asphalt binders, and while 5% Gr by volume of matrix asphalt contributed to 300% increments, 5% CNTs increased the two parameters of asphalt binders by nearly 72% at 20 °C. Meanwhile, a series of empirical and rheological properties experiments were conducted. The results demonstrated the temperature susceptibility reduction and high-temperature properties promotion of asphalt binders by adding Gr or CNTs. The variation trends in the anti-cracking properties of asphalt binders modified by Gr and CNTs with the modifier content differed at low temperatures, which may be due to the unique nature of Gr. In conclusion, Gr, whose optimal content is 3% by volume of matrix asphalt, provides superior application potential for solar harvesting and snow melting pavements in comparison to CNTs due to its comprehensive contributions to thermal properties, construction feasibility, high-temperature performance and low-temperature performance of asphalt binders.

Trends on Chlamydomonas reinhardtii growth regimes and bioproducts

“…Likewise, self‐flocculation is also a phenomenon studied in microalgae cultivation. In this case, the flocculating substances are produced by the microalgae themselves, which causes cell aggregation 55 . Though C. reinhardtii does not synthesize these molecules physiologically, they can be synthetized through genetic engineering 58 …”

“…Even though biomass harvesting was not an explored objective in these papers, this is the final, essential, and challenging step of microalgae cultivation, in industrial processes. 54,55 Besides the traditional methods, such as centrifugation or filtration, bio-flocculation is an example of a harvesting technique that is gaining more attention lately. This technique can be applied for other organisms, such as fungi, or substances extracted from them, such as chitosan.…”

Performance and Mechanism of High-Viscosity and High-Elasticity Bitumen (HVE-MB) Modified with Five Additives

“…In contrast, if the viscous part is dominant, δ tends to be larger and the bitumen is more likely to permanently deform and lose its ability to recover. The ratio of G* and δ (G*/sin δ) is used to evaluate the high-temperature properties of bitumen, while the product of G* and δ (G*•sin δ) is used to evaluate the fatigue resistance of the material [46].…”

Thermal Characteristics and Temperature Distribution of Asphalt Mixtures Containing Residues from Municipal Solid Waste Incineration

“…As a composite material, asphalt contains different heat transfer channels because of its components (i.e., coarse aggregates, fillers, and asphalt) [29]. Researchers have evaluated the effect of graphite on the thermal properties of asphalt mixtures [30]. They have found that asphalt-specific heat capacity decreases while thermal conductivity and diffusivity increase with the addition of graphite [31].…”