Search Results (748)

Background: Polysaccharide–iron complexes (PICs) are widely used oral iron supplements, but their gastrointestinal tolerability varies and remains incompletely understood. As typical non-biological complex drugs (NBCDs), PICs exhibit structural heterogeneity, and their functional performance may be linked to higher-order structural attributes. Methods: In this study, two commercial PIC preparations (test samples A and B) were comparatively investigated to explore their structure–function relationship using a multi-dimensional approach. Structural properties were characterized by gel permeation chromatography (GPC), mass spectrometry (MS), Fourier-transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) spectroscopy, along with monosaccharide composition analysis. Functional behaviors and physiological relevance were further evaluated through in vitro acid-stress release studies and in vivo rat gastrointestinal tolerability assessments. Results: The results revealed that test sample A exhibited a glucose-only detectable monosaccharide profile but a higher and broader apparent molecular-weight distribution, indicating monosaccharide compositional uniformity together with macromolecular heterogeneity. In contrast, test sample B showed detectable glucose and mannose, a lower and narrower apparent molecular-weight distribution, higher measured free iron, and greater iron release under the tested acidic conditions. An exploratory 7-day rat gastrointestinal tolerability study (n = 4 per group) indicated that these distinct profiles may impact mucosal tolerability. Structurally stable test sample A allowed intestinal iron accumulation while maintaining mucosal integrity. Conversely, the rapid dissociation of test sample B induced observable mucosal injury, despite lower local iron retention. Conclusions: These findings suggest that the gastrointestinal tolerability of PICs may be associated with their structural attributes and release behavior, rather than total iron content alone. Overall, this exploratory study highlights a potential relationship between multi-dimensional PIC structure and functional performance, emphasizing the need for broader, structure-informed frameworks in the quality evaluation of complex iron therapies. Full article

Background/Objectives: Atopic dermatitis (AD) is a multifactorial inflammatory skin disorder in which epidermal barrier disruption and dysregulated immune responses drive persistent cutaneous inflammation. Owing to their broad spectrum of biological activities, marine-derived peptides have attracted increasing attention as potential therapeutic agents capable of modulating inflammatory and immune pathways. Methods: In this study, a novel peptide, WPN-15 (NGAIADQQPQRPNIV), was isolated from enzymatic hydrolysates of walleye pollock (Gadus chalcogrammus) tail by-products using an activity-guided purification process consisting of dialysis, fast protein liquid chromatography-gel permeation chromatography (FPLC-GPC), reverse-phase high-performance liquid chromatography (RP-HPLC), and electrospray ionization mass spectrometry (ESI-MS). The anti-inflammatory activity of WPN-15 was first examined in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages, and subsequently validated in a 2,4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis model using six-week-old male BALB/c mice. Results: WPN-15 significantly inhibited nitric oxide production in LPS-stimulated macrophages without causing cytotoxic effects. Topical administration of WPN-15 markedly alleviated DNCB-induced AD-like kin lesions, significantly reduced dermatitis severity scores, and decreased serum interleukin (IL)-6 levels. Histological evaluation further demonstrated that WPN-15 attenuated epidermal hyperplasia, dermal thickening, and mast cell infiltration. Furthermore, WPN-15 significantly downregulated the mRNA expression of IL-1β and IL-6 and inhibited signal transducer and activator of transcription 3 (STAT3) phosphorylation in skin tissues, indicating that its protective effects are mediated, at least in part, through the suppression of the IL-6/STAT3 signaling pathway. Conclusions: WPN-15 effectively attenuated inflammatory responses and pathological features associated with experimental AD. These findings demonstrate that walleye pollock tail by-products represent a valuable and sustainable source of bioactive peptides and support the potential application of WPN-15 as a marine-derived therapeutic candidate for the management of AD. Full article

In order to promote the sustainable development of road engineering, this study used waste tire rubber powder (RP) and surface organic layered double hydroxide (SOM-LDHs) to modify 70# matrix asphalt. The Box–Behnken design response surface method with three factors (rubber powder content, surface organic layered double hydroxide content, shear temperature) and three responses (penetration, ductility, softening point) was used to optimize the preparation parameters. The optimum formula was determined to be 21.7% rubber powder content, 4.8% surface organic layered double hydroxide content, and 160 °C shear temperature. The effect of the modifier on the surface morphology was analyzed using a rotating film oven test and ultraviolet aging test. The high and low temperature rheological properties of asphalt were evaluated by dynamic shear rheometer (DSR), bending beam rheometer (BBR), and the multi-stress creep recovery test (MSCR). The microstructure was observed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The aging mechanism was investigated by Fourier transform infrared spectroscopy (FTIR) and gel permeation chromatography (GPC). The results show that after aging, the complex shear modulus of rubber powder/surface organic layered double hydroxide composite modified asphalt is the highest, which is 27.35% higher than that of matrix asphalt. The rutting factor reaches 79.86 kPa at 46 °C, the phase angle decreases by 11.83% after UV aging, and the high temperature plastic deformation resistance is the best. In the low temperature range of −18 °C to −24 °C, the creep stiffness of the composite modified asphalt is about 30% lower than that of the matrix asphalt, while the m value is increased by about 15%, and the low temperature stress relaxation performance is significantly improved. The strain recovery rate of composite modified asphalt under 3.2 kPa stress reaches 78.5%, and the unrecoverable creep compliance is as low as 0.18 kPa⁻¹, which is better than that of matrix asphalt and single rubber powder modified asphalt. Full article

This study systematically evaluates the application prospects of three chemical recycling technologies for resource recovery from PET medical waste and the sustainable production of biomedical materials: catalytic pyrolysis, thermochemical recovery, and enzymatic hydrolysis. Orthogonal experimental designs and Box–Behnken response surface methodologies were used to optimise process parameters, and an extended assessment platform covering chemical purity, molecular weight distribution, biocompatibility, and mechanical properties was established. Under optimised conditions (200 $°$C, 3% w/w catalyst, 4 h, 6:1 ethylene-glycol-to-PET mass ratio), catalytic pyrolysis with zinc acetate achieved a terephthalic acid (TPA) recovery of 92.3 ± 1.8% at a product purity of 98.2 ± 0.5%, and retained 97.6% of the tensile strength and 97.4% of the elastic modulus of virgin PET. Although the enzymatic process was relatively long at 24 h, it had the best biocompatibility (L929 fibroblast viability 94.1 ± 2.2% and haemolysis 1.82 ± 0.28%) and reduced the carbon footprint by 46.5% compared to catalytic processing. Thermochemical recovery was completed in 1 h at 500 $°$C, achieving a TPA recovery of 71.2 ± 3.8%, and is suitable for large-scale processing of low-value medical waste streams. Biocompatibility tests showed that PET regenerated via the three paths met the ISO 10993 series of standards, with a cytotoxicity grade of 0–1 and an endotoxin content below 0.5 EU/mL. Gel permeation chromatography showed that the number-average molecular weight (M_n) of chemically recycled PET was between 21,200 and 24,100 g·mol⁻¹ (compared to 24,500 g·mol⁻¹ for virgin PET), approximately 86.5% to 98.4% of the virgin value, and significantly higher than mechanically recycled PET. The technical route and quality-control system established here provide a scientific basis for the closed-loop recycling of medical-grade PET and support the green transformation of the medical industry. Full article

The application of lignin as a sustainable replacement for phenol in resin is one of the main priorities in the polymer industry. The partial substitution of phenol by Kraft lignin in the synthesis of resole resin, a mineral and glass wool insulation binder, was thus investigated. Lignin was activated by phenolation in an alkaline medium at low temperature, followed by reaction with formaldehyde in the same batch. Conducting the phenolation reaction in an alkaline medium allows the synthesis of resol resin to continue without interrupting the process, while the low temperature ensures the low viscosity of the synthesized resol, which is a prerequisite for its use as a binder in the manufacture of thermal insulation products. This is an important innovation that streamlines the production of modified resol. Activated lignin and resole resins were characterized by Fourier transform infrared spectroscopy (FTIR) and gel permeation chromatography (GPC). Phenolation occurs mainly via the binding of phenol to the lignin macromolecule, increasing the molecular weight of activated lignin, with only small amounts of low molecular weight species observed. Resol resins with and without incorporated lignin have identical FTIR spectra and similar molecular weight distributions, which confirms the successful synthesis of lignin-containing resin. With essential relevance for the undisturbed production of thermal insulation products, the most suitable of the resins synthesized with lignin has appropriate viscosity, double the stability of the reference product, and half the amount of tetradimer (tetradimer can cause problems due to precipitation). In addition, this resin results in significantly lower emissions and has increased flexural strength. The synthesis is transferable to industrial practice. Full article

In this paper, a novel biobased phenol formaldehyde resin foam was fabricated. Specifically, lignosulfonate, a byproduct of paper and pulping, is hydroxymethylated with paraformaldehyde and then condensed with phenol to form lignosulfonate-based phenol formaldehyde (LPF) resin, subsequently undergoing foam technology to prepare LPF foam. The structures and properties of the intermediate and target products were characterized by ¹H nuclear magnetic resonance (¹H NMR) spectroscopy, gel permeation chromatography (GPC), Fourier transform infrared spectroscopy (FT-IR), thermogravimetry derivative thermogravimetry (TGA-DTG), scanning electron microscopy (SEM), compression performance test, limiting oxygen index test and thermal conductivity measurement. It was found that the prepared foam exhibited excellent mechanical and thermal properties. At a lignin substitution degree of 10%, the optimal thermal stability (at 800 °C), compressive strength (0.14 MPa) and thermal conductivity (0.0294 W/m·K) were achieved. As the lignosulfonate content gradually increases, the limit oxygen index initially showed a significant increase and then decreased. It is worth noting that when the LS substitution degree is increased to 30%, the limiting oxygen index of foam is up to 32.6%. These results underscore the application potential of industrial lignin as a promising biobased substitute in the synthesizing PF foam with excellent thermal insulation and flame-retardant properties. Full article

As the core binder material of asphalt pavement, the rheological properties of asphalt directly determine the service performance and service life of the pavement. Under actual service conditions, asphalt is constantly exposed to a multi-coupling environment involving temperature variation, vehicle load, and ultraviolet aging, which easily leads to irreversible rheological deterioration and induces diseases such as rutting and cracking. Aiming at the insufficient research on the rheological evolution law and microscopic damage mechanism under the coupling of the above three factors, this study took 70# base asphalt as the research object and adopted a combination of macro-performance testing and microstructure characterization. The high- and low-temperature rheological properties, permanent deformation resistance, and fatigue resistance of asphalt under multi-coupling effects were systematically evaluated through three conventional index tests: dynamic shear rheology (DSR), multiple stress creep recovery (MSCR), linear amplitude sweep (LAS) and bending beam rheology (BBR). Combined with gel permeation chromatography (GPC) and thin-layer chromatography with flame ionization detection (TLC–FID), the evolution laws of molecular distribution and chemical components were revealed, and the deterioration mechanism of multi-coupling effects was clarified. The results show that compared with the control group, after 72 h of coupling treatment, the penetration decreases by 32.6%, the softening point increases by 18.3%, and the ductility decreases by 45.8%. The high-temperature complex modulus decreases by 51.2%, the low-temperature creep stiffness increases by 76.4%, and the fatigue life decreases by 58.6% on average. At the microscopic level, obvious molecular polymerization and component weight gain occur in asphalt: the content of macromolecular components rises from 18.7% to 32.1%, asphaltene content increases from 12.3% to 25.8%, and aromatic content decreases from 42.6% to 28.3%. Temperature variation, load, and ultraviolet aging present significant deterioration effects, rather than a simple superposition of single factors. Prolonged aging and increased load aggravate the hardening of asphalt, while extreme temperature variation further weakens the rheological properties through microscopic damage. This study clarifies the internal relationship between the microscopic structure and macroscopic properties of asphalt under multi-coupling effects, improves the theory of anti-coupling damage to asphalt, and provides an important theoretical basis and experimental support for damage-resistant design, material selection, and service life prediction of asphalt pavement. Full article

To exploit medicinal and edible plant resources, this study investigated the extraction, structural characterization, and in vitro digestion of Elaeagnus angustifolia polysaccharide (EAP). Despite the nutritional value of this polysaccharide, its digestive properties remain unclear. Ultrasound-assisted extraction was optimized via response surface methodology. Crude EAP was purified by AB-8 macroporous resin purification and decolorization, followed by deproteinization and dialysis. The purified product (91.07% total sugar; 2.37% protein) was characterized by ultraviolet (UV) spectroscopy, Fourier-transform infrared (FT-IR) spectroscopy, high-performance liquid chromatography (HPLC), and gel permeation chromatography (GPC), and its digestion profile was assessed using a three-stage in vitro model (INFOGEST 2.0). Under optimal conditions, the crude polysaccharide yield (based on ethanol-precipitated solid; 87.83% total sugar) reached 2.44 ± 0.01%. EAP was identified as a pyranose-type polysaccharide, with glucose, mannose, and galactose as the predominant monosaccharides (relative molar proportions, 0.470:0.199:0.081, normalized to the total detected monosaccharides), with a weight-average molecular weight of 1.739 × 10⁵ g·mol⁻¹. In vitro digestion revealed negligible digestibility in the oral phase (0%), and low digestibility in the gastric (0.55%) and intestinal (2.76%) phases, with a cumulative digestibility of 3.30%. This marked resistance to gastrointestinal digestion indicates EAP is a partially digestible polysaccharide with potential prebiotic properties. The demonstrated resistance to gastrointestinal breakdown provides a theoretical basis for the high-value utilization of EAP in functional foods as a potential fermentable substrate for gut microbiota modulation. Full article

The effect of reversible addition–fragmentation chain transfer (RAFT) polymerization on the structure, morphology, and thermal degradation behavior of polypropylene glycol maleate–acrylic acid copolymers (p-PGM:AA) was investigated using 2-cyano-2-propyl dodecyl trithiocarbonate (CPDT) as the RAFT agent. Copolymers synthesized at different CPDT concentrations were characterized by ¹H/¹³C NMR spectroscopy, gel permeation chromatography (GPC), transmission electron microscopy (TEM), thermogravimetric analysis coupled with mass spectrometry (TG–MS), isoconversional kinetic methods, and density functional theory (DFT) calculations. ¹H NMR spectroscopy revealed a progressive decrease in the relative intensity of vinyl proton signals with increasing CPDT concentration, indicating enhanced conversion of unsaturated fragments during copolymerization. Alkaline hydrolysis followed by ¹H NMR and GPC analysis of the degradation products confirmed cleavage of polyester segments and yielded low-molecular-weight fragments with M_n = 1370 g mol⁻¹ and narrow dispersity (Đ = 1.035), providing additional information on the architecture of the vinyl-polymerized segments. Increasing CPDT concentration resulted in lower molecular weights and narrower molecular weight distributions of the soluble copolymer fractions. TEM analysis demonstrated broader domain size distributions and increased morphological heterogeneity in RAFT-modified samples, accompanied by an increase in swelling degree. Thermogravimetric analysis showed that RAFT-modified systems undergo multi-stage thermal degradation with the appearance of an additional low-temperature stage associated with thermolabile fragments. TG–MS revealed earlier evolution of CO₂ and oxygen-containing species and changes in the distribution of volatile products. DFT calculations indicated a decrease in the HOMO–LUMO energy gap and suggested the participation of RAFT-derived fragments in the energetic characteristics of decarboxylation processes. Isoconversional and nonlinear kinetic analyses demonstrated increased kinetic heterogeneity for branched copolymer s synthesized at elevated CPDT concentrations, whereas cross-linked systems exhibited more uniform degradation behavior. The combined experimental and theoretical results demonstrate that RAFT polymerization provides an effective route for tuning the macromolecular architecture, morphology, and thermal degradation pathways of p-PGM:AA copolymers. Full article

Size-exclusion chromatography (SEC) or gel-permeation chromatography (GPC) is an essential tool for determining the molecular weight and polydispersity of water-soluble polymers, including biopolymers used in hydrogels, sealants, bioinks, and other biomedical materials. However, aqueous SEC of polyelectrolytes, i.e., charged polymers, is often complicated by non-size interactions among polymer chains, porous column beads, pore surfaces, frits, tubing, and mobile phase. Salt addition to eluent is commonly used to screen these interactions, but the minimum salt concentration required to restore reliable SEC behavior remains poorly defined, and excessive salt may introduce tailing, refractive-index artifacts, deposits, or instrument concerns. In this study, aqueous SEC with refractive index (RI) and right-angle light scattering (RALS) detection was used to evaluate the effect of salt ($\mathrm{N}{\mathrm{a}}_2\mathrm{S}{\mathrm{O}}_4$) concentration on poly(ethylene oxide) (PEO), a nominally neutral reference standard polymer, and sodium alginate as a model anionic biopolymer. PEO retained a single bell-shaped peak across the tested salt range, but its elution volume and SEC/RALS-derived molecular weights varied slightly with salt concentration, showing that even a nominally neutral reference polymer is affected by mobile-phase conditions. Alginate showed much stronger salt dependence: eluent at very low salt concentration produced broad, noisy, and convoluted chromatograms, whereas increasing salt concentration progressively narrowed the main peak. The first condition that produced a clear, approximately symmetric RI/RALS main peak was $6.25\times {10}^{-3} \mathrm{M}$ $\mathrm{N}{\mathrm{a}}_2\mathrm{S}{\mathrm{O}}_4$, identifying it as the minimum effective salt concentration for this alginate/column/instrument system. To rigorously validate these observations, we propose a set of both qualitative and quantitative peak analyses that objectively confirm the optimal mobile-phase conditions. Ultimately, these results provide a practical workflow for identifying the minimum effective salt concentration required for reliable SEC analysis of water-soluble polymers. Full article

Mandelic acid, an aromatic α-hydroxy acid, has become a valuable scaffold in polymer chemistry, providing a rare combination of chemical reactivity and stereochemical control due to its aromatic ring, carboxylic acid group, and stereogenic center. In this work, racpoly(mandelic acid) (PMA) was synthesized via Dean–Stark Azeotropic Polycondensation, Steglich polyesterification with diisopropylcarbodiimide and 4-(dimethylamino)pyridinium p-toluenesulfonate, and a two-stage melt polycondensation. In the melt polycondensation synthesis titanium butoxide, titanium isopropoxide, p-toluenesulfonic acid, and sulfuric acid were investigated as appropriate catalysts. The synthesized samples were characterized using various techniques, such as intrinsic viscosity, Gel Permeation Chromatography, Differential Scanning Calorimetry, Dielectric Relaxation Spectroscopy, Thermogravimetric Analysis, Water Contact Angle measurements as well as enzymatic and aquatic hydrolysis tests. Although PMA has been synthesized before, this work provides the first comprehensive structure–property–degradation map for poly(mandelic acid) synthesized by melt and azeotropic polycondensation and Steglich polyesterification from the L,D-mandelic acid, combining detailed molecular weight analysis, thermal characterization, wettability, hydrolysis and dielectric probing of molecular dynamics. Full article

The scientific literature lacks sufficient data on the transport of various toxic pollutants by polymer particles. Investigating how the structure of microplastic particles formed during the degradation of polymeric materials affects pollutant sorption processes will improve our ability to predict environmental behavior. General-purpose polystyrene, expanded polystyrene, ABS plastic (acrylonitrile–butadiene–styrene) and crosslinked polystyrene are produced on an industrial scale. Copolymers of styrene with divinylbenzene are used on a large scale as sorbents for gel permeation chromatography (Styragel brand sorbents), in the production of catalysts on a polymer substrate or ion-exchange resins. In this study, non-spherical, crosslinked polystyrene microparticles with varying polystyrene chain packing densities were used as model microplastic particles representative of crosslinked polystyrene. It was shown that the adsorption of a hazardous chemical rhodamine B was influenced by both the packing density of the polystyrene chains and the presence of ionic functional groups, i.e., the “degree of aging” of the microplastic particles. The sorption capacities of these model microparticles were compared with those of natural origin (silicon dioxide, quartz powder, and microcrystalline cellulose). A viability assay using HEK293 and HeLa cell lines exposed to leachates from both pristine and rhodamine B-loaded microparticles revealed that all unmodified microparticles, regardless of their nature, exhibited no cytotoxicity at concentrations up to 1000 μg/mL. In contrast, microparticles with adsorbed rhodamine B significantly reduced cell viability to 20–40% at concentrations of 100 μg/mL. Full article

A novel water treatment agent, ethylenediamine–benzenesulfonic acid-modified polyaspartic acid (PASP-S), was controllably synthesized using an amino ring-opening reaction. The controllable synthesis methods, conditions for polymerization degree, and the molecular weight of the new polymer were explored. The structure was characterized using Fourier-transform infrared spectroscopy (FT-IR), ¹H nuclear magnetic resonance (¹H-NMR), and gel permeation chromatography (GPC). The scale inhibition, corrosion inhibition, and fluorescence properties of the new polymer, as well as the corresponding mechanisms, were investigated using static scale inhibition tests, electrochemical measurements, X-ray photoelectron spectroscopy (XPS), density functional theory (DFT), and frontier molecular orbital (FMO) theory. The results indicate that PASP-S exhibits strong Ca²⁺ chelation ability and can effectively inhibit CaCO₃ and CaSO₄ scaling. At 50 mg/L, the scale inhibition efficiency for Ca₃(PO₄)₂ reaches 99.50%. At 30 mg/L, its corrosion inhibition efficiency is 33.19% higher than that of PASP. Unexpectedly, the polymer shows remarkable selective antibacterial activity. At 100 mg/mL, the inhibition rate against Escherichia coli (E. coli) is 71%, while no obvious inhibition is observed for Bacillus cereus. A good linear relationship is found between fluorescence intensity and concentration. Mechanistic studies demonstrate that PASP-S adsorbs on the scale surface, suppressing crystal growth and distorting crystal morphology. Meanwhile, it forms a protective film on the electrode surface, thus reducing the dissolution and corrosion of carbon steel. Full article

The utilization of waste, defined as commercially worthless or discarded material, is becoming an increasingly important topic in the context of environmental material overload. Thus, the development of new products should integrate waste, adding commercial value to materials that would have otherwise been discarded. In this context, Material Extrusion (ME), the most widely used technique in Additive Manufacturing (AM), has introduced a new manufacturing model, opening opportunities for developing innovative products. On the other hand, during the beneficiation process of ornamental rocks, tons of mineral waste are generated. This study aims to develop a polylactic acid (PLA) filament using Beige Bahia marble waste as a raw material source via the ME technique. Compositional mapping through Energy Dispersive Spectroscopy (EDS) indicated that, as the mass fraction increased, particle clustering within the PLA matrix decreased. Mass compositions ranging from 0–30% mineral waste to PLA were evaluated. Gel Permeation Chromatography (GPC) showed that the PLA molar mass in the PLA00 and PLA30 compositions was 109,103 and 120,103 g.mol⁻¹, respectively, indicating that the mineral waste helped preserve the polymer’s molar mass during material processing. An increase was observed in the elastic modulus. The total roughness profile demonstrated higher values for pure PLA, while the partial roughness profile showed higher noise due to the greater presence of particles on the surface. The final product exhibited characteristics like the original rock and could serve as an alternative when such features are desired. Full article

Owing to the pronounced compositional heterogeneity of waste cooking oil (WCO), WCO-rejuvenated asphalt often exhibits unstable performance. To improve the compositional controllability of WCO-based rejuvenators, WCO was fractionated according to molecular weight differences into three characteristic fractions: light, medium, and heavy components. Nine rejuvenator formulations with different component ratios were prepared to investigate the synergistic mechanism among WCO fractions with different molecular weights and to propose an optimal blending range. Thermal stability tests, dynamic shear rheometer (DSR) tests, multiple stress creep recovery (MSCR) tests, and bending beam rheometer (BBR) tests were conducted to evaluate the performance of the rejuvenators and rejuvenated asphalts. Gas chromatography (GC) and gel permeation chromatography (GPC) were further used to analyze the chemical composition and molecular-weight distribution. The results show that increasing the proportions of light and medium WCO components improves the low-temperature performance of rejuvenated asphalt; however, when the combined content of light and medium components exceeds 40%, the high-temperature performance is adversely affected. The heavy component improves the rutting factor, creep recovery capacity, and thermal oxidative aging resistance of rejuvenated asphalt, and the coefficient of determination between the long-term aging CAI and heavy-component content reaches 0.959. Thermal stability tests show that the mass loss rate of the nine rejuvenators after 1.5 h of heating ranges from 2.8% to 4.3%, with greater mass loss for formulations containing higher light-component contents. GPC results show that the Mn and Mw of R-4 (492 g/mol and 641 g/mol) are higher than those of R-8 (463 g/mol and 600 g/mol), indicating that a higher macromolecular fraction contributes to improved thermal stability. Considering high-temperature, low-temperature, and aging performance together, rejuvenated asphalt achieves the closest overall performance to the base binder when the heavy component is controlled at 50–60% and the medium component is approximately 30%. Full article