High Temperature Viscosity Research Articles

4D Printing of Ultra‐High Performance Shape Memory Polymer for Space Applications

Developing thermoplastic polyimide (TPI), capable of handling space conditions, through 4D printing is challenging due to its high melting temperature and inherent viscosity. This study presents 4D printing of TPI for shape memory investigation under repetitive cycles for the first time, exploring its potential for self‐deployable hinges in space devices. 4D‐printed TPI exhibits outstanding shape memory effect (SME) with shape fixity (Rf) up to 100% and shape recovery (Rr) of 100% in first cycle. Rf is noted to be increasing up to third cycle and then fixed to 100% up to tenth cycle, while Rr shows a decreasing trend in subsequent cycle with a drop of 37% in tenth cycle. Moreover, it exhibits extremely high glass‐transition temperature, Tg = 263.10 °C, degradation temperature, Td = 520 °C, and storage modulus of 1600 MPa. Among existing high‐performance (HP) and conventional shape memory polymers (SMPs), 3D‐printed TPI exhibits superior performance. Tg of the TPI is found to be 66.52%, 107.16%, and 62.41%, higher than existing HP‐SMPs, polyether ether ketone (Tg = 158 °C), polyamide (Tg = 127 °C), and polyether ketone ketone (Tg = 162 °C), respectively. This investigation reveals a novel characteristic, the SME, of 4D‐printed TPI with ultra‐high Tg and Td, demonstrating suitability for self‐deployable hinges, contributing to materials engineering and 4D printing.

Study on the Effect of Nitrogen Bubble Foam Flooding in Deep Heavy Oil Reservoirs with Edge And Bottom Water

Abstract The oil recovery rate is low, the degree of recovery is low and the water content rises fast after water flooding in deep edge and bottom water heavy oil reservoir in Lukeqin oilfield. In order to explore the method to improve the production effect, the integrated foam system of high temperature and high pressure resistant viscosity reduction and oil displacement is optimized. On the basis of clarifying the mechanism of improving the production effect of nitrogen foam flooding for deep heavy oil, taking the west area of Lukeqin oilfield as the research object, the parameter optimization design of nitrogen foam flooding for deep edge and bottom water heavy oil is carried out, such as injection section plug, gas-liquid ratio and injection-recovery ratio. The optimization results are as follows: the injected nitrogen foam slug is 0.2pv, the gas-liquid ratio is 1-1.2, and the injection production ratio is 1:1. The pilot test of 4 well groups was carried out on the site. After foam flooding, the injection pressure was increased by 5.2mpa, the daily oil production of the oil well was increased by 43T / D, the water cut was decreased by 45%, the accumulated oil production was increased by 32000 tons, and the oil recovery was expected to be increased by more than 10%. The purpose of improving the development efficiency of this type of oil reservoir was achieved. Using this optimization technology for scheme design and field implementation, the oil enhancement effect is remarkable and improves the benefit of deep thick oil development, which can provide technical support for the development of similar domestic reservoirs.

Recycling of arsenic residue to basalt fiber via vitrification

The management of arsenic residue (AR) poses a significant environmental challenge globally. Conventional methods such as landfill, adsorption, and purification often fail to prevent arsenic migration, leading to uncertainties about the final disposition of AR and risks of secondary pollution. Vitrification offers a more stable approach for solidifying AR. This study explores the vitrification mechanism of AR using basalt and evaluates the performance of the resulting fibers. Our findings indicate that increasing the arsenic concentration decreases the high-temperature viscosity of basalt, making fiber drawing more energy-efficient. Incorporating a small amount of arsenic (approximately 0.4 mol%) significantly enhances the tensile strength of basalt fibers (BFs) by 10 %, attributed to reduced viscosity and improved fiber formation with fewer internal defects. Additionally, the flexural strength and stiffness modulus of asphalt mixtures are notably improved with the addition of AR-BF composites. We also examined the solidification and leaching mechanisms of arsenic in the basalt glass system. BFs containing up to 0.4 mol% As2O3 exhibited arsenic leaching levels below the standard threshold (<67.7 μg/dm2) under strong acid/alkali immersion conditions. These results highlight the potential for in-situ curing and recycling of hazardous AR, particularly in the development of mechanically reinforced materials.

Underfill epoxy has high glass-transition temperature and low viscosity

Underfill epoxy has high glass-transition temperature and low viscosity

Effect of Ce2O3 content on structure, viscosity, and melting properties of CaO-Al2O3-MgO-SiO2-Ce2O3 slag

To ensure the reliable operation of high aluminum steel smelting, it is common practice to employ low-reactivity CaO-Al2O3-based slag. Various analytical methods, including scanning electron microscopy with energy-dispersive X-ray spectroscopy, X-ray diffraction, Raman spectroscopy, and so on, are employed to investigate the impact of Ce2O3 content on the crystalline phase and structure within the CaO-Al2O3-MgO-SiO2 slag. Concurrently, the slag properties of viscosity and melting temperature are assessed. The findings reveal that the principal crystalline phases in the CaO-Al2O3-MgO-SiO2 slag include Ca3Al4MgO10, Ca3Al2O6, and MgO. Additionally, the introduction of Ce2O3 leads to the formation of the high melting temperature CaCeAlO4 phase, whose abundance correlates positively with the Ce2O3 content. Ce2O3 demonstrates efficient bridging oxygen bond disruption, causing the transformation of network former [AlO4]-tetrahedron into network modifier [AlO6]-octahedron. Simultaneously, Q4Al shifts to Q2Al and Q3Al in [AlO4]-tetrahedron, resulting in a marked reduction in degree of polymerization of slag. This reduction is evident in decreased viscosity and melting temperature, reaching the minimum value of 0.153 Pa·s and 1331 °C, respectively. However, the Ce2O3 content is beyond 15 wt%, Q2Al and Q3Al transform into Q4Al, which lead to an upward trend in high-temperature viscosity. Furthermore, as the temperature decreases, the precipitation of the CaCeAlO4 phase from the slag occurs. The content and precipitation temperature of CaCeAlO4 increase with rising Ce2O3 content, representing the primary factor behind the elevation of low-temperature viscosity and melting temperature.

Coal gangue in asphalt pavement: A review of applications and performance influence

The comprehensive utilization of coal gangue is low, and this causes serious environment problems and security risks. The physical and chemical properties of coal gangue were analyzed in this paper, and the estimated value of different chemical components of coal gangue was counted. The physical properties of coal gangue aggregate were analyzed, and performance and its influencing factors of base course mixture with coal gangue aggregate were studied. The influence of coal gangue powder and coal gangue aggregate on performance of asphalt mortar and asphalt mixture was analyzed, and possible influencing factors and function mechanism were discussed. The results showed that heavy metal elements of coal gangue applied into asphalt pavement is not seeped out. The crushing value, water absorption and flat elongated particles content of coal gangue aggregate are generally high, but the compressive strength of base course with coal gangue aggregate is verified to meet the strength requirement. The performance, volume stability and durability of base course with coal gangue aggregate are closely related to aggregate gradation, the type and dosage of cementations materials and aggregate. The high temperature performance, temperature susceptibility and viscosity of asphalt mortar are improved by the addition of different coal gangue powder, and improvement effect of activated coal gangue powder on asphalt mortar performance is better. The low temperature performance and adhesion property of asphalt mortar with chemical activated coal gangue powder are improved. The physical reaction between asphalt and different coal gangue powder is only taken place. The temperature stability of asphalt mixture with coal gangue coarse aggregate has achieved the specification requirement. The water stability and low temperature fracture performance of asphalt mixture with fine aggregate replaced by coal gangue are improved. However, the high temperature performance of above mixture is lower than conventional hot mix asphalt mixture. The research results will provide reference for coal gangue applied into asphalt pavement.

Mixed-alkaline earth effects on the network structure and properties of alkali-free aluminosilicate glasses

Alkali-free aluminosilicate glasses with different SrO/(MgO+SrO) molar ratios were prepared by the melt-quenching method, and their structural evolution was characterized by Magic Angle Spinning Nuclear Magnetic Resonance (MAS NMR). The glass properties, including high-temperature viscosity, thermal expansion coefficient, density, Vicker hardness, elastic modulus, and chemical stability, were tested and analyzed. With the increasing of SrO/(MgO+SrO) molar ratios from 0 to1, the fraction of Q4 units in [SiO4] tetrahedral increased from 30.88 % to 39.06 %, and the Al3+ ions are dominated in [AlO4] groups, but small amount in [AlO5] units. In terms of comprehensive properties, the glass density and strain point temperature increased approximately linearly with the SrO/(MgO+SrO) ratios, while, the elastic modulus decreased with the SrO/(MgO+SrO) ratios. However, the high-temperature viscosity, Vickers hardness, chemical stability, and characteristic temperatures (melting temperature, working point temperature, Littleton softening temperature) deviated from linearity and exhibited the opposite mixed alkaline earth effect compared to previously reported aluminosilicate glasses. when the SrO/(MgO+SrO) molar ratio is approximately 0.25, the glass demonstrates optimal comprehensive performance.

Investigation of the Effect of Boron Oxide and Beeswax on Workability and High-Temperature Performance of Bitumen

AbstractIn recent years, various studies have shown that boron-containing additives improve the rutting performance of the bituminous pavements. However, in these studies, it was stated that these additives would decrease the workability of the bitumen and increase energy required for the construction of the pavement. On the other hand, it has been shown in many studies that waxes increase the workability of the bitumen. In this study, it was aimed to obtain bitumen with high rutting resistance and workability by adding boron oxide (BO) and beeswax (BW) to bitumen. Therefore, modified bitumen was produced by adding BO and BW at different ratios to a 50/70 penetration grade base bitumen. Then, the chemical, physical, and rheological properties of modified bitumen samples were investigated by various experiments. As a result, it has been observed that BO increases the high-temperature performance and viscosity of bitumen; on the other hand, BW decreases rutting resistance and viscosity. When BO and BW were added together to the bitumen, the negative impact of BO on workability and the negative impact of BW on high temperature performance were significantly eliminated. Especially, in 1BO + 1BW and 3BO + 3BW bitumens, the high-temperature performance of the bitumen improved without decreasing the workability.

Application of Intercriteria and Regression Analyses and Artificial Neural Network to Investigate the Relation of Crude Oil Assay Data to Oil Compatibility

The compatibility of constituents making up a petroleum fluid has been recognized as an important factor for trouble-free operations in the petroleum industry. The fouling of equipment and desalting efficiency deteriorations are the results of dealing with incompatible oils. A great number of studies dedicated to oil compatibility have appeared over the years to address this important issue. The full analysis of examined petroleum fluids has not been juxtaposed yet with the compatibility characteristics in published research that could provide an insight into the reasons for the different values of colloidal stability indices. That was the reason for us investigating 48 crude oil samples pertaining to extra light, light, medium, heavy, and extra heavy petroleum crudes, which were examined for their colloidal stability by measuring solvent power and critical solvent power utilizing the n-heptane dilution test performed by using centrifuge. The solubility power of the investigated crude oils varied between 12.5 and 74.7, while the critical solubility power fluctuated between 3.3 and 37.3. True boiling point (TBP) analysis, high-temperature simulation distillation, SARA analysis, viscosity, density and sulfur distribution of narrow petroleum fractions, and vacuum residue characterization (SARA, density, Conradson carbon, asphaltene density) of the investigated oils were performed. All the experimentally determined data in this research were evaluated by intercriteria and regression analyses. Regression and artificial neural network models were developed predicting the critical solubility power with correlation coefficients R of 0.80 and 0.799, respectively.

Intermediate Polymer Relaxation Explains the Anomalous Rheology of Nanocomposites with Ultrasmall Attractive POSS Nanoparticles.

The rheological properties of entangled polymers loaded with very small, strongly attractive polyhedral oligomeric silsesquioxane (POSS) fillers differ from that of nanocomposites with larger fillers by (1) the shorter breadth of the entanglement plateau and (2) the relatively unchanged terminal viscosity with increasing POSS loading. Although such anomalous rheological properties can rewrite the property-processing map of materials (e.g., high glass transition temperature and low viscosity), their mechanism remains unclear. In this study, we report that polymer relaxations on intermediate time scales between α and entire-chain relaxation, so-called "slower processes", are responsible for this unusual rheological behavior of poly(2-vinylpyridine)/octa(aminophenyl)silsesquioxane (P2VP/OAPS) nanocomposites. To uncover the effects of entanglements on the nanocomposite dynamics, rheometry is used for variable matrix molecular weights. Results show a systematic change in the rheological response, which is independent of the molecular weight, and in turn, the presence of entanglements. This supports a physical interpretation that a slower process dominates the rheological response of the material at intermediate frequencies on length scales larger than the segment length or the OAPS diameter, while the underlying physical time scales associated with the entanglement relaxation remain unchanged. Such insights are anticipated to assist the future rational design of other highly attractive and ultrasmall nanoparticles that enable a fine-tuned rheological response of nanocomposites across multiple length scales.

Viscosity experiments of slag-spinel suspensions: The effect of volume fraction, particle size, and shear rate

Heterogeneous slag viscosity measurements have a wide variety of parameters, such as particle size, shape, solid volume fraction, and shear rate, which affect the final measured viscosity. Often, some of these parameters are neglected or predicted via models, since it is experimentally difficult to determine them during high-temperature slag viscosity measurements. In this work, a viscosity apparatus was used, which allows quenching of the sample after measurement. This way, all relevant parameters could be experimentally determined. The viscosities of three datasets were studied with various spinel sizes: small (13 μm), medium (34 μm), and large particles (76 μm). Within each dataset, the composition of the liquid slag matrix was kept constant to uniquely measure the effect of solids. Shear thinning, i.e., a decreasing viscosity with increasing shear rate, was observed for all samples, even at a low vol. % of 1.8. Moreover, stronger shear thinning was observed at a higher vol. % and for smaller spinel particles. On the basis of these results, the phenomenon of shear thinning was discussed and mainly attributed to the particle–particle orientation in the suspension. The obtained viscosity values were used to optimize a Krieger–Dougherty equation, which describes the viscosity increase caused by the presence of a certain vol. % of spinel particles, with a certain size and at a specific shear rate.

Influence of lanthanides on the melt viscosity and glass density of sodium disilicate

High temperature viscosity data for 14 sodium disilicate (NS2; Na2Si2O5) melts with equimolar (5.288 mol%) additions of lanthanum oxides (Ln2O3; Ln = La; Ce; Pr; Nd; Sm; Eu; Gd; Tb, Dy; Ho; Er; Tm; Yb; Lu) have been determined in the temperature range of 1003–1490 °C. At the highest temperatures the viscosity of Ln2O3 modified NS2 generally decreases, whereas towards lower temperatures the heaviest lanthanides effect a slight increase of melt viscosity. In general, the lanthanides behave highly coherently with respect to their viscosity reducing effect, while a “tetrad effect” might be present. Two exceptions exist, Ce and Tm, both exhibiting anomalously stronger viscosity reducing effects. For Ce we attribute this behavior to its multivalent oxidation state in the melt, while for Tm its origin remains unclear. Glass densities also correlate with the atomic number, again with exceptions for Ce- and Tm-bearing samples, which exhibit the lowest and highest densities, respectively.

Comparison on the performance of solid coumarone-indene resin and liquid coumarone-indene resin modified asphalt

Coumarone-indene resin (CIR) has great potential for use as an asphalt modifier because of the cost-effective, high viscosity, and excellent mechanical properties. CIR is classified into two types based on polymerization degree: solid coumarone-indene resin (S-CIR) and liquid coumarone-indene resin (L-CIR). In this study, solid coumarone-indene resin modified asphalt (S-CMA) and liquid coumarone-indene resin modified asphalt (L-CMA) were prepared, and the comparison of the high-temperature performance, compatibility, aging performance, low-temperature performance, microstructure and modification mechanism of S-CMA and L-CMA was researched following the SuperPave standard. The results reveal that S-CIR is a solid resin with a high molecular weight that improves the high-temperature performance, permanent deformation resistance, and viscosity of asphalt, but impact on low-temperature performance negatively. In contrast, L-CIR is a liquid resin with low molecular weight that enhances the low-temperature properties and plasticity of asphalt, but decreases high-temperature properties. Additionally, solid resins with large molecular weight are prone to agglomeration in asphalt, while liquid resins with small molecular weight have better dispersibility, especially in high-content situations. Meanwhile, CIR exhibits good compatibility with asphalt. Based on the FTIR test results, chemical compositions and structures of S-CIR and L-CIR are similar, and physical miscibility was demonstrated between CIR and asphalt. In summary, modifier with different molecular polymerization degrees have a greater impact on modified asphalt, S-CMA has better high-temperature performance and viscosity than L-CMA, L-CMA has better low-temperature performance and plasticity than S-CMA, and S-CMA and L-CMA can be used for pavement construction in hot and cold areas respectively.

Mo–Ni, Mo–Fe and Mo–Ni–W nanoparticles for down-hole upgrading

Patented in situ (in reservoir) upgrading technology (ISUT) converts a portion of the reservoir into a “catalytic reactor” by irreversibly attaching a low percentage of nanoparticles to the reservoir's sand/rock. The nanoparticles are prepared as a dispersion in hot vacuum residue and the hot dispersion is injected into the reservoir with low quantities of hydrogen.MoNi, MoFe and MoNiW nanoparticles suspended in bitumen were prepared, in similar way as in ISUT, and the suspensions treated in a batch reactor. Two different sulfiding agents (ammonium sulfide and thiocarbamide) were added during the preparation of the nanoparticles-bitumen suspension. Particle diameters obtained for the suspensions were determined by NTA. The particles were recovered after reaction and its surface composition determined by XPS. Reaction products were analyzed by high temperature simulated distillation, density, viscosity, sulfur and nitrogen content and stability (P-value). MoNi, MoFe and MoNiW with average sizes of 84, 101 and 93 nm, respectively, were produced. XPS characterization of the Mo–Ni–W particles before reaction showed that Mo and Ni are only partly sulfided, while W was present as WO3. The proportion of the metals in the sulfided state increases after reaction from 39 to 94, 35 to 77 and a 0 to 50 (atomic %) for Mo, Ni and W, respectively. In addition, VR conversions were similar by comparing the thermal and catalytic tests, indicating that VR cracking is mainly thermal. However, viscosity, MCR and S contents were lower, and API gravity was higher when a catalyst was used. Also, catalytic products proved more stable than products obtained from thermal reaction. The reaction carried out using dispersions where thiocarbamide was the sulfiding agent provided products with slightly betterer properties in spite of showing larger particle diameters.

Size-dependent viscosity of silica optical fiber under high temperature

Viscosity of optical fiber plays an important role in high temperature applications in harsh environments. A size-dependent viscosity phenomenon of silica optical fiber under high temperature is observed by the stretching method with in-fiber regenerated fiber Bragg gratings (RFBGs). Higher viscosity is derived from optical fiber with larger diameters. The mechanisms of this size-dependent relationship of high temperature viscosity of silica optical fiber are discussed, and the difference in fictive temperature of silica optical fibers is considered as the mainly contribution. An equivalent fictive temperature of optical fiber at a metastable structure state is used to explain the difference in equilibrium viscosity. Then the relationship between equilibrium viscosity and fictive temperature for silica optical fiber at 1000 °C is derived.

High and intermediate temperature performance of warm asphalt rubber containing conventional warm mix additives and novel chemical surfactant

Warm mix asphalt (WMA) technology is widely used to address the workability concerns of rubberized asphalt paving materials. In this study, a novel chemical surfactant – alube– is proposed for the production of warm asphalt rubber (WAR) binders. To assess its suitability, the high and intermediate temperature performances of the resultant alube-WAR binder (AWAR) was compared with those of two conventionally produced WAR binders, namely sasobit-WAR binder (SWAR) and rediset-WAR binder (RWAR). An economic evaluation of the WAR binders was also done in order to assess their cost-competitiveness. For the high-temperature performance study, the high-temperature viscosity, viscosity-temperature susceptibility (VTS), rutting resistance, and stress sensitivity were investigated, while for the intermediate-temperature performance, the fatigue resistance factor was evaluated. Different findings were obtained from the performance and cost investigation. Alube was found to successfully lower the high temperature viscosity of AR binder but not as effective as the two conventional WMA additives. The VTS property of AR binder was only improved by the organic WMA additive (sasobit), while the chemical additives (rediset and alube) showed negative effects. In terms of rutting resistance, AWAR was superior to RWAR and AR, but was outperformed by SWAR. Also, SWAR was the least susceptible to stress changes, while AWAR and RWAR showed comparable performance. Based on the G*sin δ test, the fatigue resistance of the AR binder improved after the incorporation of the chemical additives and deteriorated after sasobit was added, and the performance ranking was determined as RWAR > AWAR > AR > SWAR. Overall, only SWAR had a better high-temperature performance than AWAR, whereas for intermediate temperature performance, only RWAR was better. Furthermore, economic analysis showed that AWAR is the most cost effective of the three WAR binders. The findings of this study indicate that alube has the potential of being utilized as a WMA additive for AR binders and can be utilized in wide range of road projects due to its cost-effectiveness.

Preparation and mechanism of rubber-plastic alloy crumb rubber modified asphalt with low viscosity and stabilized performance

Recycled rubber and plastics for asphalt modification are gaining increasing attention for sustainable pavements. However, the high viscosity and low stability of modified asphalt are the primary reasons limiting its widespread application. In this work, the rubber-plastic alloy crumb rubber (ACR) was prepared with the twin-screw extruder using crumb rubber (CR) and polyethylene (PE). The properties influence of the preparation process on ACR modified asphalt (ACRMA) was investigated by fluorescence microscopy, basic properties, and storage stability tests. The viscosity reduction characteristics of asphalt and asphalt mastic were assessed at different temperatures. Differential scanning calorimetry (DSC) and contact angle tests were used for modification mechanism analysis. Results showed that, compared with CR modified asphalt (CRMA), the thermal stability of ACRMA was improved, and its cohesion energy was not significantly reduced. The high-temperature viscosity of asphalt and its mastic was decreased by 35.1% ∼ 69.1%. But it had the same mid-temperature viscosity as CRMA. The rutting factor, high-temperature PG grade of ACRMA increased, and the phase angle decreased. The optimum dosage of PE was 15 wt% in ACR, ACR was 15 ∼ 20 wt% in asphalt, and the stabilizer was 0.05 ∼ 0.1 wt%. Compared with traditional CRMA, ACRMA with low viscosity and stabilized performance. It has good application potential, which can effectively reduce construction temperature and promote factory production.

CMAS + sea salt corrosion to thermal barrier coatings

In marine environment, sea salt and calcium-magnesium-alumina-silicate (CMAS) coexist largely endangering thermal barrier coatings (TBCs) service safety. In this study, the corrosion behavior of synthetic sea salt and CMAS to TBCs was investigated. Sea salt changed the CMAS structure, thereby decreasing its melting temperature and high-temperature viscosity. At 1200 ℃, CMAS + sea salt completely melted but CMAS did not; at 1250 ℃, both melted while CMAS + sea salt had stronger penetration ability in TBCs than CMAS. Thus, TBCs which have not been or are less affected by CMAS may be damaged due to CMAS + sea salt attack.

Predicting thermal runaway in styrene polymerization reactions: Divergence criterion with phase space reconstruction

The process of styrene polymerization is a typical hazardous chemical process. Due to its high reaction temperature and high product viscosity, it is very prone to thermal runaway accidents. In order to reduce the occurrence of such accidents, this work investigates the thermal hazard of the polymerization process by reaction calorimetry experiments and deduces the thermal runaway criterion for the styrene polymerization reaction by combining the results of gas chromatography experiments. The phase space of the system was reconstructed by the delayed coordinate method to obtain the reconstructed divergence criterion (re-div). The results showed that the exothermic heat and adiabatic temperature rise of the polymerization reaction showed a logarithmic increase with the increase of the initial reaction temperature. Compared with the div calculated by numerical method and analytical method, the analytical method div is more accurate and effective. The analytical divergence criterion (div) curve is strictly decreasing in the post-polymerization case, which indicates that it can be used as an off-line criterion to determine the safety of the reaction process by the initial reaction condition parameters. After the experimental verification, it can be confirmed that the re-div can predict whether the reaction is out of control in advance and accurately.

Combined Use of Polyurethane Prepolymer and Aromatic Oil in Physicochemical Rejuvenation of Aged SBS Modified Bitumen for Performance Recovery.

The high-quality reutilization of waste styrene-butadiene-styrene copolymer (SBS) modified asphalt mixtures is a difficult issue in the field of highways today, and the main reason is that conventional rejuvenation technology fails to achieve the effective rejuvenation of aged SBS in binder, causing significant deterioration in the high-temperature performance of the rejuvenated mixture. In view of this, this study proposed a physicochemical rejuvenation process using a reactive single-component polyurethane (PU) prepolymer as the repairing substance for structural reconstruction and aromatic oil (AO) as a common rejuvenator used to supplement the lost light fractions of asphalt molecules in aged SBSmB, according to the characteristics of oxidative degradation products of SBS. The joint rejuvenation of aged SBS modified bitumen (aSBSmB) by PU and AO was investigated based on Fourier transform infrared Spectroscopy, Brookfield rotational viscosity, linear amplitude sweep, and dynamic shear rheometer tests. The results show that 3 wt% PU can completely react with the oxidation degradation products of SBS and rebuild its structure, while AO mainly acted as an inert component to increase the content of aromatic components, thereby reasonably adjusting the compatibility of chemical components of aSBSmB. Compared with the PU reaction-rejuvenated binder, the 3 wt% PU/10 wt% AO rejuvenated binder had a lower high-temperature viscosity for better workability. The chemical reaction between PU and SBS degradation products dominated in the high-temperature stability of rejuvenated SBSmB and had a negative impact on its fatigue resistance, while the joint rejuvenation of 3 wt% PU and 10 wt% AO not only gave a better high-temperature property to aged SBSmB but could also have the capacity to improve its fatigue resistance. Compared to virgin SBSmB, PU/AO rejuvenated SBSmB has comparative low-temperature viscoelastic behavior characteristics and a much better resistance to medium-high-temperature elastic deformation.