المؤلفون: Zhang, Wenxuan^1,2 (AUTHOR), Li, Qiang¹ (AUTHOR) liqiang2526@njfu.edu.cn, Wang, Jiaqing^1,3 (AUTHOR), Zeng, Xianhui¹ (AUTHOR), Yu, Bin² (AUTHOR)

المصدر: Construction & Building Materials. May2024, Vol. 428, pN.PAG-N.PAG. 1p.

مصطلحات موضوعية: *ASPHALT, *ASPHALT modifiers, *DYNAMIC stability, *TENSILE tests, *INFRARED spectroscopy, *MIXTURES

مستخلص: In order to evaluate the effects of three preparation processes, namely dry process (DP), wet process (WP) and wet/dry mixing process (MP), and resin high viscosity modifier (RHVM) on the road performance of porous asphalt mixtures, the frequency scanning, multi-stress creep recovery, and bending beam rheometer tests were used to analyze the rheological performance of resin-modified high viscosity asphalt under different processes. Uniaxial compression, Wheel tracking, Semi-circular bending and Freeze-thaw indirect tensile tests were used to test the properties of resin-modified porous asphalt mixtures under different processes. The commonly used TAFPACK-Super (TPS) modifier was a control group. Finally, the changes in the microscopic morphology characteristics and chemical composition were used to illustrate the enhancement mechanism of resin modifiers. The results showed that the high-temperature deformation resistance and low-temperature cracking resistance of RHVM modified asphalt prepared by DP and MP are weaker than that of the WP. Compared to the RHVM(WP), the J nr (3.2) of RHVM(DP) and RHVM(WP) decreased by 14.3 % and 63.8 %, the strength modulus of RHVM(DP) and RHVM(MP) increased by 21.5 %, 28.0 % and the creep rate decreased by 2.37 %, 4.45 %, respectively. As for the performance of asphalt mixture, compared to the RHVM(WP) asphalt mixture, the dynamic stability of RHVM asphalt mixture prepared by the DP and MP decreased by 17.3–18.2 %, σ s and ε s of RHVM(DP) and RHVM(MP) increased by 15–35 % and 21–29 %, respectively. The water stability of RHVM(DP) asphalt mixtures was better than that of RHVM(WP) when the mixing time reached 180 s. RHVM(WP) asphalt mixtures have superior low-temperature cracking resistance, comparable water stability, and slightly poorer high-temperature stability than that of TPS(WP) asphalt mixture. Microscopic morphology observation found that some modifier particles and asphalt binder did not realize effective mixing under the DP and MP, and infrared spectroscopy results confirmed that TPS modifiers are mainly physically co-mingled with asphalt, while the tackifier resin in the RHVM reacts with the asphalt to form new functional groups to increase the viscosity of the asphalt. • The road performance of resin porous asphalt mixtures under dry, wet and dry-wet mixed processes was evaluated. • The rheological performance of resin modified high viscosity asphalt extracted from dry, wet and dry-wet mixed process asphalt mixture was evaluated. • The modification mechanism of resin high viscosity modifiers on asphalt was discovered. [ABSTRACT FROM AUTHOR]

المؤلفون: Xu, Xiong^1,2 (AUTHOR), Chu, Yaming^1,2 (AUTHOR), Luo, Yi^1,2 (AUTHOR), Peng, Yuhao^1,2 (AUTHOR), Yang, Nannan^1,2 (AUTHOR), Yan, Jiaming^1,2 (AUTHOR), Chen, Xuyong^1,2 (AUTHOR) Chenxy@wit.edu.cn, Zou, Fuliao^1,3,4 (AUTHOR) fu-liao.zou@connect.polyu.hk, Sreeram, Anand^1,5 (AUTHOR) as3374@cam.ac.uk

المصدر: Journal of Cleaner Production. Nov2023, Vol. 426, pN.PAG-N.PAG. 1p.

مصطلحات موضوعية: *WASTE recycling, ASPHALT modifiers, ASPHALT, CRUMB rubber, MALEIC anhydride, POLYPROPYLENE, DICUMYL peroxide

مستخلص: Polypropylene (PP) wastes do not easily mix with asphalt binder to reach a uniformly dispersed phase at a regular blending temperature as a result of its very high melting temperature and molecular nonpolar properties. With considering their use in asphalt applications, the melting temperature needs be reduced, together with improved polymer-asphalt compatibility using effective treating approaches. Therefore, this study proposes an innovative thermal-and-mechanochemical method to efficiently convert waste PP into maleated-epoxided degradation products as warm-mix asphalt modifiers (PPMs) through hybrid use of dicumyl peroxide (DCP), maleic anhydride (MAH), and epoxidized soybean oil (ESO), for modification and property enhancement of virgin binder. The modified asphalt (PPMA) binders with different treated PPMs and untreated PPM were prepared at blending temperatures of 140∼170 °C and 170–180 °C, respectively. Further, the viscosity, softening point, ductility, storage stability, and micro-morphology tests were characterized for the prepared PPM modified asphalts (PPMAs), while torque rheology, melt flow rate (MFR), thermogravimetric analysis (TGA), and Fourier transform infrared (FTIR) spectra were measured for these PPMs, in order to analyze the performance improvement and cleaner production mechanisms. The results showed that the collective use of DCP, MAH, and ESO can cause a series of chemical reactions, including degradation and grafting, to PPM0 for the generation of maleated-epoxided degradation products with lower thermal stability and higher melt fluidity under thermal-and-mechanochemical treatment. Optimally, the maleated-epoxided PPM containing 5% ESO reduces the softening point difference of virgin binder by almost 70% due to the improved the modifier-asphalt compatibility, and its storage stability, softening point and viscosities are most improved. Overall, the designed processing method can promote waste PP to be upcycled into maleated-epoxided degradation products that can be used as warm-mix performance-enhancing modifiers. • Waste PP can be mechanochemically upcycled into a warm-mix asphalt modifier. • The modifier can be mixed into asphalt binder at lower temperatures. • The modifier can improve overall properties of virgin bitumen. [ABSTRACT FROM AUTHOR]

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المؤلفون: Sun, Xiaolong¹ (AUTHOR), Peng, Qinyuan¹ (AUTHOR), Zhu, Yongqiang² (AUTHOR), Chen, Qian³ (AUTHOR), Yuan, Junshen¹ (AUTHOR), Zhu, Yunchu¹ (AUTHOR)

المصدر: Advances in Materials Science & Engineering. 7/7/2022, p1-12. 12p.

مصطلحات موضوعية: *ASPHALT, *ASPHALT modifiers, *ASPHALT testing, *POLYMERS, *SCANNING electron microscopes, *ULTRAVIOLET radiation, *RHEOLOGY

مستخلص: The purpose of this study was to characterize and evaluate the effects of UV radiation on the rheological and physicochemical properties of ASA polymer-modified asphalt. The conventional properties (penetration, softening point, ductility, and Brookfield viscosity) of ASA polymer-modified asphalt were tested. Based on rheology, the effect of different UV irradiation times on the high-temperature performance of ASA polymer-modified asphalt was systematically characterized, the thermogravimetric analyzer (TGA) was used to analyze thermogravimetric properties of ASA polymer-modified asphalt, and the micromorphological characteristics of ASA-modified asphalt under different UV irradiation times were characterized by scanning electron microscope (FIB-SEM). The results show that the ASA polymer has a significant effect on the basic properties of asphalt. Compared with the base asphalt, the high-temperature stability of the modified asphalt was decreased, and the low-temperature ductility performance was improved. ASA polymer can effectively reduce the aging effect of ultraviolet radiation on the base asphalt and inhibit the generation of microcracks. ASA polymers improve the thermal stability of asphalt binders. During the aging process, the formation of carbonyl and sulfoxide groups was inhibited, indicating that ASA polymer can effectively delay the UV aging of asphalt. [ABSTRACT FROM AUTHOR]

المؤلفون: Gui, Wanmei¹ (AUTHOR) guiwanmei_0620@126.com, Liang, Li¹ (AUTHOR) ll-neu@163.com, Wang, Lan² (AUTHOR) 20210000034@imut.edu.cn, Zhang, Fei² (AUTHOR)

المصدر: Materials (1996-1944). Jul2022, Vol. 15 Issue 13, p4389-N.PAG. 18p.

مصطلحات موضوعية: *ASPHALT modifiers, *ASPHALT, *ASPHALT pavements, *THERMAL stresses, *RUBBER, *SUPERPOSITION principle (Physics), *CRITICAL temperature

مستخلص: Warm-mix asphalt technology has been applied to recycled rubber asphalt binder (RAB), which forms warm-mixed crumb rubber-modified asphalt binder (W-RAB) as a "green" material for environmental conservation and to enhance road performance. Furthermore, low-temperature cracking is one of the major distresses for asphalt pavement, which drastically restricts ride quality and service level. Therefore, the main objective of this study is to comparatively analyze the low-temperature properties of W-RABs based on thermal stress and the simple fractional model. W-RABs were obtained by mixing 60 mesh recycled rubber (CR) and two different types of warm-mix additives, namely viscosity reducer (1, 2, and 3%) and surfactant (0.4, 0.6, and 0.8%). First, Hopkins and Hamming's numerical algorithm and the Boltzmann superposition principle were used for obtaining thermal stress σ T . Subsequently, critical cracking temperature T c r was derived using the single asymptote procedure (SAP) theory. Second, the simple fractional viscoelasticity model was used to calculate the creep compliance, damping ratio, and dissipation energy ratio, and the results were compared with the Superpave protocol results obtained with bending beam rheometer (BBR) tests. The results showed that a combination of CR and warm-mix additives could slightly improve the thermal crack resistance of the asphalt binder. The addition of 0.6% surfactant yielded the optimum performance, while only a high dosage (3%) of viscosity reducer provided a marked improvement in efficiency, which decreased with a decrease in temperature. This study recommends the use of RAB composited with 0.6% surfactant for areas with extremely low temperature. [ABSTRACT FROM AUTHOR]

المؤلفون: Ghanoon, Seyed Alireza¹ St_ar_ghanoon@azad.ac.ir, Tanzadeh, Javad² Tanzadeh@iaubanz.ac.ir, Khodaparast, Mehdi¹ Mehdi.khodaparast88@gmail.com, Shahrezagamasaei, Reza³ Reza_shahrezagamasaei@yahoo.com

المصدر: International Journal of Pavement Research & Technology. Jul2022, Vol. 15 Issue 4, p899-914. 16p.

مصطلحات موضوعية: *ASPHALT modifiers, *ASPHALT, *DEFORMATIONS (Mechanics), *NANOSTRUCTURED materials, *ELASTICITY

مستخلص: The present study was conducted to specifically evaluate performance of asphalt binder modified by polymers and nanomaterial additives. Nano-silica, EVA (ethylene-vinyl-acetate copolymer), and SBS (styrene-butadiene-styrene) were used as asphalt binder modifiers against permanent deformation. Multiple stress creep-recovery (MSCR) tests were performed to scrutinize resistance of the asphalt binder to rutting at three temperatures of 58, 64, and 70 °C. In the MSCR test, non-linear properties of asphalt binder were assessed. In this paper, three critical parameters of non-recoverable creep compliance (Jnr), recovery creep percentage (R%), and the difference between non-recoverable creep compliance at high and low stresses (Jnrdiff) were measured. Besides, loading capacity of the modified asphalt binder was evaluated. The results represented that addition of EVA, SBS, and nano-silica increased rutting resistance and also delayed elasticity. In addition, it was observed that addition of these additives as a modifier to asphalt binder leads to the increased traffic loading grades. In improving the non-recoverable creep compliance parameter, the best performance was related to EVA, SBS, and nano-silica, respectively. In improving the recovery creep percentage, the procedure was the same and EVA had the best performance, with the difference that in this parameter nano-silica performed better than SBS. It was also found that 6% of nano-silica could bring performance of PG 58-22 closer to PG 64-22 asphalt binder. [ABSTRACT FROM AUTHOR]

المؤلفون: Peifeng Cheng¹, Zhanming Zhang¹ zhanming974@163.com, Zonghao Yang¹, Yiming Li¹

المصدر: International Journal of Pavement Research & Technology. Jul2022, Vol. 15 Issue 4, p876-888. 13p.

مصطلحات موضوعية: *ASPHALT modifiers, *SELF-healing materials, *ASPHALT, *FOURIER transform infrared spectroscopy, *GEL permeation chromatography, *ELECTRON microscopes

مستخلص: To evaluate and compare the self-healing properties of asphalt with different nano-montmorillonite (MMT) additions and from explaining the self-healing mechanism, the self-healing properties of base asphalt and Styrene Butadiene Styrene (SBS) modified asphalt with different MMT additions were tested using accompanying rest-time Dynamic Shear Rheometer (DSR) time-sweep test. Brookfield rotational viscosity test, sweeping electron microscope test, sessile drop test, Fourier transform infrared spectroscopy test, and gel permeation chromatography test were used to analyze the self-healing mechanism of the asphalt binder. Then, these indexes were correlated with the self-healing performance. The results showed that there were significant differences between the self-healing performance of base asphalt and SBS-modified asphalt binder. The intercalation structure formed by MMT in the binder increased the content of methylene and macromolecules, and increased the viscosity and surface free energy of the binder, thus increasing the active healing performance. [ABSTRACT FROM AUTHOR]

المؤلفون: Singh, Bhupendra¹ bhupendra@iitj.ac.in, Kumar, Praveen² pkaerfce@iitr.ac.in

المصدر: International Journal of Pavement Research & Technology. Jul2022, Vol. 15 Issue 4, p789-802. 14p.

مصطلحات موضوعية: *ASPHALT modifiers, *ASPHALT, *STRAINS & stresses (Mechanics), *FLEXIBLE pavements, *FATIGUE cracks

مستخلص: Rutting and fatigue are two major pavement distresses which affect both structural and functional performances of the flexible pavement. Linear amplitude sweep (LAS) and Multiple stress creep and recovery (MSCR) are two advanced methods to examine fatigue and rutting performance of asphalt binders respectively. The present study aims at examining the effect of ageing (short term and long term) and modification (polymer and warm mix) on the performance of asphalt binders. Both LAS and MSCR tests were conducted at different temperatures, stress/strain levels, and ageing conditions. Stress is a parameter that influences the performance of asphalt binder significantly so stress susceptibility was also evaluated for all the binders at different temperatures and ageing conditions. From the test results, it was found that ageing improves the stress susceptibility of the asphalt binders with respect to rutting parameters on the other hand ageing deteriorated the stress susceptibility concerning fatigue parameters. The applicability of different asphalt binders at different temperature and traffic conditions was also examined and it was found that most of the binders failed to fulfill the criteria at the temperatures which were well below their high-temperature performance grades. This highlighted the need to revise the Superpave criteria. [ABSTRACT FROM AUTHOR]

العنوان البديل: Develop and study on performance about ESO compatibilized crumb rubber-plastic modified asphalt.

المؤلفون: 曹雪娟¹ 55901658@qq.com, 张翰琳¹, 易柳¹, 邓梅¹

المصدر: Applied Chemical Industry. Jul2022, Vol. 51 Issue 7, p2020-2024. 5p.

مصطلحات موضوعية: *RUBBER powders, *ASPHALT modifiers, *SOY oil, *ASPHALT, *COMPATIBILIZERS, *NITRILE rubber, *PLASTIC products manufacturing

الملخص (بالإنجليزية): The wet process was used to prepare crumb rubber-plastic modified asphalt. The effect of the epoxy soybean oil(ESO) content on the properties of modified asphalt were studied・ The ESO and aromatic oil were used as co・solvent respectively, the effects of the two in improving the compatibility of asphalt were compared and analyzed・ The results showed that the addition of ESO improve the dispersion effect of rubber and plastic modifier in asphalt, and the low temperature properties of modified asphalt was gready improved, and the storage stability is greatly improved・ The orthogonal test results showed that the rubber powder content is the main factor affecting the properties of rubber-plastic modified asphalt. The best preparation process is: rubber powder 25%, LDPE 4%, ESO 2%, shearing time 1.5 h・ In addition, under the optimal preparation process, the compatibilizing effects of the two compatibilizers were similar・ Considering cost and environmental protection factors, epoxy soybean oil can replace aromatic oil as compatibilizing agent of rubber-plastic modified asphalt. [ABSTRACT FROM AUTHOR]

Abstract (Chinese): 用湿法制备废旧橡塑改性沥青, 研究环氧大豆油掺量对改性沥青性能的影响。结果表明, 随着环氧大豆 油掺量增加, 橡塑改性剂在沥青中的分散效果更好, 改性沥青低温性能大幅度提升, 储存稳定性大幅度提升。正交 实验结果表明胶粉掺量是影响橡塑改性沥青性能的主要因素,其最佳制备方案为:橡胶粉25%, LDPE 4%, 环氧大 豆油2%, 剪切时间1.5 hQ芳桂油与环氧大豆油改善沥青相容性的增容效果相近, 芳桂油对橡塑沥青低温性能的 提升略优于环氧大豆油, 但环氧大豆油成本更低、更环保, 可替代芳桂油作为橡塑改性沥青的增容剂. [ABSTRACT FROM AUTHOR]

المؤلفون: Zhou, Gang¹ (AUTHOR) cjhs_2000@163.com, Li, Chuanqiang² (AUTHOR) wanghaobopostbox@163.com, Wang, Haobo² (AUTHOR) lzzengwei@163.com, Zeng, Wei² (AUTHOR), Ling, Tianqing¹ (AUTHOR) lingtq@163.com, Jiang, Lin¹ (AUTHOR) jianglin_cn@foxmail.com, Li, Rukai¹ (AUTHOR) lirukai89@163.com, Liu, Qizheng¹ (AUTHOR) liuqizheng_cn@163.com, Cheng, Ying¹ (AUTHOR) chengying_cn@163.com, Zhou, Dan¹ (AUTHOR) zhoudan_cn1@163.com

المصدر: Materials (1996-1944). Jun2022, Vol. 15 Issue 12, p4346-N.PAG. 14p.

مصطلحات موضوعية: *ASPHALT modifiers, *ASPHALT, *PLASTIC scrap, *POLYPROPYLENE, *RHEOLOGY, *FREE surfaces, *RAW materials

مستخلص: The production of high-performance, low-cost warm mix additives (WMa) for matrix asphalt remains a challenge. The pyrolysis method was employed to prepare wax-based WMa using waste polypropylene plastic (WPP) as the raw material in this study. Penetration, softening point, ductility, rotational viscosity, and dynamic shear rheological tests were performed to determine the physical and rheological properties of the modified asphalt. The adhesion properties were characterized using the surface free energy (SFE) method. We proved that the pyrolysis temperature and pressure play a synergistic role in the production of wax-based WMa from WPPs. The product prepared at 380 °C and 1.0 MPa (380-1.0) can improve the penetration of matrix asphalt by 61% and reduce the viscosity (135 °C) of matrix asphalt by 48.6%. Furthermore, the modified asphalt shows favorable elasticity, rutting resistance, and adhesion properties; thus, it serves as a promising WMa for asphalt binders. [ABSTRACT FROM AUTHOR]

المؤلفون: Li, Sheng¹ (AUTHOR) lishengttt@163.com, Sun, Yu² (AUTHOR) s17392231107@163.com, Fang, Shuo³ (AUTHOR) 13142277015@163.com, Huang, You² (AUTHOR) huanan.yu@csust.edu.cn, Yu, Huanan² (AUTHOR), Ye, Ji⁴ (AUTHOR) sy164798189@163.com

المصدر: Materials (1996-1944). Jun2022, Vol. 15 Issue 12, p4172-N.PAG. 14p.

مصطلحات موضوعية: *PRINTED circuits, *ASPHALT modifiers, *FOURIER transform infrared spectroscopy, *ASPHALT, *ELECTRONIC waste, *SCANNING electron microscopes, *ASPHALT pavements

مستخلص: Non-metallic fractions (NMFs) from waste printed circuit boards (PCBs) are mostly composed of cured resin and fiber. In this study, NMF material from a PCB was ground into powder and added into matrix asphalt to produce PCB-NMF-modified asphalt. To improve the compatibility of PCB-NMF and asphalt, a compatibilizer consisting of tung oil and glycerol was also developed. The optimum compatibilizer content was determined to be 8% by weight of the PCB-NMF through a series of laboratory tests, including the softening point, penetration, ductility, and softening point difference (SPD). The micro-mechanism of NMF powder-modified asphalt was analyzed through Fourier transform infrared spectroscopy (FTIR) and a scanning electron microscope test (SEM). The performances of PCB-NMF-modified asphalt were evaluated by the dynamic shear rheology (DSR) test and the low-temperature bending beam rheometer (BBR) test. The optimum compatibilizer content was 8% by weight of the NMF powder and the optimum content of NMF powder was determined to be 30% by weight of the asphalt based on a comprehensive evaluation. The results show that PCB-NMF can significantly improve stiffness, rutting resistance, high-temperature stability, and temperature sensitivity of asphalt material at an appropriate content. The BBR tests revealed that PCB-NMF slightly weakened the cracking resistance of asphalt at low temperatures. The SEM test showed that the addition of a compatibilizer can increase the compatibility by making the NMF powder evenly dispersed. The FTIR test results implied that a chemical reaction may not have happened between PCB-NMF, compatibilizer, and the matrix asphalt. Overall, it is a promising and sustainable way to utilize PCB-NMF as a modifier for asphalt material and reduce electronic waste treatment at a low cost. [ABSTRACT FROM AUTHOR]