Wei Li, Li Linxianzi, Liang Mingmei, Rong Hongliu, Yang Xiaolong
College of Architecture and Civil Engineering, Nanning University, Nanning 541699, China.
College of Civil Engineering and Architecture, Guangxi University, Nanning 530004, China.
Polymers (Basel). 2024 Sep 30;16(19):2766. doi: 10.3390/polym16192766.
To enhance the service life of traditional asphalt pavement and mitigate issues such as high-temperature rutting and low-temperature cracking, this study investigates the composite modification of matrix asphalt using thermoplastic polyurethane (TPU) and styrene-butadiene rubber (SBR). Initially, the study examines the conventional properties of the composite-modified asphalt from a macro perspective, analyzing the performance variations of asphalt before and after TPU and SBR modification. Subsequently, microscopic analysis is conducted to explore the microstructure, phase structure, and modification mechanisms of the composite-modified asphalt, with a focus on understanding the underlying reasons for performance changes. The influence of TPU and SBR on asphalt performance is evaluated comprehensively. It is found that TPU-modified asphalt demonstrates superior high-temperature performance, storage stability, and elastic recovery. Conversely, SBR-modified asphalt excels in ductility at low temperatures, though its storage stability decreases with increasing dosage. Based on a thorough analysis of the conventional properties of the two types of modified asphalt, the optimal dosages of TPU and SBR are determined to be 15% and 3.5%, respectively. In the composite-modified asphalt, TPU facilitates the even distribution of chemical components, creating a more stable cross-linked network structure. The compatibility of TPU, SBR, and asphalt contributes to the good storage stability of the composite-modified asphalt. While SBR effects physical modification, TPU induces chemical modification of asphalt. Consequently, the composite modification system benefits from both physical and chemical enhancements, resulting in excellent overall performance.
为提高传统沥青路面的使用寿命，减轻高温车辙和低温开裂等问题，本研究探讨了采用热塑性聚氨酯（TPU）和丁苯橡胶（SBR）对基质沥青进行复合改性。首先，该研究从宏观角度考察了复合改性沥青的常规性能，分析了TPU和SBR改性前后沥青的性能变化。随后，进行微观分析以探究复合改性沥青的微观结构、相结构和改性机理，重点是理解性能变化的潜在原因。综合评估了TPU和SBR对沥青性能的影响。结果发现，TPU改性沥青具有优异的高温性能、储存稳定性和弹性恢复性能。相反，SBR改性沥青在低温下的延展性较好，但其储存稳定性随用量增加而降低。基于对两种改性沥青常规性能的深入分析，确定TPU和SBR的最佳用量分别为15%和3.5%。在复合改性沥青中，TPU促进了化学成分的均匀分布，形成了更稳定的交联网络结构。TPU、SBR与沥青的相容性有助于复合改性沥青具有良好的储存稳定性。SBR起到物理改性作用，而TPU引发沥青的化学改性。因此，复合改性体系兼具物理和化学增强效果，整体性能优异。
