| 摘要: |
| 利用动态黏弹力学方法,在动态剪切流变仪上通过动态黏弹试验和稳态流动试验并结合Carreau模型研究多聚磷酸(PPA)对改性沥青流变性能的影响,通过胶体组分变化和红外谱图分析探究PPA对沥青的改性机制。结果表明:在试验频率范围内,PPA改性沥青的存储模量G′ 和损失模量G″ 随频率的增加而增大,PPA掺量越大沥青的弹性性质越明显,说明PPA可有效改善沥青的模量和高温抗车辙性能;相同频率下,G′明显小于G″且模量差值随PPA掺量的增大、温度的降低及频率的增大而呈现逐渐减小的趋势;PPA的掺加使沥青的临界剪切速率c 大幅度降低,且掺量越大c越小,沥青对外部剪应力的敏感性变大;与基质沥青相比,随PPA掺量的增大,沥青胶体成分中轻组分含量减少,沥青质含量大幅增加,PPA改性沥青红外谱图中增加了1026 cm-1处的特征吸收峰(P—O单键和PO双键的伸缩振动峰),说明PPA对沥青的改性是通过发生化学反应进行的。 |
| 关键词: 流变性能 多聚磷酸 动态力学方法 改性沥青 改性机制 |
| DOI：10.3969/j.issn.1673-5005.2015.06.022 |
| 分类号::U 414 |
| 基金项目:中石油燃料油有限公司研究院与中国石油大学科研合作项目(05N13041010);中国石油大学研究生创新工程项目(15CX06046A) |
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| Rheological properties and modification mechanism of PPA modified asphalt |
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MA Qingfeng1, XIN Xue2, FAN Weiyu2, LIANG Ming2, WANG Xiaobo2
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(1.PetroChina Fuel Oil Company Limited Research Institute, Qingdao 266580, China;2.State Key Laboratory of Heavy Oil Processing, China University of Petroleum,Qingdao 266580, China)
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| Abstract: |
| With the dynamic mechanical analysis (DMA), dynamic shear test as well as steady state flow measurement which were conducted with dynamic shear rheometer (DSR) and Carreau model were used to study the effect of polyphosphoric acid (PPA) on the rheological properties and modification mechanism of asphalt. And the modification mechanism of PPA on asphalt was investigated by the changes of colloidal structure and infrared spectra. The results show that the storage moduli G′ and the loss moduli G″ increase constantly for all modified asphalts as the increase of frequency at the studied frequency region, which indicates more elastic behavior is enhanced by PPA. Consequently, PPA improves the modulus and rutting resistance of asphalt. Moreover, at the same frequency, G″ shows more pronounced than G′ and the discrepancy between G′ and G″ appears smaller as the increase of PPA content, frequency and decrease of temperature. The critical shear rate,c, decreases drastically with the addition of PPA and this trend is more significant as the increase of PPA, indicating more susceptibility to shear force. Compared to base asphalt, light components decrease in asphalt while the proportions of asphaltene increase as the increase of PPA addition. Infrared spectrum analysis shows that characteristic peak occurs at 1026 cm-1 (the emergence of P-O and P=O) in the PPA modified asphalt, which reveals PPA reacts with base asphalt. |
| Key words: rheological properties polyphosphoric acid dynamic mechanical analysis modified asphalt modification mechanism |
