多聚磷酸改性沥青改性机制

发布时间：2018-10-30 16:23

【摘要】：为了研究多聚磷酸(PPA)对沥青的改性作用,分别制备了掺量为0.5%、1%、1.5%和2%(PPA与基体沥青的质量比)的PPA改性沥青。三大指标实验结果显示,随着PPA掺量的增加,针入度减小,软化点升高,延度减小,说明在沥青中掺入PPA使沥青高温性能得到改善而低温性能略有减弱。通过四组分分析(SARA)发现随着PPA掺量的增加,沥青中的胶质逐渐减少,沥青质逐渐增多,饱和分与芳香分基本不变。利用FTIR发现,相比基质沥青,PPA改性沥青的红外光谱整体图线发生了迁移,且出现了新的吸收峰,说明PPA改性机制为化学改性。利用AFM得到基质沥青与PPA改性沥青的形貌与相位图,分析发现掺入PPA后相位图中连续相(para-phase)面积明显减小,而分散相(peri-phase)面积明显增加,且蜜蜂结构(catana-phase)谷地尺寸变大,说明掺入PPA后沥青中沥青质含量将会增多,而低温抗裂性将有所减弱。
[Abstract]:In order to study the modification effect of polyphosphate (PPA) on asphalt, PPA modified asphalt with 0.5% and 2% (mass ratio of PPA to base asphalt) was prepared, respectively. The experimental results show that the penetration decreases, the softening point increases and the ductility decreases with the increase of PPA content, which indicates that adding PPA into asphalt improves the high temperature performance and weakens the low temperature performance of asphalt. Through the four-component analysis of (SARA), it was found that with the increase of PPA content, the colloid in asphalt gradually decreased, asphaltene gradually increased, and the saturation and aromatic components were basically unchanged. It was found by FTIR that compared with the base asphalt, the infrared spectra of PPA modified asphalt migrated and a new absorption peak appeared, which indicated that the mechanism of PPA modification was chemical modification. The morphology and phase diagram of matrix asphalt and PPA modified asphalt were obtained by AFM. It was found that the area of continuous phase (para-phase) decreased and the area of dispersed phase (peri-phase) increased obviously after blending with PPA. The size of honeybee structure (catana-phase) valley becomes larger, which indicates that the asphaltene content in bitumen will increase and the cracking resistance at low temperature will be weakened after the addition of PPA.
【作者单位】：内蒙古工业大学土木学院;
【基金】：国家自然科学基金(11462018) 内蒙古自治区自然科学基金(2015 MS0539) 内蒙古交通科技项目(NJ-2014-21)
【分类号】：TE626.86

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