溶解性胶粉改性沥青的制备及其流变性能

Rheological Properties and Preparation of Devulcanized and Pyrolytic Crumb Rubber Modified Asphalt

摘要:

针对普通胶粉改性沥青（CRMA）和目前大部分溶解性胶粉改性沥青（DCRMA）制备工艺中存在的不足，提出了一种快速制备DCRMA的方法.采用针入度、软化点和旋转黏度为性能控制指标，优化了制备工艺参数，并进一步分析了DCRMA的技术特性和流变性能.结果表明：发育和剪切时间分别为4h和2h，制备温度为220℃为适宜的DCRMA制备工艺参数；添加15%胶粉的溶解性胶粉改性沥青（15DCRMA）的胶粉溶解度达到90.04%；DCRMA比CRMA具有更高的弹性恢复率和低温延度；相同胶粉掺量下，DCRMA较CRMA具有更优的低温性能；增加胶粉掺量可以进一步改善DCRMA的低温性能，但会降低其高温性能；15CRMA、15DCRMA和20DCRMA的PG分级结果分别是PG7614、PG7618和PG7022；3种胶粉改性沥青均不适用于时温等效原理.

Abstract:

A method for preparing devulcanized and pyrolytic crumb rubber modified asphalt(DCRMA) was proposed to overcome the shortcomings of common crumb rubber modified asphalt(CRMA) and most of the existing preparation technology of terminal blend crumb rubber modified asphalt. The preparation process parameters were determined in terms of performance indices of penetration, softening point and rotational viscosity, and the technical characteristics and rheological properties of DCRMA were analyzed through laboratory tests. The results show that the processing parameters of DCRMA are 4 h and 2 h for development and shearing, and 220℃ for preparation processing; the solubility of 15DCRMA achieves 90.04%; DCRMA shows a higher elastic recovery rate and lower temperature ductility than that of CRMA; DCRMA exhibits better low temperature performance than CRMA under the same crumb rubber content; the low temperature performance of DCRMA is improved due to the increasing content of crumb rubber, but the corresponding high temperature resistence of DCRMA is lowered; the PG temperatures of 15CRMA, 15DCRMA and 20DCRMA are PG76 14, PG76 18 and PG70 22, respectively; the time temperature superposition cant be employed in the three kinds of crumb rubber modified asphalt.