废胶粉/APAO复合改性沥青性能
Performance of composite modified asphalt by waste rubber powder and amorphous poly alpha olefin

为了研究废胶粉（WTR）与非晶态？？α？？？蚕┨？共聚物（APAO）对沥青复合改性的效果以及其最优加工工艺。首先采用高速剪切法制备多组不同掺量的WTR/APAO复合改性沥青；然后测定WTR/APAO复合改性沥青的针入度、软化点、黏度、弹性恢复，同时进行了存储稳定性分析与荧光显微镜微观检测；最后通过正交试验确定WTR/APAO复合改性沥青最优加工工艺。研究结果表明：WTR与APAO的掺量（质量分数,下同）分别为15%与4%时，WTR/APAO复合改性沥青的针入度比基质沥青降低了36.8 mm,软化点增加了22.9 ℃，弹性恢复增加了67%，黏度（180 ℃）增加81%，且其各项指标均满足橡胶沥青评价指标要求；加入适量的WTR与APAO后基质沥青的高温性能和可恢复变形能力得到明显提高，WTR/APAO复合改性沥青具有较好的改性效果；与WTR单独改性相比，加入APAO能使针入度进一步减小，软化点、黏度与弹性恢复进一步增加，APAO的加入能进一步提升WTR的改性效果；加入4%的APAO后，WTR/APAO复合改性沥青比仅掺入15%的WTR改性沥青的软化点降低了3.3 ℃，APAO的加入能显著提高废胶粉改性沥青的存储稳定性，弥补了废胶粉改性沥青的不足；APAO不仅增进了WTR的分散程度，而且改善了WTR与沥青相的相容性。WTR/APAO复合改性沥青最优加工工艺基本参数为：先加入WTR，后加入APAO，控制剪切温度？？190 ℃？？，剪切时间90 min,剪切速度5 000 r/min。
In order to study the influence of waste rubber powder (WTR) and amorphous poly alpha olefin (APAO) on composite modified asphalt and its optimum processing technology, multiple groups of blending quantity of WTR/APAO composite modified asphalt were prepared by using high？？speed shearing method at first, then the penetration, softening point, viscosity and elastic recovery of WTR/APAO composite modified asphalt were measured, and simultaneously, the storage stability analysis and microscopic examination of fluorescence microscope were carried out. Finally, the optimum processing technology of WTR/APAO composite modified asphalt was determined by orthogonal test. The results show that when the blending quantity of waste rubber powder and APAO (mass fraction, the same below) is 15% and 4%, respectively, the penetration of WTR/APAO composite modified asphalt is lower than that of matrix asphalt by 36.8 mm, the softening point increases by 22.9 ℃, the elastic recovery increases by 67%, and the viscosity (180 ℃) increases by 81%. And all indexes meet the requirements of the evaluation index of rubber asphalt. This indicates that after adding appropriate amount of WTR and APAO, high temperature performance and recoverable deformation ability of matrix asphalt are significantly improved, and WTR/APAO composite modified asphalt has better modification effect. Moreover, compared to WTR modification alone, the addition of APAO can result in a further decrease in penetration and a further increase in softening point, viscosity and elastic recovery, the addition of APAO can further enhance the effect of WTR modification alone. The storage stability experiment reveals that the softening point difference of WTR/APAO composite modified asphalt decreases by 3.3 ℃ compared to waste rubber powder modified asphalt with the blending quantity of 15% alone after adding 4% APAO, which proves that the addition of APAO can