甲基丙烯酸缩水甘油酯接枝低密度聚乙烯沥青改性剂改性机理研究

分别用低密度聚乙烯(LDPE)以及甲基丙烯酸缩水甘油酯接枝低密度聚乙烯(GMA-g-LDPE)对中海36-1基质沥青进行改性,研究了软化点、低温延度以及高温储存稳定性随着改性剂含量变化而变化的规律.通过动态剪切流变试验(DSR)和弯曲梁流变试验(BBR)测试表明,GMA-g-LDPE改性中海36-1基质沥青的高温、低温性能分别优于LDPE改性中海36-1基质沥青.通过荧光光学显微镜观察发现,两种改性沥青的相态区别较大.两种改性沥青与基质沥青的FTIR比较显示,不同吸收峰有一定的变化, GMA-g-LDPE改性中海36-1基质沥青的FTIR验证了GMA-g-LDPE中的环氧基团与沥青体系中官能基团发生了反应.研究推断,GMA-g-LDPE与中海36-1基质沥青之间形成的网络结构导致了GMA-g-LDPE改性中海36-1基质沥青的性能优于LDPE改性中海36-1沥青.

RESEARCH OF MECHANISM OF GMA-G-LDPE MODIFIED ZHONGHAI 36-1 ASPHALT

The Zhonghai36-1 asphalt modified by LDPE and GMA-g-LDPE was studied respectively and the changing rules of softening point, ductility in low temperature and storage stability in high temperature with variations of modification agent contents. The DSR and BBR tests demonstrate that the GMA-g-LDPE-modified asphalt has better performances of rutting resistance in high temperature and fatigue resistance in low temperature than those of LDPE-modified asphalt. The fluorescent microscopy indicates that the differences are greater between phase states of the two modified asphalts. Compared to FTIR of the base asphalt, the changing of different absorption peak in FTIR of two kinds of modified asphalts exists, and the changing of FTIR of GMA-g- LDPE-modified asphalt confirms that the epoxy group in GMA-g-LDPE reacts with functional group in asphalt. It is deduced that the network between the asphalt and GMA-g-LDPE results in the better performances of GMA-g-LDPE-modified asphalt than that of LDPE modified asphalt.