Low‐density polyethylene/silica compound modified asphalts with high‐temperature storage stability

Low‐density polyethylene (LDPE) modified asphalts with improved high‐temperature storage stability are prepared by incorporating silica into the LDPE compounds. The effect of silica on the high‐temperature storage stabilities, dynamic rheological and mechanical properties, and morphologies of the modified asphalts are studied. It is found that the LDPE/silica ratio in the compound has a great effect on the high‐temperature storage stability. The modified asphalts are stable when the ratio of LDPE/silica is around 100/60 (w/w). The silica content in the modified asphalts is less than 3.2%, and it has a slight influence on the mechanical properties of the modified asphalts. Silica can improve the rheological properties of the modified asphalt to some extent. The high‐temperature storage stability can be increased by a decreasing density difference between the LDPE/silica compound and the asphalt or in terms of equalizing the polarity differences between asphalt and LDPE by silica.