Modified Chitosan as a “Multi‐subtype” Macromolecular Emulsifier for Preparing Asphalt Emulsion

Abstract

The “Multi‐subtype” macromolecular cationic asphalt emulsifier was synthesized based on chitosan (abbreviated as MCTS) via the ring‐opening reaction and quaternization. Then the structure of the emulsifier was characterized by FTIR and 1H‐NMR spectra. Moreover, the surface tension and critical micelle concentration (CMC) of the MCTS were determined from 298 to 313 K. The CMC and γcmc were 0.064 g L−1 and 38.85 mN m−1 at 298 K, respectively, and the lowest surface tension of the solution reached to 26.09 mN m−1 at 313 K. The tested Hydrophile‐Lipophile Balance (HLB) value of MCTS was 10, which can meet the requirement of asphalt emulsifier. Through emulsification experiments, the emulsifying ability of the MCTS was measured, and the results indicated that the emulsifier exhibited excellent application for asphalt. It may be caused by that the MCTS containing polar bundle groups could enhance the interaction between polar asphaltene and the emulsifier solution. Moreover, the prepared asphalt emulsion was more stable compared to the emulsion prepared by Gemini emulsifier. The demulsification experiments were also correspondingly done for emulsified asphalt. All the results showed that the MCTS has potential applications in the preparation of asphalt emulsion.

Optimizing Performance Asphalt Concrete Hot Rolled Sheet– Wearing Course (HRS-WC) Using Chitosan Powder

“…The shells of marine animals containing chitin are deacetylated, which eventually becomes chitosan. Chitosan is used to increase the viscosity and stability by forming a dense network [8] [9]. Hou reinforces this, Wang who researched chitosan as an asphalt emulsifier, showing that chitosan can increase the viscosity of asphalt emulsions without adverse effects on stability [8].…”