Journal of the Korean Asphalt Institute ISSN:2234-0785(Print) 2635-9553(Online) 한국아스팔트학회지

Asphalts were mixed with polyphosphoric acid(PPA.) to compensate the softening point deficiency of dimethylphenol-modified asphalt. Then five agents(EG, PEG, DEA, TEA, TETA) were added to the mixed asphalts to see the effect of antistripping effect of the agents. PPA with the agents increased the tensile strength of the asphalts and enhanced the softening points except TETA with. Penetration test shows that PPA. and the all agents together softened the asphalts. In the stripping experiments these asphalts were applied to two kinds of aggregate: one was granite which is acidic and the other was limestone which is basic. They are apparently all effective for antistripping of both aggregates. However when the residue rate is concerned they are only effective for granite. The reason may be they have opposite electrical charges each other, that is, all agents are basic(© charge) and the granite is acidic(© charge), so they electrically attract each other. In the case of granite the antistripping effect didn’t follow the pKa rule of agents. Rather the effect followed the intermolecular force occurring between the surface of aggregate and the functional groups of the agent.