Study On The Anionic Emulsifier With High Dispersancy And Its Application On The Cement Asphalt System

In this paper, three new types of anionic surfactants, with the properties of emulsifying asphalt and reducing water, were prepared. They were modified by methylnaphthalene sulfonate formaldehyde condensate, and used to emulsify the matrix asphalt and prepare the cement asphalt mortar. The main contents are listed as follows:The sulfonation of methylnaphthalene and the condensation of methylnaphthalene sulfonic acid-formaldehyde were studied systematically. The types of methylnaphthalene, the mole ratio of methylnaphthalene to sulfonic acid, the reaction temperature and time were investigated through orthogonal experiment, and it came to a conclusion that the composition and performance of the products were greatly affected by the type of methylnaphthalene and the amount of the sulfonic acid. Then different mole ratios of methylnaphthalene sulfonic acid to formaldehyde in the condensate reaction were investigated. The best experimental conditions for preparing methylnaphthalene sulfonate formaldehyde condensate, with the best emulsifying property, were finally determined.The new asphalt emulsifiers were obtained by bringing three types of hydrophobic groups into the basic methylnaphthalene sulfonate formaldehyde condensate structure. To be specific, polyoxyethylene octylphenol ether (OP-10),4-octylphenol and octadecylamine were added into the condensation system, and different adding amounts were also investigated. The surface properties and demulsifying time of the new asphalt emulsifiers were tested. It drew a conclusion that the emulsifying properties of all these modified products increased. Among them, the octadecylamine modified products increased greatly, followed by the OP-10 modified products.Three asphalt emulsifiers with the best emulsifying properties in each type were used to emulsify the matrix asphalt. The appearance, size and contents of the evaporation residue were in accordance with common anionic emulsified asphalts. What's more, they had good flexibility with cement and high storage stability. The CA mortar, a blend of asphalt emulsion, cement and fine sand, could meet the main performance requirements, such as flowability, separating degree, volume-weight, compressive strength and elastic modulus.