Preparation And Performance Of Expoxy Asphalt

Epoxy asphalt, a special modified asphalt, is one of the senior paving materials used in Orthotropic Steel Bridge and heavy traffic roads. Since USA Epoxy Asphalt introduced to our country in 2000 and performing well in Long-span Bridge deck pavement, our country starts to focus on the development of domestic epoxy asphalt. In this paper, mechanical properties, curing process and modification mechanism of homemade epoxy asphalt were researched with the achievements shown following:(1) In research of mechanical properties, a formula of epoxy was found by tensile experiment that containing 100 phr epoxy resin,5 phr neopentyl glycol diglycidyl ethe,350 phr AH-70 asphalt, 10phr fatty acid anhydride and 85phr long chain aliphatic polyanhydride. The epoxy asphalt had great mechanical properties that tensile strength and elongation were 1.53MPa and 214%, respectively. The homemade epoxy asphalt also has good resistance to hot and humid environment(2) In research of curing process, analysis of initial curing rate, p post curing rate, infrared spectra and fluorescence was done to evaluate the epoxy asphalt The result of infrared showed that the curing process of epoxy asphalt material was accompanied by a change of epoxy groups, ester C=O=C and hydroxyl which conversely indicated the degree of curing process. It was also proved that the beginning of epoxy asphalt curing reaction was the eaction of carboxylic acid with epoxy but that of anhydride. The result of fluorescence analysis indicated the segregation of asphalt dispersion from mixture of epoxy resin and asphalt during curing process. Asphalt as the disperation will separate from the system to become a larger and larger grain.(3) In research of the modification mechanism, analysis of fluorescence, SEM, TG and DMA of homemade epoxy asphalt was done to evaluate the compatibility, microstructure and thermal stability. The fluorescence analysis showed that epoxy asphalt prepared with long chain fatty acid as curing agent had a good compatibility. TG analysis showed that decompose temperature did not change with the content of asphalt and ratio of curing agent while the content of unstable components in the materials increased with the content of asphalt. DMA analysis indicated that excellent product with high storage modulus would been obtained with appropriate content of asphalt inside, which would not chang the resistance of materials with the same Tg. When the ration of long chain aliphatic anhydride and fatty acid anhydride decreased, Tg of the product became higer which indicated the improvement of temperature resistance. At the same time, excellent product with high storage modulus would been found when the ration of long chain aliphatic anhydride and fatty acid anhydride is appropriate.