反相气液色谱法研究沥青的吸氧老化性能

Investigation on the Ageing Characteristics of Asphalt on Absorption of Oxygen by Inverse Gas Liquid Chromatography

采用反相气液色谱技术,用甲苯将沥青溶解后均匀涂渍在担体上,作为固定相,在色谱吸氧老化条件下研究了沥青的吸氧老化性能。结果表明,沥青吸氧后相对极性增加,与沥青极性基团相似的分析物质的保留系数增加。氧化中各种沥青的老化综合指标存在较大的差别,可用来评价沥青的抗老化性能。

The ageing characteristics on oxygen absorption of asphalts have been studied at 140℃ and an oxygen flow rate of 15—30ml/min by inverse gas liquid chromatography. The asphalt was evenly coated on the inert support after dissolved in toluene and packed into the chromatographic column. The experimental results showed that the relative polarity of asphalt and the retention coefficients of analytical compounds having similar polar groups increased after absorbing oxygen. The changes in the retention coefficients of the oxygen-cotaining analysis compounds were evidently greater than that of the nitrogen and sulfur-containing and aromatic analysis compounds. The significant difference in the comprehensive index of ageing could be used to evaluate the antiageing performance of asphalt.