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沥青的氧化老化是铺筑物中沥青变硬的主要原因,进而促成各种形式的铺筑物开裂。在使用温度下氧化生成的可鉴别的主要官能团是酮和亚砜。在较高程度的氧化时生成数量明显的酸酐,显然不是经由羧酸而是从生成酮的同一种前驱体在特殊的芳香桥端位置上生成的。只有少量的羧酸生成。生成的亚砜受热则会分解,这样它们达到一个“稳态”浓度,而这个“稳态”浓度是一个温度和氧扩散速度的函数。已开发出微分红外技术定量地测定在氧化时已有的和/或生成的
Oxidation and aging of asphalt is the main reason that the asphalt in the pavement is hardened, which in turn leads to the cracking of various forms of paving. Identifiable major functional groups that are oxidatively generated at use temperature are ketones and sulfoxides. A significant amount of anhydride is formed upon a higher degree of oxidation, apparently not via carboxylic acids but from the same precursor of the ketone at a particular aromatic bridge end position. Only a small amount of carboxylic acid generated. The resulting sulfoxides will decompose when heated, so that they reach a “steady state” concentration, which is a function of temperature and oxygen diffusion rate. Differential infrared techniques have been developed to quantitatively determine what has been and / or is produced during oxidation