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为探讨沥青化学组成对其蜂状结构的影响,针对3种常用直馏沥青,考虑沥青中普遍存在的长链烷烃类、硫化物、稠环芳烃及沥青质类化合物的分布特性,进行了沥青微观相态组成成因的分子动力学模拟及试验研究。借助已知代表性化合物组装沥青分子模型,通过沥青元素组成、四组分分布、平均分子量及原子力显微镜形貌观测验证沥青分子模型的有效性。利用分子模型原子体积与表面特性势能场分布图及分子动力学轨迹图研究了不同分子对沥青微观相态组成的贡献。结果表明:沥青质是形成蜂状结构中高度较高的白色区的原因之一;长的烷基侧链尾部穿插在沥青质分子层间或大沥青质分子卷曲空白处,形成蜂状沉陷区;而极性大且空间位阻小的硫化物和稠环芳烃吸附在沥青质芳香环微区形成黏附力大但弹性模量低的沉陷区。
In order to investigate the influence of asphalt chemical composition on the bee structure, considering the distribution characteristics of long-chain alkanes, sulfides, polycyclic aromatics and asphaltene compounds prevailing in asphalt, Molecular dynamics simulation and experimental study on the causes of microscopic phase composition. The asphalt molecular model was assembled by known representative compounds. The asphalt molecular model was validated by the elemental composition of bitumen, the distribution of four components, the average molecular weight and the observation of atomic force microscopy. The contribution of different molecules to the microscopic phase composition of asphalts was investigated by using the potential energy field distribution and the molecular dynamics trajectory of molecular models of atomic volume and surface properties. The results show that asphaltenes are one of the reasons for the formation of highly white areas in the honeycomb structure. The long tail of alkyl side chains interspersed either in the asphaltene layer or in the curly space of large asphaltene molecules to form the bee-like subsidence area While the sulfides and condensed aromatic hydrocarbons with large polarities and small steric hindrance are adsorbed in the asphaltene aromatic ring micro-zone to form the subsidence zone with high adhesion and low elastic modulus.