Dynamics of Formation of Asphalt Microstructure According to Modulated Differential Scanning Calorimetry Data

Resumo

The structural thermal properties of petroleum asphalts (using the BNK 40/180 brand as an example) have been analyzed by modulated differential scanning calorimetry (DSC). The method is based on separation of the overlapping reversing and nonreversing structural thermal processes upon temperature modulation of a heat flow, which makes it possible to observe, analyze, and quantitatively assess the thermal effects that are displayed on the temperature curves of conventional DSC. The method ensures the separation of crystallization (melting) processes and glass transitions. The temporal dynamics of the formation of asphalt microstructure is determined by rapid (shorter than 1 h), medium (up to 16 h), and slow (longer than 16 h) thermal processes of crystallization of paraffin hydrocarbons (HCs) of various structures and separation of asphaltenes into an individual nanosized phase.