Sodium Benzenesulfonate-Assisted Preparation of Lignosulfonate-Based Spherical Micelles: Insights from Mesoscopic Simulations

Sodium lignosulfonate (SL) has great potential to access lignosulfonate-based functional materials with high value. In this work, experiments and dissipative particle dynamics (DPD) simulations were employed to investigate the effect of sodium benzenesulfonate (SBS) on the preparation of lignosulfonate-based spherical micelles. DPD simulations and scanning transmission electron microscopy (STEM) analysis showed that independent sodium lignosulfonate (SL) molecules with various molecular weights only led to the formation of irregular and unordered aggregates in ethanol. Moreover, irregular and unordered SL aggregates with larger sizes were also obtained with increasing the molecular weight of SL. DPD simulations indicated that SL molecules with different molecular weights were able to self-assemble into various regularly spherical micelles in the presence of SBS, sodium p-methylbenzene benzenesulfonate, or sodium p-ethylbenzene benzenesulfonate. The SBS-assisted formation of lignosulfonate-based spherical micelles was attributed to the native formation of the SBS spherical base, and less than 10% of water was more beneficial to prepare the spherical micelles. STEM and cryo-scanning electron microscopy (cryo-SEM) analyses demonstrated that the SBS-assisted preparation of lignosulfonate-based spherical micelles with regular and ordered structures could be achieved using experimental methods.