Multiscale Computational\nStudy of Cellulose Acetate–Water\nMiscibility: Insights from Molecularly Informed Field-Theoretic Modeling

Cellulose acetate (CA), a prominent water-soluble derivative\nof\ncellulose, is a promising biodegradable ingredient that has applications\nin films, membranes, fibers, drug delivery, and more. In this work,\nwe present a molecularly informed field-theoretic model for CA to\nexplore its phase behavior in aqueous solutions. By integrating atomistic\ndetails into large-scale field-theoretic simulations via the relative\nentropy coarse-graining framework, our approach enables efficient\ncalculations of CA’s miscibility window as a function of the\ndegree of substitution (DS) of cellulose hydroxyl groups with acetate\nside chains. This allows us to capture the intricate phase behavior\nof CA, particularly its unique miscibility at intermediate substitution,\nwithout relying on experimental input. Additionally, the model directly\nprobes CA solution behavior specific to the relative DS at C2, C3,\nand C6 alcohol sites, providing insights for the rational design of\nwater-soluble CA for diverse applications. This work demonstrates\na promising integration of molecularly informed field theories, complementing\nwet-lab experimentation, for engineering the next-generation polymeric\nmaterials with precisely tailored properties.