Liquefaction of Ruscus aculeatus Branches into Bio-Polyols: Process Optimization and Polyol Characterization

The conversion of lignocellulosic biomass into bio-polyols through liquefaction has attracted increasing interest as a sustainable route for polymer feedstock production. The liquefaction of Ruscus aculeatus L. branches was investigated to identify optimal processing conditions and to evaluate the properties of the resulting bio-polyols. The effects of temperature, reaction time, particle size, and material-to-solvent ratio on liquefaction yield were systematically studied. Liquefaction yield increased markedly with temperature, reaching up to 92% at 180 °C after 60 min of reaction, while reaction time showed only a marginal effect beyond 15 min. Smaller particle sizes and higher solvent ratios improved liquefaction efficiency, with optimal conditions identified between 1:7 and 1:10 material-to-solvent ratios. The hydroxyl number decreases with increasing liquefaction temperature due to dehydration and condensation reactions. Thermal and rheological analyses indicated improved thermal stability and increased viscosity at higher liquefaction temperatures. These results highlight the potential of Ruscus aculeatus branches as a promising renewable feedstock for bio-polyol production and polyurethane applications.