Microfluidic Process Intensification for the Synthesis of Nitrogen-Containing Bio-Based Polyols via Aminolysis of Epoxidized Soybean Oil

A continuous-flow microfluidic strategy was developed for the synthesis of nitrogen-containing bio-based polyols via cyclohexylamine aminolysis of epoxidized soybean oil (ESO). The effects of temperature, residence time, catalyst loading, flow rate, and channel diameter on epoxy and hydroxyl values were systematically investigated. Under optimal conditions (100 °C, 60 min, 5 wt% catalyst), a hydroxyl value of 259 mgKOH/g and a residual epoxy value of 0.11% were achieved. Compared to a conventional batch process requiring 12 h, the microfluidic method shortened the reaction time to minutes while delivering significantly higher hydroxyl values and narrower molecular weight distribution. FTIR, GPC, DSC, and TGA analyses confirmed more complete conversion, suppressed etherification side reactions, and superior structural uniformity in the microreactor-derived products. Based on the experimental results, microfluidic processing showed the potential for efficient and sustainable production of nitrogen-containing bio-based polyols.