DEVELOPMENT OF RENEWABLE NON-ISOCYANATE POLYURETHANE FROM WASTE OIL-BASED POLYOLS: APPLICATION FOR POROUS MATERIAL
Polyurethane (PU) is widely employed in various applications, including foams, coatings, adhesives, and elastomers, due to its exceptional versatility, durability, and mechanical properties. However, conventional PU production primarily relies on isocyanates, which pose significant health risks and are derived from non-renewable fossil fuels, thereby contributing to environmental deterioration. Non-isocyanate polyurethane (NIPU) offers a safer and more sustainable alternative. The synthesis of NIPU eliminates the requirement for hazardous isocyanates, thus reducing health hazards and ecological impacts. Additionally, NIPU enables the use of renewable raw materials, such as polyols obtained from waste oils, thereby fostering a circular economy and decreasing reliance on fossil fuels.
Supported by the Mitacs Globalink Research Award, this project focused on the synthesis of polyurethane and the determination of iodine values of dehydrogenated oil, epoxidized oil and oil-based polyols extracted from waste oils through dehydrogenation, epoxidation, and hydroxylation techniques. Critical process parameters, including reaction time, temperature, and catalyst choice, were meticulously optimized to improve the formation of epoxide groups, which are essential for the subsequent polyol synthesis. The optimal conditions of the dehydrogenation process resulted in an average iodine value of 121 ± 2.15, an increase from 95.5 ± 0.57 in the initial iodine value of waste oil during the dehydrogenation phase, achieving a conversion efficiency of about 77% for the oil and an epoxide selectivity of 74.%. These results were achieved using a 3% Ni/TS-1 catalyst, a 1:5 oil-to-hydrogen peroxide ratio, and a reaction temperature maintained at 65°C for a duration of 3 hrs. The resultant epoxidized oil cloud has implications for polyols that demonstrate considerable promise for forthcoming NIPU synthesis, providing an eco-friendly alternative to conventional polyurethane production methods. By leveraging waste oil, this strategy mitigates industrial waste and carbon emissions, thus fostering a more sustainable framework for polymer manufacturing.