Monitoring of lignin-based polyurethane synthesis by FTIR-ATR

FTIR (Fourier Transform Infrared Spectroscopy), working in ATR (Attenuated Total Reflectance) mode was applied to study the formation of lignin-based polyurethanes. Although some studies related to the use of lignins in polyurethane synthesis, are available in literature, still persist a gap for a systematic study of this kind of systems involving the measurement of kinetic data, optimization and modelling of the process. This methodology allows the test of different formulations at a scale of 3-5 grams, considering several process variables: temperature, NCO/OH ratio, type and MW of the polyol, type of isocyanate, type and weight content of lignin. This work aims to describe the methodology used to perform the FTIR experiments by presenting a case study