Purpose The purpose of the study is to synthesize the thio-containing furan-imine-diol monomer using biomass-based 5-Hydroxymethylfurfural (HMF) and thiosemicarbazide. Design/methodology/approach A biomass-based furan-imine diol was prepared by reacting 5-HMF and thiosemicarbazide in a 2:1 molar ratio. The structural modification of the prepared diol was confirmed by Fourier Transform Infrared (FT-IR), H1 nuclear magnetic resonance (1H NMR) and liquid chromatography–mass spectrometry (LC-MS) spectroscopic techniques. The resulting diol is then subjected to a reaction with various diisocyanates to yield a series of bio-based urethanes. The chemical modification of the prepared urethane was confirmed by FT-IR spectroscopy, the thermal behavior was studied using thermogravimetric analysis and differential scanning calorimetry. Furthermore, the crystallinity of urethanes was determined by X-ray diffraction (XRD) analysis. Findings The prepared urethanes were confirmed by FT-IR spectroscopy, which showed the complete disappearance of -NCO stretching and formation of urethanes. The thermal behavior of urethanes showed a three-stage degradation and exhibited good thermal stability. The XRD study represented the semi-crystalline behavior with diffraction peaks around 20° for all the urethanes. Research limitations/implications In this experimental task, molecular weight determination was not performed due to eluent limitation in gel permeation chromatography (GPC) as well as intrinsic viscosity measurements. Characterization like molecular weight and viscosity of polymer required for the certainlty of polymer formation. Originality/value This study utilizes a bio-based 5-HMF component and petrochemical-based thiosemicarbazide for developing thio-containing furan-imine-diol and its urethanes.
Borane et al. (2026) studied this question.