Synthesis of Bio-based Polyol Via Epoxidation and Hydroxylation of Shea Butter Fats

Abstract

Polyols are mostly made from petroleum and other non-biodegradable fossil fuels, and as such, they are not environmentally benign. This study presents the process of making bio-based polyols from shea butter fats (SBF) by epoxidation and hydroxylation. Wet analysis, gas chromatography with flame-ionization detection (GC-FID), and Fourier transform infrared spectroscopy (FTIR) were all used to characterize the bio-based polyols. The acid number (13.92 mg KOH/g), iodine value (19.54 mg I2/100 g), saponification value (218.03 mg KOH/g), and viscosity (107.98 poise) suggest a good quality of synthesized SBF-polyol. The FTIR analysis of SBF-polyol indicates the existence of specific vibrational frequencies: 3473 cm-1 for hydroxyl (OH) groups, 2921–2854 cm-1, and 2929–2858 cm-1 for carbon-hydrogen (C-H) and methylene (CH2) groups, respectively, and 1748 cm-1 for carbonyl (-C=O) groups. The major unsaturated fatty acids detected in SBF were oleic acid, with an estimation of 10.41%; linoleic acid and linolenic acid were reported at 0.34% and 1.67%, respectively; however, they were absent in SBF-polyol. According to this data, bio-based polyols can be synthesized using SBF and are suggested for the production of top-notch polyols.