Commercial sunflower oil was epoxidized at the laboratory-scale. The
epoxidized sunflower oil (ESFO) was modified following the acrylation reaction.
Modification was carried out simultaneously using acrylic acid (AA) and
triethylamine (TEA). To optimize the reaction conditions, the effects of four
temperatures (40, 60, 80, and 100 °C), the ESFO:AA (100:100) ratio, and 0.2% TEA
were investigated. The rate of conversion was analyzed with both FT-IR and titration
of the oxirane ring. After that, the temperature with the highest conversion was
selected and used throughout for all modification reactions. Then, four ratios
(100:100, 100:90, 100:80, and 100:75) of ESFO:AA were analyzed at four different
concentrations of TEA (0.2, 0.3, 0.4, and 0.5%) to determine the best estimate for
both the ESFO:AA ratio and the catalyst concentration. Conversion rate was analyzed
using FT-IR spectroscopy by measuring the concentrations of ester, carbonyl, and
alcohol groups. Moreover, oxirane-ring concentration was estimated using the
titration method (with gentian violet as indicator) and FT-IR spectroscopy (epoxy
ring absorptions at 1270 cm<sup>−1</sup> and 877 cm<sup>−1</sup>). Based on
conversion yield, the optimum ESFO:AA ratio corresponds to 100:80; the best
temperature reaction was at 60 °C, and the best TEA concentration was 0.2%. The
critical amounts of reactants needed to reach maximum conversion were established.
The final acid value of the acrylated ESFO after washing (pH = 7) was 2.1 mg
potassium hydroxide (KOH)·g<sup>−1</sup>. All results show that FT-IR spectroscopy
is a simple, low-cost, rapid method for investigating the kinetics of a
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