RAFT Polymerization of Oleic Acid Based on Palm Oil: Effect of Temperature, Reaction Time, and Reactant Composition on the Characteristics of Oleic Acid Oligomers Using BBD-RSM

Abstract

This study aimed to investigate the effect of reaction temperature, reaction time, and reactant composition using 4-Cyano-(dodecylsulfanylthiocarbonyl)sulfanylpentanoic acid as a RAFT agent (CTA) and azobisisobutyronitrile (AIBN) as an initiator, on oleic acid oligomers derived from palm oil. Experimental variations were carried out within a reaction temperature range of 60°C–80°C, a reaction time of 24–48 h, and varying the ratio of oleic acid and chain transfer agent ([M]/[CTA] from 50 to 200. The interactions between variables were observed using RSM with Box–Behnken model, encompassing 16 experimental runs. The main responses evaluated included the number-average molecular weight (M_n) and degree of polymerization (DP). The results showed that the highest molecular weight and degree of polymerization values were 847 g mol⁻¹ and 3, respectively, with the resulting monomer conversion ranging from 55.51% to 81.67%. Notably, the smallest critical micelle concentration observed was 0.0807 mg mL⁻¹. Furthermore, the interaction between two variables (temperature–time and time-reactant ratio) also has a linear relation to molecular weight and degree of polymerization, with reaction temperature identified as the most significant influencing factor. The coefficient of determination (R²) of this model was 0.9795 with a p of 0.0002. Structural characterization by FTIR, ¹H-NMR, and ¹³C-NMR.