Articles

This study presents a comparative investigation of two common catalysts - p-toluene sulfonic acid (p-TSA, a strong organic Brønsted acid) and aluminum chloride (AlCl 3 , a Lewis acid) over non-catalyst one in the polycondensation of succinic acid (SA) with 1,3-propane diol (PDO) to form poly (trimethylene succinate) (PTSu). Reaction parameters (temperature, catalyst loading, and time) were systematically varied to evaluate catalyst efficiency with respect to (i) degree of polymerization, (ii) the rate of reaction of polycondensation, (iii) esterification rate, (iv) order of the reaction, and (v) activation energy of the reaction. Analytical techniques included FTIR & 1 H NMR. Mechanistic differences between Brønsted and Lewis acid catalysis are discussed. Results (representative data and trends are provided) indicate that p-TSA yields faster initial esterification and higher final molecular weights under identical conditions. In contrast, the AlCl 3 catalyst exhibits similar activity to the p-TSA catalyst. Among the non-catalyst, p-TSA, and AlCl 3 catalysts, the p-TSA and AlCl 3 catalysts performed well in the polycondensation reaction over the non-catalyst one.