Poly lactic acid production using the ring opening polymerization (ROP) method using Lewis acid surfactant combined iron (Fe) catalyst (Fe(DS)3)

Abstract

LASC catalyst synthesis process was carried out using iron metal (Fe) and its characterization properties were tested. There are five stages carried out, namely, the manufacture of the LASC Fe(DS)3 catalyst, lactic acid dehydration, polycondensation of lactic acid into l-lactic acid oligomers (OLLA), depolymerization of oligomers into l-lactide, and the ROP process to convert l-lactide into Polymers. l-lactic acid (PLLA). The analysis used is as follows, Karl-Fisher; Spectroscopy Fourier Transform Infrared (FTIR); and Nuclear Magnetic Resonance (HNMR); Gel Permeation Chromatography (GPC); Thermogravimetry Gravity Analysis (TGA) and X-Ray Diffraction (XRD). Based on the experimental results, the catalyst Fe(DS)3 has a crystallinity value of 24% which indicates an amorphous nature and is easy to react. The value of the thermal stability of the catalyst is at 180 °C where the catalyst is able to process up to a temperature of 180 °C. Each step of the ROP is validated by FTIR analysis which shows that the components of the group are in accordance with the expected product. The comparison of the crystallinity values of PLA produced with FeCl3 and Fe(DS)3 were 37.5 and 49%, respectively. Melting temperature (Tm) values are 111 and 107 °C, respectively, Td values are 327 and 352 °C, and the resulting molecular weights are 23,720 and 20,232 g/mol. Based on the results obtained, it can be seen that the use of a LASC catalyst in the form of Fe(DS)3 is more effective than without using a LASC catalyst.