Kinetics study of the fully bio-based poly(propylene succinate) synthesis. Functional group approach

Currently, the increasing importance of the bio-based chemical compounds development is visible in the polymer chemistry, chemical engineering and materials science. It is well-known that the various purity level and different contaminants characterize petrochemical-based compounds compared to their bio-based counterparts. Therefore, it is necessary to find out the contaminants impact on the bio-based monomers synthesis. One of the most important information about the reaction pathway gave the kinetics study. In this work, the fully bio-based poly (propylene succinate)s were synthesized under various temperature conditions via two-step polycondensation reaction. The kinetics studies were investigated with the use of a functional group approach. The first step of the polycondensation reaction was autocatalytic esterification reaction. During the second step, the polycondensation catalyst was used. For macromolecular structure characteristics and the progress of the chemical reaction monitoring, Fourier Transform Infrared Spectroscopy, Proton Nuclear Magnetic Resonance, and Gel Permeation Chromatography were conducted. The activation energy value of 38.5 kJ/mol was determined for the first step of the bio-based polyols synthesis. The results of the investigations verified that the activation energy for the bio-based poly (propylene succinate) synthesis revealed lower value than the same polyester synthesis based on the petrochemical monomers. Thermal analysis by TGA measurements allowed confirmed the high thermal stability of the prepared bio-based polyols equaled ca. 418 °C.