Abstract
In this study, the synthesis of poly(ethylene furanoate) (PEF), catalyzed by five different catalysts—antimony acetate (III) (Sb Ac), zirconium (IV) isopropoxide isopropanal (Zr Is Ip), antimony (III) oxide (Sb Ox), zirconium (IV) 2,4-pentanedionate (Zr Pe) and germanium (IV) oxide (Ge Ox)—via an industrially common combination of melt polymerization and subsequent solid-state polymerization (SSP) is presented. In all reactions, proper amounts of 2,5-dimethylfuran-dicarboxylate (DMFD) and ethylene glycol (EG) in a molar ratio of DMFD/EG= 1/2 and 400 ppm of catalyst were used. Polyester samples were subjected to SSP procedure, under vacuum application, at different reaction times (1, 2, 3.5, and 5 h) and temperatures of 190, 200, and 205 °C. Carboxyl end-groups concentration (–COOH), intrinsic viscosity (IV), and thermal properties, via differential scanning calorimetry (DSC), were measured for all resultant polymers to study the effect of the used catalysts on the molecular weight increase of PEF during SSP process. As was expected, it was found that with increasing the SSP time and temperature, the intrinsic viscosity and the average molecular weight of PEF steadily increased. In contrast, the number of carboxyl end-groups content showed the opposite trend as intrinsic viscosity, that is, gradually decreasing during SSP time and temperature increase. It is worthy to note that thanks to the SSP process an obvious and continuous enhancement in the thermal properties of the prepared PEF samples was attained, in which their melting temperatures (Tm) and degree of crystallinity (Xc) increase progressively with increasing of reaction time and temperature. To predict the time evolution of polymers IV, as well as the hydroxyl and carboxyl content of PEF polyesters during the SSP, a simple kinetic model was developed. From both the theoretical simulation results and the experimental measurements, it was demonstrated that surely the Zr Is Ip catalyst shows the best catalytic characteristics compared to all other used catalysts herein, that is, leading in reducing—in a spectacular way—the activation energy of the involved both transesterification and esterification reactions during SSP.
Highlights
In recent years, the interest to develop biobased ecofriendly polymeric materials derived from biomass—instead of petroleum-based polymers—has emerged with renewed strength
As one of very limited studies reporting the effect of the catalyst type on molecular weight increase of poly(ethylene furanoate) using solid-state polymerization, the aim of this work was to study the feasibility of poly(ethylene furan dicarboxylate) (PEF) SSP, using a series of catalysts—Antimony Acetate (III) (Sb Ac), Zirconium (IV)
Solid-state polymerization of the ecofriendly polyester PEF was investigated with a variety of catalysts at several temperatures
Summary
The interest to develop biobased ecofriendly polymeric materials derived from biomass—instead of petroleum-based polymers—has emerged with renewed strength. The USA and European legislative landscapes are changing in favor of renewable resource-based products against fossil-based ones [8,9] In this context, and thanks to the rapid development of the chemical industry and the optimization of biorefining processes [10,11], large-scale production of renewable resource-derived monomers has been developed in the last few years and are widely used as starting building blocks for biobased polymers production [12–14]. For the above-mentioned reasons, a paradigm shift has emerged towards synthesizing of different homopolymers derived from the renewable-based aromatic diacid monomer (FDCA) and several diols [17–27] In this sense, FDCA is on the way of industrialization and commercialization by many international companies, including Corbion, Avantium, ADM, BASF, and DuPont [28]. As a relevant example of sustainable FDCA-based polymers from renewable resources, poly(ethylene furan dicarboxylate) (PEF), produced from either
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.