Film reaction kinetics for melt postpolycondensation of poly(ethylene terephthalate)

Abstract

Melt polycondensation has recently been reported to prepare high‐viscosity poly(ethylene terephthalate) (PET), the reaction efficiency is greatly improved in over 10‐folds compared with conventional solid state polycondensation (SSP). Melt postpolycondensation of common PET chips was conducted in specified film thickness to obtain industrial PET. Based on the investigation of reaction conditions, film reaction kinetics were determined in the principle of end groups analysis. It was positively regulated that the intrinsic viscosity of PET could be achieved in condition of high vacuum, thin melt film and proper temperature, degradation reaction would be increased at exorbitant temperature. An apparent reaction kinetic model was proposed and was verified by experiments. Results indicated the activation energy of melt postpolycondensation of PET was 88.22 kJ/mol and the reaction rate constant was significant higher than that of solid state polycondensation.

Biodegradable High-Molecular-Weight Poly(pentylene adipate-co-terephthalate): Synthesis, Thermo-Mechanical Properties, Microstructures, and Biodegradation

“…Thin-layer films reduce the mass transfer path of the byproduct (1,5-pentanediol), allowing the polycondensation reaction to continue and increasing molecular weight. Previous studies on poly­(ethylene terephthalate) synthesis show that higher temperature, higher vacuum, and thinner films facilitated the diffusivity of byproducts in polymer melts . However, overly high temperatures (>240 °C) and long reaction times caused degradation of polypropylene terephthalate and polybutylene terephthalate and increased carboxyl groups. ,, Therefore, the effects of reaction temperatures on the polycondensation of PPAT were explored.…”

“…29 However, overly high temperatures (>240 °C) and long reaction times caused degradation of polypropylene terephthalate and polybutylene terephthalate and increased carboxyl groups. 29,30,26 Therefore, the effects of reaction temperatures on the polycondensation of PPAT were explored.…”

Comparison of Eco-friendly Ti–M Bimetallic Coordination Catalysts and Commercial Monometallic Sb- or Ti-Based Catalysts for the Synthesis of Poly(ethylene-co-isosorbide terephthalate)

“…Semicrystalline thermoplastic polyesters are in wide spread use in our daily life and engineering construction, ranging from bottles for carbonated soft drinks and water to fibers for apparels and string. − Although some polyesters, such as polytrimethylene terephthalate, polybutylene terephthalate (PBT), polyethylene naphthalate, and others, have been commercially successful, they cannot compete with polyethylene terephthalate (PET) in terms of cost-performance. PET has evolved into the most sought-after and most consumed material type in the fields of global textile, soft drink bottles, food packaging, and industrial fiber as a result of the simple availability of monomers and advanced production technology. , Synthetic bio-based polyesters have received a lot of attention in both research and application due to the limitation of petroleum resources.…”

Correlation between structural evolution and rheological properties for polycarbonate in the molten state

“…The property of PC is primarily determined by their molecular weight, 5 however, it is difficult to fabricate high molecular weight PC due to the technological limitations of the melt transesterification process 6,7 . Melt post‐polycondensation (MPP) process is one of the most common industrial techniques applied to produce high molecular weight polyesters, for example, poly(ethylene terephthalate) (PET) and PC 8,9 . Compared with solid‐state polycondensation (SSP), 10,11 the MPP process possesses a higher reaction efficiency, so it has been attracting more industrial interest due to the low consumption of time and energy 12,13 …”

“…6,7 Melt post-polycondensation (MPP) process is one of the most common industrial techniques applied to produce high molecular weight polyesters, for example, poly(ethylene terephthalate) (PET) and PC. 8,9 Compared with solid-state polycondensation (SSP), 10,11 the MPP process possesses a higher reaction efficiency, so it has been attracting more industrial interest due to the low consumption of time and energy. 12,13 However, the high temperature in the MPP process not only accelerates the progress of the polycondensation reaction but also easily gives rise to a series of side…”