Degradation of biobased poly(ethylene 2,5‐furandicarboxylate) and polyglycolide acid blends under lipase conditions

Abstract

Bio-based polymer materials are considered to have function of protecting the environment, and improving the degradation performance of bio-based polymer materials is of great significance to realize the green cycle of production-use-degradation of plastic products. This present work is focused on the investigation of the degradation behavior of bio-based polymer blend poly(ethylene 2,5-furandicarboxylate) /polyglycolide acid (PEF/PGA) with different composition ratios in phosphate-buffered saline (PBS solution, pH = 7.4) with 0.5 mg/mL of lipase from porcine pancreas. The results observed that the thermal decomposition temperatures at 5% weight loss of both the PEF/PGA blends are higher than 310 C, which reflected that the PEF/PGA blends possessed excellent thermal stability. The water absorption of the PEF/PGA blends continued to increase with increasing the PGA content. This trend is consistent with the mass loss of blends in the degradation process. The systematic degradation study revealed that the neat PEF showed no mass loss in both PBS solution with and without lipase, while the PEF/PGA blends possessed a faster rate under enzymatic degradation circumstance in the first 4 weeks, and the weight loss in the same degradation period increase with increasing the PGA content due to the erosion of lipase on the polymer chain. In particular, the weight loss of PEFGA40 blend was more than 18.33% after 8 weeks of degradation in enzyme solution. 1 H NMR results showed that in addition to PGA component as a major component of degradation, a small amount of PEF component was also involved in the mass loss of the blend during degradation. At the same time, the short-chain segment produced during the degradation had a clear plasticizing effect on the PEFGA blends, which is reflected in that the T g of PEFGA40 blend decreased first and then increased with the increase of degradation time.

Simultaneous Thermodynamic Favorable Compatibility and Morphology to Achieve Balanced Physical Properties and Biodegradability in bio-PEF/PGA/PCL Blends

“…This indicates that the hydrophilicity and degradation rate of the structured mats were improved by increasing the PGA amount of electrospun nanofibers due to the fact that PGA has a much higher wettability than that of PCL, due to the multiple hydrophilic functional groups . In addition, it was also found in our previous study that, after PGA was introduced to the PEF matrix, the PEF/PGA blends exhibited obvious degradation behavior, and the mass loss rate of the blends increased with an increase of the PGA content because the high hydrophilicity of PGA accelerated the contact of PEF with enzymes and water . Despite this, the high crystallinity and high tensile strength of PGA cannot improve the flexibility of PEF.…”

“…In our previous study, we found that when PGA was introduced into the PEF matrix, significant mass loss of the PEF matrix occurred during the degradation process of the PEF/PGA blends within 8 weeks, indicating that the introduction of PGA components can indeed accelerate the degradation process of PEF. 24 Similarly, Guebitz et al found that the PEF homopolymer undergoes significant degradation behavior in the presence of cutinase. 51,52 Based on this, the degradation process of the PEF/PGACL blend was summarized in Figure 12G.…”

“…23 In addition, it was also found in our previous study that, after PGA was introduced to the PEF matrix, the PEF/PGA blends exhibited obvious degradation behavior, and the mass loss rate of the blends increased with an increase of the PGA content because the high hydrophilicity of PGA accelerated the contact of PEF with enzymes and water. 24 Despite this, the high crystallinity and high tensile strength of PGA cannot improve the flexibility of PEF. Therefore, in this paper, we also select PCL, another polymer with high toughness and degradable properties, by preblending it with PGA and then blending it with PEF for modification, in order to obtain a new composite material with good degradation performance and mechanical properties, especially toughness.…”

From green to circular chemistry paved by biocatalysis

“…120 In addition, the hydrolysis of bio-based polymer blends, such as poly(ethylene 2,5-furandicarboxylate)/polyglycolide acid, can be achieved using porcine pancreas lipase in aqueous saline media. 121 Polyurethane (PU) is another plastic product with huge environmental impact. PU is produced per year on a global scale at 23.89 million metric tons in 2022 and with an increasing rate of 5% per year.…”

“…120 In addition, the hydrolysis of bio-based polymer blends, such as poly(ethylene 2,5-furandicarboxylate)/polyglycolide acid, can be achieved using porcine pancreas lipase in aqueous saline media. 121…”