Design of sustainable polymers based on 2,5-furanodicarboxylic acid and evaluation of their (bio)degradability

• Autor(a) principal: Patrício, Rafael Marques
• Data de Publicação: 2021
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10773/31009
• topic: Poly (ethylene 2,5-furandicarboxylate); Copolyesters; Poly (isosorbide 2,5- furandicarboxylate)-co-poly(isosorbide 1,12 - dodecanedioate); (Bio)degradation; Penicillium brevicompactum

The excessive production of conventional polymers (routinely called plastics), and the related depletion of fossil sources, as well as the environmental pollution, has prompted massive research on sustainable polymers alternatives to current fossil-based homologs. 2,5-Furandicarboxylic acid (FDCA) has been highlighted as a promising bio-based key chemical for polyesters production, mainly due to the similarity of this renewable monomer with the well-known terephthalic acid (TPA). One of the most promising FDCA-based polyesters developed so far is, undoubtedly, poly(ethylene 2,5-furandicarboxylate) (PEF). PEF is considered the renewable alternative to the fossil-based poly(ethylene terephthalate) (PET), suitable for packaging applications, among others. PEF has a very interesting set of properties, including, for example, high thermal properties and superior barrier behavior. Despite the enormous efforts put in studying PEF properties and applications, PEF end-life has been barely addressed. In this vein, in this work, we aim to study the biodegradation of PEF using the Penicillium brevicompactum fungus (Chapter. II). The biodegradation of PEF by the fungus was evaluated through gravimetric and ATR-FTIR analyses. P. brevicompactum did not demonstrate the ability to degrade PEF. On the contrary, a negative effect was observed on the growth of the fungus. These results intensify the hypothesis that PEF is poorly biodegradable and highlight the need to better study alternative more biodegradable polymers. Therefore a series of copolyesters from the FDCA and other renewable-based aliphatic compounds the poly(isosorbide 2,5-furandicarboxylate)-copoly( isosorbide 1,12-dodecanedioate) (PIsFDD) were successfully synthesized. Their structure was checked by ATR-FTIR, 1H and 13C NMR, and X-ray diffraction, and their thermal properties were evaluated by TGA, DSC, and DMTA. The PIsFDD copolyesters depending on the monomeric quantities exhibited amorphous or semi-crystalline character and thermal stability up to 290 °C. Additionally, hydrolytic/enzymatic degradation of PIsFDDs showed promising results namely for PIsFDD 10/90 a 10.5% weight loss was reached. These copolyesters showed the potential to be applied as (bio)degradable products.