Enzymatic Degradation of Poly(ethylene 2,5-furanoate) Powders and Amorphous Films

Abstract

Poly(ethylene 2,5-furanoate) (PEF) is arousing great interest as a biobased alternative to plastics like poly(ethylene terephthalate) (PET) due to its wide range of potential applications, such as food and beverage packaging, clothing, and in the car industry. In the present study, the hydrolysis of PEF powders of different molecular masses (M n = 55, M w = 104 kg/mol and M n = 18, M w = 29 kg/mol) and various particle sizes (180 < d and 180 < d < 425 µm) using cutinase 1 from Thermobifida cellulosilytica (Thc_cut1) was studied. Thereby, the effects of molecular mass, particle size and crystallinity on enzymatic hydrolysis were investigated. The results show that particles with lower molecular mass are hydrolyzed faster than those with higher masses, and that the higher the molecular mass, the lower the influence of the particle size on the hydrolysis. Furthermore, cutinases from Humicola insolens (HiC) and Thc_cut1 were compared with regard to their hydrolytic activity on amorphous PEF films (measured as release of 2,5-furandicarboxylic acid (FDCA) and weight loss) in different reaction media (1 M KPO pH 8, 0.1 M Tris-HCl pH 7) and at different temperatures (50 • C and 65 • C). A 100% hydrolysis of the PEF films was achieved after only 72 h of incubation with a HiC in 1 M KPO pH 8 at 65 • C. Moreover, the hydrolysis reaction was monitored by LC/TOF-MS analysis of the released reaction products and by Scanning Electron Microscopy (SEM) examination of the polymer surfaces. Enzymatic hydrolysis of PEF with Thc_cut1 and HiC has potential for use in surface functionalization and recycling purposes.

A Middle-Aged Enzyme Still in Its Prime: Recent Advances in the Field of Cutinases

“…This polymer exhibits improved mechanical and gas barrier properties in comparison to PET, and thus it has raised industrial interest. The depolymerization of PEF powders with different molecular masses, crystallinities, and particle sizes has been reported, using cutinase Thc_cut1 [112]. It was shown that amorphous particles of lower molecular mass are hydrolyzed faster and to a greater extent compared to high molecular weight and crystalline ones.…”

Broadband Dielectric Spectroscopy Study of Biobased Poly(alkylene 2,5-furanoate)s’ Molecular Dynamics

“…Such polyester represents indeed the most credible bio-based alternative to poly(ethylene terephthalate) (PET) because of its properties, which are even superior to those of its terephthalic counterpart. Notable are the very good mechanical and the excellent gas barrier properties, which render this new polymer a very promising candidate in the food and beverage packaging [6][7][8][9][10][11][12][13][14][15][16]. More recently, the attention of researchers has been addressed on other polyesters of the family, specifically those containing a longer glycol subunit with respect to PEF.…”

Tailoring Biodegradability of Poly(Butylene Succinate)/Poly(Lactic Acid) Blends With a Deep Eutectic Solvent

“…Concerning the environment, higher temperatures, if they do not kill microorganisms, often lead to faster degradation, and a degradation temperature close or higher than the glass transition temperature (T g ) favors the biodegradation process. Indeed, at temperatures above the T g of a polymer, increased chain mobility facilitates access to enzymes (Weinberger et al, 2017), as well as water absorption (Siparsky et al, 1997). This explains that, at temperatures under their T g , polyesters such as PLA are not likely to degrade, whereas they significantly age at temperatures close to their T g (Agarwal et al, 1998;Itävaara et al, 2002;Yagi et al, 2009;Karamanlioglu and Robson, 2013).…”