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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.

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Three novel phosphonated methacrylate monomers have been synthesized and studied for use in dental applications. Two of the monomers were synthesized from the reactions of glycidyl methacrylate (GMA) with (diethoxy‐phosphoryl)‐acetic acid (monomer 1) and (2‐hydroxy‐ethyl)‐phosphonic acid dimethyl ester (monomer 2). These monomers showed high crosslinking tendencies during thermal bulk and solution polymerizations. The third monomer (monomer 3) was prepared by the reaction of bisphenol A diglycidylether (DER) with (diethoxy‐phosphoryl)‐acetic acid and subsequent conversion of the resulting diol to the methacrylate with methacryloyl chloride. The homopolymerization and copolymerization behaviors of the synthesized monomers were also investigated with glycerol dimethacrylate (GDMA), triethylene glycol dimethacrylate (TEGDMA), and 2,2‐bis[4‐(2‐hydroxy‐3‐methacryloyloxy propyloxy) phenyl] propane (bis‐GMA) using photodifferential scanning calorimetry at 40 °C using 2,2′‐dimethoxy‐2‐phenyl acetophenone (DMPA) as photoinitiator. Monomer 1 showed polymerization rate similar or greater than dimethacrylates studied here but with higher conversion. The maximum rate of polymerizations decreased in the following order: 1∼TEGDMA>GDMA∼bis‐GMA∼3>2. A synergistic effect in the rate of polymerization was observed during copolymerizations. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2290–2299, 2008

In an effort to study the effect of substituent groups of the substrate on the alcohol dehydrogenase (ADH) reductions of aryl-alkyl ketones, several derivatives of acetophenone have been evaluated against ADHs from Lactobacillus brevis (LB) and Thermoanaerobacter sp. (T). Interestingly, ketones with non-demanding (neutral) para-substituents were reduced to secondary alcohols by these enzymes in enantiomerically pure form whereas those with demanding (ionizable) substituents could not be reduced. The effect of substrate size, their solubility in the reaction medium, electron donating and withdrawing properties of the ligand and also the electronic charge density distribution on the substrate molecules have been studied and discussed in detail. From the results, it is observed that the electronic charge distribution in the substrate molecules is influencing the orientation of the substrate in the active site of the enzyme and hence the ability to reduce the substrate.