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This study describes the synthesis, the spectroscopic, and the thermal characterization of linear and crosslinked polymers as well as a number of corresponding model compounds, containing Diels–Alder adducts derived from furan and maleimide groups. The thermal reversibility (rDA, DA) of structurally varied model compounds, polymeric and network structures were studied by differential scanning calorimetry, where possible in combination with 1H NMR spectroscopy. It was established that the endo and exo DA stereoisomers show significantly different thermal responses: the rDA of the endo DA‐adducts typically takes place at 20–40 K lower temperatures than that of the corresponding exo DA‐adducts in all cases, with the exception of some aromatic maleimides. Although in situ isomerization was observed to a limited extent and only in some cases, this effect is not expected to influence the thermoremendability of DA‐crosslinked networks being dependent on two separate stereoisomeric rDA steps. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3456–3467, 2010

The production of drop‐in chemicals from bio‐based renewable sources is gaining a lot of momentum due to proven negative impact of fossil‐based economy on environment and society. In this Review, various bio‐derived platform molecules are assessed as renewable alternatives to fossil resources for the catalytic production of acrylates. Acrylic acid and its esters are key building blocks of a large number of high‐value oligomers and polymers in the current industry. In spite of the encouraging successes reported on gram or lab‐scale, real implementation of bio‐based examples remain scarce mainly due to the current high cost and limited availability of the bio‐based substrates. As lactic acid and their derivatives are one of the most promising feedstocks for bio‐acrylate production, they are the main focus of this Review.

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.

Methyl lactate (ML) conversion to methyl acrylate is studied in the gaseous phase over ZSM-5 zeolite catalysts. High acrylate selectivity and catalyst service time were achieved using the K-ZSM-5 catalyst with low content of Brønsted acid sites (below 1 μmol g −1 ) and an overall K-to-Al atom ratio of unity. Feeding of ML in methanol containing 5 to 25 vol % of water improves catalyst stability. As such, up to 80% acrylate yield at complete ML conversion, along with minor deactivation after days-on-stream and fully recoverable catalysis, is presented.

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A new silicon‐containing spiroorthoester, 1,4,6‐trioxaspiro [4,4]‐2‐nonylmethyl 3‐trimethylsilyl propionate (SOESi), was synthesized with good yield by an esterification reaction with a previously synthesized 2‐hydroxymethyl‐1,4,6‐trioxaspiro [4,4] nonane (SOEOH) and trimethylsilyl propionic acid. The structure of the new SOESi was confirmed by 1H and 3C NMR. The SOESi and a mixture of DGEBA/SOESi were polymerized with ytterbium triflate as a cationic initiator. The curing was studied with differential scanning calorimetry (DSC) and monitored by Fourier transform infrared (FTIR) spectroscopy. The materials were characterized with DSC, termogravimetric analysis (TGA) and thermodynamomechanical analysis (DMTA). The volume change was evaluated with a Micromeritics gas pycnometer and the flame retardancy was tested by the limiting oxygen index (LOI) measurements. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4211–4224, 2007

The cationic copolymerization of 2‐phenoxymethyl‐1,4,6‐trioxaspiro[4,4]nonane with DGEBA under microwave irradiation using ytterbium and lanthanum triflates as initiators is described. A comparison with thermal heating showed a great enhancement in the reaction rates and a higher SOE incorporation in the network. The double ring opening of SOE reduces the usual shrinkage of epoxy resins on curing, and it was lower under microwave irradiation. Moreover, the ytterbium triflate initiator lead to a higher incorporation of linear ester moieties in the network than lanthanum triflate.