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The Oseberg Viking ship burial is one of the most extensive collections of Viking wooden artefacts ever excavated in Norway. In the early twentieth century, many of these artefacts were treated with alum in order to preserve them, inadvertently leading to their current degraded state. It is therefore crucial to develop new bioinspired polymers which could be used to conserve these artefacts and prevent further disintegration. Two hydroxylated polymers were synthesised (TPA6 and TPA7), using α-pinene- and oleic acid-derived monomers functionalised with an acrylate moiety. Characterisation using biomolecular hydrodynamics (analytical ultracentrifugation and high precision viscometry) has shown that these polymers have properties which would potentially make them good wood consolidants. Conformation analyses with the viscosity increment (ν) universal hydrodynamic parameter and ELLIPS1 software showed that both polymers had extended conformations, facilitating in situ networking when applied to wood. SEDFIT-MSTAR analyses of sedimentation equilibrium data indicates a weight average molar mass Mw of (3.9 ± 0.8) kDa and (4.2 ± 0.2) kDa for TPA6 and TPA7 respectively. Analyses with SEDFIT (sedimentation velocity) and MultiSig however revealed that TPA7 had a much greater homogeneity and a lower proportion of aggregation. These studies suggest that both these polymers—particularly TPA7—have characteristics suitable for wood consolidation, such as an optimal molar mass, conformation and a hydroxylated nature, making them interesting leads for further research. [ABSTRACT FROM AUTHOR]

Ethanol is the main biofuel produced by fermentation route and the search for new feedstocks to produce fuel ethanol is still a great challenge. This work aims to compare the ethanol production from a new irrigated rice cultivar BRS AG to the conventional cultivar BRS PAMPA applied in Brazil. Six different commercial strains of Saccharomyces cerevisiae (BG-1, CAT-1, FT-858, JP-1, PE-2, and SA-1) were applied in fermentation reactions. Fermentations performed with BRS PAMPA rice revealed that the highest yields were achieved with strain SA-1, corresponding to 93.0% of the theoretical maximum and final ethanol concentration of 58.92 g L−1, and with CAT-1, a yield of 92.7% and final ethanol concentration of 58.93 g L−1. For the fermentations with BRS AG rice, the highest yields were obtained with strain FT-858, exhibiting a 89.6% yield and final ethanol concentration of 62.45 g L−1, and with CAT-1, 87.9% yield and final ethanol concentration of 61.25 g L−1 were achieved. The most appropriate microorganism for ethanol production using BRS PAMPA rice and BRS AG rice was CAT-1. Comparatively, the ethanol yield and productivity using BRS AG were higher than those observed for BRS PAMPA for all strains, except for PE-2 and SA-1 that led to very similar results. The experimental results showed that the giant rice BRS AG is an excellent feedstock for fuel ethanol production in lowland fields. [ABSTRACT FROM AUTHOR]

Polycaprolactone is a biodegradable, biocompatible, and versatile polymer commonly used in the pharmaceutical and biomedical industry and the development of new catalysts that allow for the synthesis under milder reaction conditions and in shorter reaction times is an appealing alternative. The iron-containing imidazolium-based ionic liquid 1-n-butyl-3-methylimidazolium heptachlorodiferrate was able to efficiently catalyze the ring-opening polymerization of ε-caprolactone under mild reaction conditions. Polymerization yields higher than 80% were obtained after 4 h of reaction at temperatures up to 85 °C, using low ionic liquid:ε-caprolactone molar ratios (1:720 − 1:1500), in the absence of solvent and without an intentionally added alcohol as an initiator. Semi-crystalline polycaprolactones, with molecular weights up to 14 kDa and narrow molecular weight distributions were synthesized. The chemical structure of the polymer was confirmed by Nuclear Magnetic Resonance (1H NMR) and Fourier Transform Infrared (FTIR) spectroscopy, and its crystalline content was estimated from the enthalpy of melting of the differential scanning calorimetry (DSC) thermogram. Finally, a caprolactone-activated ROP mechanism mediated by the ionic liquid was suggested. [ABSTRACT FROM AUTHOR]

The development of more sustainable materials from renewable resources has increasingly gained attention. In this work, commercial limonene oxide was used as a monomer to obtain polyesters with phthalic and maleic anhydrides. The ionic liquid 1-n-butyl-3-methylimidazolium heptachlorodiferrate (BMI·Fe2Cl7) was the catalyst for ring-opening polymerization. For both cyclic anhydrides, conversions around 80% were reached with a 1:100 catalyst:limonene oxide molar ratio. The resulting polymers presented a perfectly alternating structure, number-average molar mass over 1000 g mol−1, and pendant double-bonds that allow subsequent modification of their structures. Regarding their application, such as nanodevices for biological systems, poly(phthalic anhydride-co-limonene oxide) (PPALO) nanoparticles (NPs) were also produced and cross-linked with tetrathiol via thiol-ene reaction. The cross-linked PPALO-NPs with a number-weighted mean diameter of 56 nm, spherical morphology, and good colloidal stability were obtained. These NPs were tested for blood compatibility with human red blood (erythrocytes) cells and cell viability using mouse embryo fibroblast (NIH3T3) cell line, presenting potential for biomedical applications. [ABSTRACT FROM AUTHOR]

Molecularly imprinted polymers (MIP) are known as high selective sorbent, however, its application in aqueous medium is very limiting. In this way, a new hybrid MIP was successfully synthesized for saccharin (SAC) extraction in aqueous medium. SAC determination in surface waters becomes a challenge due to high dissipation that results in low concentration and susceptibility to potential interferences. Two polymer materials synthesized through bulk (HMIP-B) and suspension (HMIP-S) polymerizations were studied, and its performance has been compared according to morphological, adsorption isotherms, thermodynamics, and selectivity properties. The adsorption process was thermodynamically favorable and adsorption capacities (qe) were 1.24 and 4.32 mg g-1 for HMIP-B and HMIP-S, respectively. The material was characterized as heterogeneous with two binding sites fitted by Langmuir–Freundlich model and pseudo-second-order model. The imprinting factor (IF) was 4.8 for both materials and the HMIP-S presented superior results in selectivity, with a distribution constant (Kd) value of 12.1 times higher than HMIP-B for saccharin and a selectivity coefficient (k) of 7.73, 9.25 and 2.54 for acesulfame, caffeine and cyclamate, respectively. The selecitivity of HMIP in aqueous medium was tested in surface water samples, resulting in 89% of SAC recovery. [ABSTRACT FROM AUTHOR]