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The current work was developed focusing on the synthesis of new polymeric latexes through the in reactor oxidative polymerisation of chia oil alkyd resins using the miniemulsion process. These latexes have potential applications, primarily in coating applications. Initially, an oil length mixture was obtained from chia oil through saponification and acidification reactions. The resulting mixture was characterized by 1H-NMR and 13C-NMR, confirming the presence of unsaturation and the characteristic functional groups associated with this compound. Phthalic anhydride and glycerol (esterification reaction) were used in the synthesis of alkyd resin. Alkyd resins were obtained by varying the oil length content in its composition: 30% wt% oil length alkyd resin is called short alkyd resin, 43% wt% oil length is medium resin and 64% wt% is the long alkyd resin. The 1H NMR spectra of alkyd resins showed peaks indicative of the presence of groups coming from phthalic anhydride and glycerol, as well as unsaturations that varied in intensity according to the size of the resin (short, medium or long). The miniemulsions were obtained from alkyd resins demonstrating colloidal stability over 90 days and with stable miniemulsions the oxidative polymerisation of the alkyd resins was carried out in a high-pressure reactor with temperature and pressure control and in the presence of the radicalinitiator benzoyl peroxide (BPO) and oxygen. Based on 1H-NMR analysis, polymers are formed through the oxidative polymerisation of alkyd resins from chia oil using the miniemulsion process. These polymers can be used as a paint base with a low solvent fraction or no solvent, depending on the application, and without using heavy metals-based catalysts. [ABSTRACT FROM AUTHOR]

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]

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]

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]

Glycerol is one of the major residues obtained during biodiesel transesterification. Microfibrillated cellulose was obtained from the empty bunches of palm oil, which is a residue of biomass extracted oil. Therefore, the objective of this work is to apply two important residues of oil chemistry industry, glycerol and lignocellulose biomass, in addition to acrylic acid to synthesize a polymer matrix in form of hydrogel for water absorption applications. To produce the polymer matrix, glycerol was modified with acrylic acid to obtain n-acylglycerol macromonomer with different reactive groups. The solution polymerizations were carried out between n-acylglycerol macromonomer, acrylic acid and bis-acrylamide in presence of microfibrillated cellulose (obtained from empty bunches of palm oil) to obtain hydrogels. The final material presented a high capacity of swelling water. The best material considering the swelling water contained 25 wt% of acrylic acid and 5 wt% of cellulose microfiber and absorbed 1400% of its own weight when produced in the optimized condition. [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]

Main conclusion: We report a soybean gene co-expression network built with data from 1284 RNA-Seq experiments, which was used to identify important regulators, modules and to elucidate the fates of gene duplicates. Soybean (Glycine max (L.) Merr.) is one of the most important crops worldwide, constituting a major source of protein and edible oil. Gene co-expression networks (GCN) have been extensively used to study transcriptional regulation and evolution of genes and genomes. Here, we report a soybean GCN using 1284 publicly available RNA-Seq samples from 15 distinct tissues. We found modules that are differentially regulated in specific tissues, comprising processes such as photosynthesis, gluconeogenesis, lignin metabolism, and response to biotic stress. We identified transcription factors among intramodular hubs, which probably integrate different pathways and shape the transcriptional landscape in different conditions. The top hubs for each module tend to encode proteins with critical roles, such as succinate dehydrogenase and RNA polymerase subunits. Importantly, gene essentiality was strongly correlated with degree centrality and essential hubs were enriched in genes involved in nucleic acids metabolism and regulation of cell replication. Using a guilt-by-association approach, we predicted functions for 93 of 106 hubs without functional description in soybean. Most of the duplicated genes had different transcriptional profiles, supporting their functional divergence, although paralogs originating from whole-genome duplications (WGD) are more often preserved in the same module than those from other mechanisms. Together, our results highlight the importance of GCN analysis in unraveling key functional aspects of the soybean genome, in particular those associated with hub genes and WGD events. [ABSTRACT FROM AUTHOR]

A modified sequential mass-suspension polymerization was employed to ensure adequate dispersion of lignin into the monomeric phase. Due to its complex macromolecular structure and low compatibility with styrene, eucalyptus wood-extracted lignin, via a modified Kraft method, was esterified with methacrylic anhydride to ensure organic phase homogeneity into the reaction medium. Infrared spectroscopy showed a decrease in the hydroxyl band, a characteristic of natural lignin (3200-3400 cm−1) and an increase in the characteristic ester band (1720-1740 cm−1) whereas nuclear magnetic resonance measurements exhibited intense peaks in the range from 1.7 to 2.05 ppm (-CH3) and 5.4 to 6.2 ppm (=CH2), related to methacrylic anhydride. Comparatively, the esterified lignin also displayed an increase of its glass transition temperature for 98 °C, related to natural lignin, whose Tg was determined to be equal to 91 °C. Styrene/lignin-based polymers exhibited higher average molar masses in comparison to the values observed for polystyrene synthesized with similar amounts of benzoyl peroxide, due to the ability of lignin to act as a free-radical scavenger. Composites obtained with styrene and natural or esterified lignin were successfully synthesized, presenting regular morphology and proper lignin dispersion. Based on a very simple polymerization system, it is possible to enhance the final properties of polystyrene through the incorporation of lignin, which represents an important platform for developing attractive polymeric materials from renewable resources. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the liveweight gain of lambs, infected by multidrug-resistant nematodes, treated by conventional schemes of helminth control or using a schedule based on fecal egg count reduction test (FECRT). The flock was selected after a FECRT (experiment 1) which revealed a parasite population resistant to benzimidazoles, imidazothiazoles, macrocyclic lactones (ivermectin), salicylanilides, nitrophenols, and organophosphates. Despite the parasite resistance to ivermectin (an avermectin), the moxidectin (a milbemycin) was effective against the gastrointestinal nematodes (PR > 90 %). In experiment 2, 48 suckling lambs were distributed in four randomized blocks (G1, G2, G3, and G4) by previous body weighings. G1 was kept as untreated control; G2 was treated following a FECRT-based schedule with drugs chosen based on fecal analysis (first drench with moxidectin, second drench with a combination of moxidectin and levamisole, and third drench with praziquantel, an anti-cestode drug); G3 and G4 received three drenches with ivermectin or disophenol, respectively. Body weighings and fecal analysis of these lambs were performed every 2 weeks over a 98-day period. An effective control of gastrointestinal nematodes was obtained with two nematicidal drenches following the FECRT-based schedule of treatments. On the other hand, eggs per gram of feces (EPG) counts were no different among untreated control, G3, and G4. Lambs treated using the FECRT-based schedule had the greatest liveweight gain among the groups tested. Additionally, liveweight gain was no different among the groups G3, G4, and G1. The FECRT-based schedule of anthelmintic treatments was beneficial regarding productivity and sustainability of helminth control in lambs infected by multidrug-resistant nematodes. [ABSTRACT FROM AUTHOR]