Abstract. The usual sol-gel process was applied to precipitate silica or titania particles in a preformed poly(dimethylsiloxane) (PDMS) network under the presence of dibutyltin diacetate used as a catalyst. The resulting structures of the reinforcing fillers were studied by transmission electron microscopy and small-angle neutron scattering. Stress-strain measurements in elongation and equilibrium swelling experiments revealed distinct behaviors mainly attributed to the nature and the size of the generated particles and to the formation, in the case of titania, of a filler network even at low filler loadings.

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This work aims to develop a new ionic liquid, used as an aprotic green ä solvent, to dissolve kraft lignin from black liquor. The kraft lignin was extracted through precipitation with carbon dioxide at atmospheric pressure. 1,.0]undec-7-ene-based ionic liquids were obtained by quaternization of the nitrogen atom with a hydrogen atom or an alkyl chain. The yields of the synthesis of the ionic liquids varied between 76 and 80%. Dissolving experiments were carried out using the lignin isolated from the black liquor of a kraft process. Up to 20% (w/w) of the lignin can be dissolved in butyl-1,8 . The time it takes to dissolve the lignin in these three liquids shows that its solubility is influenced mostly by the nature of the cations. The lignin solubility was reduced in relation to the increased length of the grafted carbon chain. The thermogravimetric analysis (TGA) showed these liquids can be used as lignin solvents from room temperature up to 300 °C (onset of degradation). Steric exclusion chromatography showed a slight decrease (6%) in the molecular weight of the lignin dissolved in these ionic liquids.

Developing innovative industries in rural communities requires researching valuable finished products using local natural resources and feasible equipment and technology. Resources like seaweed are popular in today's global cosmetic ingredient and biotechnology market and are commonly found growing in remote communities, making it an ideal opportunity for rural economic development. This study focuses on the antioxidantrich polyphenol compounds found in the seaweed species Ascophyllum nodosum, local to Que´bec's North Shore coastline. Different processing technologies were compared to optimize polyphenol yields, including different preservation methods as well as bioextraction techniques that are applicable and accessible to remote regions. Analyses of extracts were performed using different colorimetric assays to measure total polyphenols and phlorotannins, as well as to estimate antioxidant activity. Results from the study found that the samples immediately frozen displayed higher polyphenol concentration and the highest antioxidant activity. Analysis also showed that a microwaveassisted extraction method improved polyphenol yield efficiency for water extractions. However, the conventional solvent extraction method using 75% (v/v aq.) 1,3-propanediol solvent resulted in the highest phenolic content, totalling 9.8% (w/w) of its dry weight, and the optimal antioxidant activity.

International audiencep-Toluenesulfonyl-lignin was prepared by reacting lignin with p-toluenesulfonyl chloride (TsCl) in an aqueous medium. The reaction was performed at 25 °C. The influence of several parameters on the reaction efficiency has been studied, including the ratio of p-toluenesulfonyl chloride/hydroxyl of lignin (TsCl/OH), the amount of triethylamine (Et3N), and the reaction time. The resulting p-toluenesulfonyl-lignin samples were characterized by means of scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDX), attenuated total reflection (ATR), and the X-ray photoelectron spectroscopy (XPS). Detailed structural characterization of the products, including elemental analysis, indicates that the synthetic approach leads to products without impurities. The tosylation reaction is complete after 24 h