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Extraction of cellulose type I nanocrystals from cotton fibers was straightforwardly carried out using exclusively Brønsted acid-type ionic liquids (ILs) via a two-step swelling/hydrolysis route, the switch between these two stages being induced by water addition. Since the whole process was achieved in a single reaction medium predominantly based on 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) and 1-(4-sulfobutyl)-3-methylimidazolium hydrogen sulfate ([SBMIM]HSO 4), the process parameters were investigated in order to ensure a perfect compatibility and sequencing towards the two-step route proposed here. The impacts on nanoparticle morphology, crystallinity evolution, and cellulose type I to type II denaturation were observed under fieldemission gun scanning electron microscopy and corroborated by X-ray diffraction characterizations. ILs recovery and reuse were also demonstrated, opening up new prospects of conception of multicycle, environmentally and economically sustainable processes.

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Microcapsules processed by complex coacervation were prepared using hexadecane for the oil phase and glycinin (a soybean storage protein)-sodium dodecyl sulfate (SDS) as the main wall-forming material. The study underlines the essential role of SDS, which, by the way of [glycinin(+)-SDS(-)] insoluble complex formation, allowed the precipitation of proteins around oil droplets. Moreover, particular attention was attributed to the study of suitable conditions of glycinin cross-linking with glutaraldehyde. The reticulation step was performed at pH 4.0 and it was observed that the precipitated state of proteins increased considerably the efficiency of the cross-linking reaction. Analysis of the reactional medium after each main step of the process (emulsification, complex coacervation, cross-linking) allowed the follow-up and characterization of microcapsule formation. Optimization of different process parameters such as glycinin concentration, glycinin/SDS/glutaraldehyde ratios, pH and the kinetics of cross-linking allowed the encapsulation of the totality of oil and the use of more than 98% of initially introduced proteins for the microcapsule wall formation.

Developing waterborne polyurethane coatings from biobased polyols represents an interesting alternative, allowing at the same time to increase the use of sustainable renewable raw materials and to reduce volatile organic compounds emissions. In this work, biobased Veopur polyol was first functionalized with mercaptopropionic acid using solvent-free UV-mediated thiol-ene reaction performed in bulk. Grafted carboxylic moieties were then neutralized by triethylamine in order to obtain the required amphiphilic behavior. In the final step, functionalized water dispersible polyol was polymerized with water soluble polyisocyanate to form waterborne polyurethane (WPU). The influence of key-process parameters on grafting efficiency was investigated by iodometric titration, Fourier-transform infrared spectroscopy and proton nuclear magnetic resonance. Particle size measurements and stress-strain tests were carried out to characterize WPU water dispersions and corresponding materials, respectively.