Jean-François Le Nest

Chemical and rheological characterizations of some vegetable oils derivatives commonly used in printing inks

Abstract This study concerns the characterization of vegetable oils and some of their derivatives which are commonly used in offset printing ink formulations. Chemical and rheological characterizations were performed in order to gain a better insight into their structure/properties relationships. The aim of this study was therefore to improve the quality and performance of printing inks on the basis of sound scientific criteria rather than empirical notions.

Polymer electrolytes derived from chitosan/polyether networks

Polysaccharides like cellulose and chitosan are well known for their aptitude to generate thin films. This paper reports the synthesis and characterization of oxipropylated chitosan and their reaction with oligoether-based mono and di-isocyanate. The resulting networks, containing LiN (CF 3 SO 2 ) 2 , were investigated by differential scanning calorimetry and complex impedance measurements.

A novel solid polymer electrolyte : synthesis and characterization

SummaryA new polyether network was prepared using a polyethylene oxide (PEO) triol and a PEO diisocyanate, the latter component arising from the chemical modification of commercial PEO diamines. The physico-chemical properties of the network alone and with LiClO4 were assessed in comparison with those of previously obtained structures. Ionic conductivities were found to be higher with this new system. Replacement of LiClO4 by LiN(CF3SO2)2 improved the conductivity further because of the plasticizing role of the imidic anion.

Polymer Electrolytes Derived from Hydroxiethylcellulose/Polyether Films

Abstract Polysaccharides, like cellulose and its derivatives, can be used in polymer electrolytes because of their aptitude to generate thin films. This paper reports the reaction of hydroxyethylcellulose with oligoether-based diisocyanates. The resulting networks were investigated by differential scanning calorimetry and infrared spectroscopy.

A novel approach to crosslinked polymer electrolytes based on polyethers: network formation via photochemistry

This communication describes a novel approach to crosslinking functionalized oligoether chains based on the photochemical irradiation of their terminal chromophores bearing conjugated furan moieties. The interest of this study resides in the possiblity of preparing polymer electrolytes which can be handled as thermoplastic materials and crosslinked only at the last stage of their processing, e.g. as thin films.

Hidroxietil celulose enxertada com poliéteres

Commercial samples of hydroxyethyl cellulose (HEC) were characterized by 1H and 13C NMR, FTIR and viscosimetry, in order to obtain their average molar substitution (MS), average degree of substitution (DS) and average degree of polymerization (DP). Commercial samples of poly(ethylene oxide) diamines (POE) and poly(propylene oxide) diamines (POP) were also characterized before being converted into their corresponding diisocyanates. The networks were obtained by the condensation reaction of each HEC with the diisocyanates. The products were characterized by FTIR, UV-Vis, X-ray diffraction and also DSC to determine the glass transition temperatures.

New family of polymer electrolytes based on cellulosic precursors

A brief review is given of the fundamental features determining the behavior of amorphous PEO-based networks as polymer electrolytes containing ionic moieties in terms of two basic issues affecting the ultimate optimum ionic conductivity, viz. the factors determining the extent of ionic dissociation and those influencing the ionic mobility. These generalizations deduced from previous studies on a variety of systems allowed the elaboration of a new family of structures based on polysaccharides cross-linked with PEO and grafted with polyether chains. The preliminary results described in this paper are promising in view of the application of these materials in solid-state batteries because of their good electrochemical properties combined with mechanical strength and film-forming aptitude.