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Jbilou F.,University of Lyon | Georgousopoulou I.-N.,National Technical University of Athens | Marinkovic S.,Agro industrie Recherches et Developpements | Vouyiouka S.,National Technical University of Athens | And 5 more authors.
European Polymer Journal | Year: 2016

Solid state post-polymerization (post-SSP) was performed on poly(butylene succinate) (PBS) commercial- and synthesized-grades and monitored for the first time by means of a fluorescent probe: (9-2-carboxy-2-cyanovinyl)julolidine or CCVJ. CCVJ is a molecular rotor and was simply incorporated in the PBS bulk (100 ppm) for fluorescent labelling. Post-SSP runs were then performed following a one- or two-step process. During the one-step process, CCVJ labelled PBS presented a moderate molecular weight (MW) increase (up to 1.15 times) along with a post-crystallization effect. Next, the SSP effectiveness was improved (in terms of MW- up to 4.2 times- and thermal characteristic upgrade) with the addition of a precrystallization step (two-step process). Labelled PBS showed a decrease of the CCVJ fluorescence intensity and a respective significant wavelength shift (blue shift) with SSP time. According to CCVJ calibration, this behavior was ascribed to the resultant MW increment and to the decrease of the acidic index (AI) during SSP. CCVJ was proven a reliable sensor able to act as a molecular rotor as well as a solvatochromic probe sensing both the molecular weight and polarity changes in the course of PBS SSP process. © 2016 Elsevier Ltd. All rights reserved. Source

Renault B.,Agro industrie Recherches et Developpements | Portella C.,CNRS Institute of Molecular Chemistry - Reims | Marinkovic S.,Agro industrie Recherches et Developpements | Estrine B.,Agro industrie Recherches et Developpements
Journal of Surfactants and Detergents | Year: 2012

Synthesis and surfactant properties and biodegradation of succinylated alkyl polyxylosides is described for the first time. The esterification of succinic anhydride with alkyl polyxylosides was achieved without solvent and the substitution degree controlled over a certain range. The surfactant properties were studied as a function of substitution degree. Their biodegradation was studied following OECD guidelines. The results have confirmed that the new synthetic approach described in this paper is a potentially economical and efficient method for the preparation of a new range of environmental friendly surfactants. © AOCS 2011. Source

Papaspyrides C.D.,National Technical University of Athens | Vouyiouka S.,National Technical University of Athens | Georgousopoulou I.-N.,National Technical University of Athens | Marinkovic S.,Agro industrie Recherches et Developpements | And 3 more authors.
Industrial and Engineering Chemistry Research | Year: 2016

Fossil-based and true bio-based poly(butylene succinate) (PBS) prepolymers were synthesized and submitted to solid-state polymerization (SSP) in the proximity of the polyester melting point (Tm), for reaction times up to 29 h under flowing nitrogen. SSP acted as a postcrystallization process, imparting an increase of the PBS melting point up to 126 °C from a starting Tm of 112-114 °C. Adding a precrystallization step prior SSP even resulted in a 2.5 times increase of the initial MW and a Tm shift up to 128 °C. Furthermore, the effect of most critical process parameters on the SSP feasibility and effectiveness was assessed, so as to launch an appropriate operation profile. End-group imbalance turned out to be the most significant key parameter for PBS polymerizability, and various attempts were made toward correcting it. Finally, SSP was examined as a PBS recycling technique and efficiently revived hydrolyzed PBS structures. © 2016 American Chemical Society. Source

Martel F.,Agro industrie Recherches et Developpements | Estrine B.,Agro industrie Recherches et Developpements | Plantier-Royon R.,University of Reims Champagne Ardenne | Hoffmann N.,University of Reims Champagne Ardenne | Portella C.,University of Reims Champagne Ardenne
Topics in Current Chemistry | Year: 2010

This review is dedicated to wheat hemicelluloses and its main components d-xylose and l-arabinose as raw materials for fine organic chemistry. The context of the wheat agro-industry, its by-products, and extraction and hydrolysis of hemicelluloses to produce the pentoses are considered. The straightforward preparation of pentose-based surfactants, their properties, and their situation in the field of carbohydrate-based surfactants are addressed. Multistep transformations of pentoses are also described, first from a methodology point of view, with the aim of producing multifunctional enantiopure building-blocks, then considering targeted natural and/or bioactive products. Selected reactions of furfural, an important dehydration product of pentoses, are also presented. © 2010 Springer-Verlag Berlin Heidelberg. Source

Ludot C.,Agro industrie Recherches et Developpements | Ludot C.,CNRS Institute of Molecular Chemistry - Reims | Estrine B.,Agro industrie Recherches et Developpements | Le Bras J.,CNRS Institute of Molecular Chemistry - Reims | And 3 more authors.
Green Chemistry | Year: 2013

Sulfoxides and sulfones as solvents have been used for the glycosidation of various carbohydrates with decanol in the absence of an added catalyst. The production of decyl-d-xylosides has been studied in dimethylsulfoxide and the importance of parameters such as pressure and temperature on the reaction time has been pointed out. Organic acids produced by carbohydrate caramelization highly influenced the glycosidation kinetics. Other sulfur containing solvents were also effective. A decanol-sulfolane biphasic reaction medium has been designed for the production of decyl-d-xylosides in short reaction times and yields up to 83%. Sulfolane has been easily recovered by liquid-liquid separation and reused in the next three glycosidation reactions without any yield decrease. © 2013 The Royal Society of Chemistry. Source

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