Determination of the degree of substitution (DS) of mixed cellulose esters by elemental analysis

Equations for transforming the results of elemental analysis (EA) into degree of substitution (DS) values for aliphatic cellulose esters were developed. The equations allow to determine the DS of cellulose derivatives bearing not only one but also two different acyl substituents. Error transmission studies revealed that the accuracy of the DS-values for a pure sample depends on both the number of carbon atoms in the substituents and on the uncertainty of the EA, especially from the hydrogen content. This method provides accurate DS-values (± 0.10 in most cases) if H-content determinations are within ± 0.1

La lipochimie et le carbone renouvelable : une opportunité pour l’agro-industrie

The willing of the Member States of the European Union to reduce the petrol dependence, associated to the environment quality problems and the search for better life conditions for citizens sets the lipochemistry within the expectations of the sustainable development and within the hopes of our society. The agriculture will thus play a capital role in the coming years. Indeed, the oleaginous will have a more and more privileged position to reply of course to the energy requirements but also mainly to supply specialty and commodity bio-products. In these conditions, the industry of the renewable carbon, and particularly the industry of oleaginous, are going to develop and will come across an expansion in the short and the medium term. In this new context, the synergy between different disciplines will be a provider of success. Also, the “assembling” of different agricultural productions will be a source of innovation and a basis for the creation of new economic activities. In this sense, the reactivity between the lignocellulosic substrates and the fatty derivatives constitutes one of these challenges. We have investigated new activation techniques adapted to two-phase solid/liquid media. These activations employ either technological ways that favour the compatibility between products and substrates, or fatty derivatives that provide a good reactivity after appropriate functionalisation. The examples that are given try to illustrate this approach, to debate around new concepts, and to place emphasis on all the scientific and economic benefits obtained therefrom. From then on, the lipochemistry is situated in the centre of a system where the deductive research and the inductive research nourish each other

Synthesis of new diesters of 1,4:3,6-dianhydro-d-glucitol by esterification with fatty acid chlorides

International audienceA new series of esters was prepared by esterification of 1,4:3,6-dianhydro-o-glucitol with long chain fatty acid chlorides. The experimental conditions prevented thermal degradation of the sugar and led to diesters with a high degree of purity. The final products were readily isolated and characterized by IR and NMR. Molecular modelling confirmed that the exo and endo configurations of the o-alkyl groups of the diesters of isosorbide were retained. This work reports a novel synthesis of diesters of natural origin which shows promise in environmentally sensitive applications, such as phytosanitory adjuvants, requiring biodegradable materials as replacements for fossil-derived products

Huile adjuvante : devenir des esters méthyliques dans le sol

International audienceThe fate of vegetal oil, ofeic acid methyl ester, in soil was investigated and compared ta that of a minerai oil. Experiments were both carried out in laboratory conditions (sol/ columns or lysimeters) and in field conditions. A microbiology study was performed using the same soil. Vegetal and mineral oils were applied an soil of lysimeter or field ot the phytosanitary application dose. Migration and primary degradation profiles of the oils and their metabolites were determined during a period of 120 days by gas chromatography analysis. Results showed a total degradation of the vegetal oil and its metabofites after 60 days whereas mineral oil required 90 days. A microbiology study was performed to identify some micro-organisms of the soi! and to evaluate ecotoxicity effects of the oils. Vegetal oil was revea/ed ta be Jess taxie thon minerai oil even at high concentration. The high biodegradability of the vegetal ester in soil was confirmed as well as their environmental qualities

Synthesis of new diesters of 1,4:3,6-dianhydro-d-glucitol by esterification with fatty acid chlorides

A new series of esters was prepared by esterification of 1,4:3,6-dianhydro-o-glucitol with long chain fatty acid chlorides. The experimental conditions prevented thermal degradation of the sugar and led to diesters with a high degree of purity. The final products were readily isolated and characterized by IR and NMR. Molecular modelling confirmed that the exo and endo configurations of the o-alkyl groups of the diesters of isosorbide were retained. This work reports a novel synthesis of diesters of natural origin which shows promise in environmentally sensitive applications, such as phytosanitory adjuvants, requiring biodegradable materials as replacements for fossil-derived products

Huile adjuvante : devenir des esters méthyliques dans le sol

The fate of vegetal oil, ofeic acid methyl ester, in soif was investigated and compared ta that of a minerai oil. Experiments were bath carried out in laboratory conditions (soi/ columns or lysimeters) and in field conditions. A microbiology study was performed using the same soi/. Vegetal and minerai oils were applied an soi/ of lysimeter or field ot the phytosanitary application dose. Migration and primary degradation profiles of the oils and their metabolites were determined during a period of 120 days by gas chromatography analysis. Results showed a total degradation of the vegetal oil and its metabofites after 60 days whereas minerai oil required 90 days. A microbiology study was performed to identify some micro-organisms of the soi! and to evaluate ecotoxicity effects of the oils. Vegetal oil was revea/ed ta be Jess taxie thon minerai oil even at high concentration. The high biodegradability of the vegetal ester in soi/ was confirmed as we/1 os their environmental qua'Jities

Fate in the soil of an oil additive of plant origin

The methyl ester of oleic acid, a plant oil derivative, can be used as an additive oil for pesticides. We compared the biodegradability in soil of this oil with that of a mineral oil by means of laboratory experiments using lysimeters of 70 cm height × 20 cm diameter. The migration in soil of the oils and of the metabolites of the plant ester over 120 days was examined by gas chromatography and liquid chromatography. The plant oil and its metabolites were completely degraded within 60 days, whereas degradation of the mineral oil required 90 days. The molecules did not migrate far into the soil and therefore presented no risk of contaminating groundwater

Procédé pour conférer un caractère hydrophobe à une matière solide cellulosique ou amylacée

L'invention concerne un procédé pour conférer un caractère hydrophobe à une matière solide cellulosique ou amylacée, du type dans lequel on greffe un corps gras sur les fonctions alcool de la matière cellulosique ou amylacée. Selon l'invention, on réalise le greffage (a) en mettant la matière cellulosique ou amylacée en suspension dans une phase liquide composée d'un acide gras ou d'un ester d'acide gras, (b) en agitant le milieu hétérogène en présence d'un catalyseur basique pour réaliser une mise en contact des phases, (c) et en soumettant le milieu hétérogène à une irradiation micro-ondes de façon à le porter à une température comprise entre 150 DEG C et 210 DEG C pendant une durée comprise entre 30 secondes et 30 minutes. Le procédé de l'invention permet de rendre hydrophobe une matière cellulosique ou amylacée sans utilisation de solvants toxiques

La lipochimie et le carbone renouvelable : une opportunité pour l’agro-industrie

The willing of the Member States of the European Union to reduce the petrol dependence, associated to the environment quality problems and the search for better life conditions for citizens sets the lipochemistry within the expectations of the sustainable development and within the hopes of our society. The agriculture will thus play a capital role in the coming years. Indeed, the oleaginous will have a more and more privileged position to reply of course to the energy requirements but also mainly to supply specialty and commodity bio-products. In these conditions, the industry of the renewable carbon, and particularly the industry of oleaginous, are going to develop and will come across an expansion in the short and the medium term. In this new context, the synergy between different disciplines will be a provider of success. Also, the “assembling” of different agricultural productions will be a source of innovation and a basis for the creation of new economic activities. In this sense, the reactivity between the lignocellulosic substrates and the fatty derivatives constitutes one of these challenges. We have investigated new activation techniques adapted to two-phase solid/liquid media. These activations employ either technological ways that favour the compatibility between products and substrates, or fatty derivatives that provide a good reactivity after appropriate functionalisation. The examples that are given try to illustrate this approach, to debate around new concepts, and to place emphasis on all the scientific and economic benefits obtained therefrom. From then on, the lipochemistry is situated in the centre of a system where the deductive research and the inductive research nourish each other

La bioéconomie et la croissance verte

National audienc