Etude des conditions de synthèse et des propriétés d'ASA (anhydrides alkényles succiniques) d'esters d'huiles végétales - Application à l'industrie papetière

De nouveaux agents de collage d'origine naturelle pour le papier d'écriture ont été obtenus par réaction entre l'anhydride maléique et des esters d'huiles végétales notamment des oléates d'alkyles. Ils appartiennent à la famille des anhydrides alkényles succiniques (ASA). L'hydrophobation du papier, qui limite la pénétration de l'eau, repose sur la réaction entre les fonctions hydroxyles de la cellulose et la fonction anhydride de l'ASA. Les ASA végétaux (oléo-ASA) sont caractérisés par une composition maximale en chaînes C18:1 et une fonction ester terminale variable. Trois ASA végétaux ayant des motifs esters en C2 ou C3 présentent un collage et un comportement en émulsion comparables à ceux des ASA pétrochimiques, utilisés dans l'industrie. Leur hydrolyse en diacide est deux fois plus lente et leur résistance au phénomène de stripping dix fois plus importante. Ces avantages en font d'excellents candidats à la substitution des ASA d'origine fossile. Après avoir optimisé la synthèse et la purification de ces trois composés, l'ASA issu d'oléate de propyle a été testé, avec succès, comme agent de collage à l'échelle pilote sur une tonne de papier. Outre l'application en papeterie, les oléo-ASA issus d'oléates d'alkyles de motifs esters variables pourraient trouver des débouchés dans d'autres domaines. Une base de données de propriétés a été acquise au travers de caractérisations physico-chimiques permettant d'établir des corrélations structure-propriétés. Le greffage du motif anhydride, le passage d'une configuration cis à trans lors de la ène-réaction et la longueur du motif ester, influencent les caractéristiques des oléo-ASA

Etude des conditions de synthèse et des propriétés d'ASA (anhydrides alkényles succiniques) d'esters d'huiles végétales - Application à l'industrie papetière

De nouveaux agents de collage d'origine naturelle pour le papier d'écriture ont été obtenus par réaction entre l'anhydride maléique et des esters d'huiles végétales notamment des oléates d'alkyles. Ils appartiennent à la famille des anhydrides alkényles succiniques (ASA). L'hydrophobation du papier, qui limite la pénétration de l'eau, repose sur la réaction entre les fonctions hydroxyles de la cellulose et la fonction anhydride de l'ASA. Les ASA végétaux (oléo-ASA) sont caractérisés par une composition maximale en chaînes C18:1 et une fonction ester terminale variable. Trois ASA végétaux ayant des motifs esters en C2 ou C3 présentent un collage et un comportement en émulsion comparables à ceux des ASA pétrochimiques, utilisés dans l'industrie. Leur hydrolyse en diacide est deux fois plus lente et leur résistance au phénomène de stripping dix fois plus importante. Ces avantages en font d'excellents candidats à la substitution des ASA d'origine fossile. Après avoir optimisé la synthèse et la purification de ces trois composés, l'ASA issu d'oléate de propyle a été testé, avec succès, comme agent de collage à l'échelle pilote sur une tonne de papier. Outre l'application en papeterie, les oléo-ASA issus d'oléates d'alkyles de motifs esters variables pourraient trouver des débouchés dans d'autres domaines. Une base de données de propriétés a été acquise au travers de caractérisations physico-chimiques permettant d'établir des corrélations structure-propriétés. Le greffage du motif anhydride, le passage d'une configuration cis à trans lors de la ène-réaction et la longueur du motif ester, influencent les caractéristiques des oléo-ASA. ABSTRACT : New sizing agents from natural origin were obtained by reaction between maleic anhydride and esters from vegetable oils and mainly alkyl oleates. They belong to the alkenyl succinic anhydrides family (ASA). Paper hydrophobation, which limits water penetration, relies upon the reaction between the hydroxyl fonctions of cellulose and the anhydride moiety of ASA. Vegetable ASA (oleo-ASA) are characterized by a maximum composition in C18:1 and a varying terminal ester moiety. Three oleo-ASA, with an ester moiety in C2 or C3, presented a sizing and an emulsion behaviour equivalent to the one obtained with petrochemical ASA, used in industry. Their hydrolysis in diacid is two-fold slower and their resistance to stripping phenomenon is ten-fold higher. These advantages make them excellent candidates to the substitution of ASA from fossil origin. Once the synthesis and purification of the three preceeding molecules optimized, the ASA from propyl oleate has been successfully tested as sizing agent at a 100 kg of paper pilot scale. Apart from the application in papermills, ASA from alkyl oleates with varying ester moieties might find opportunities in other fields. A properties database has been acquired by the physico-chemical characterizations, that have allowed us to establish structure-properties relations. The grafting of anhydride moiety, the change from a cis configuration to a trans configuration during the ene-reaction and the ester moiety's length influence the oleo-ASA characteritics

Recovery of hydroxycinnamic acids from renewable resources by adsorption on zeolites

The aim of the study is to examine the adsorption capacity of hydroxycinnamic compounds (ferulic acid, p-coumaric acid, cinnamic acid) on zeolite adsorbents (FAU- and *BEA-type structure) versus Amberlite resin XAD16. The pH and contact time effects on adsorption were evaluated. The adsorption capacity was dependent on pH and higher at pH less than pKa1. The kinetic adsorption is faster onto FAU and *BEA zeolites than onto XAD16 resin. Maximum adsorption capacities were calculated for the target compounds for pH=3.5 by using the Langmuir isotherm model. They reached higher values for zeolites than for XAD16 and are respectively of 139, 122 and 109 mg g-1 for ferulic, p-coumaric and cinnamic acids. Values around 30 mg g-1 were observed for XAD16. Desorption ratios are close to 100 % for *BEA zeolite and XAD16 resin in the presence of ethanol 96 %. The use of regenerated zeolites leads to a loss of adsorption capacities of 30 % for the cinnamic acid and 20 % for the two other acids. It was concluded that *BEA zeolites are particularly interesting adsorbants to isolate the hydroxycinnamic compounds from vegetal extracts

Synthesis and characterization of oleic succinic anhydrides: Structure-property relations

Alkenyl succinic anhydrides (ASA) were prepared by an‐ene reaction of n‐alkyl (C1 to C5) oleates with maleic anhydride. The purified compounds were characterized by FTIR, 1H NMR, and MS analytical methods to elucidate their structures. Their physicochemical properties were systematically studied and found to depend on the length of the alkyl radical. Structure‐property relations were established for viscosity, m.p., and density. The combination of a long hydrophobic chain and a highly polar group with density values close to that of water implied good emulsification properties for some of these molecules. Comparison of the thermal properties of alkyl oleates and their respective ASA demonstrated that the grafting of maleic anhydride allowed the synthesis of compounds with very low melting temperatures (less than −60°C) and good stability at high temperatures (greater than 350°C) under both air and helium atmospheres. All these properties suggest a strong potential for application in the biolubricant or surfactant fields. The combined influences of the succinic part and variable ester moieties imply that each ASA molecule has its own characteristics, based on which applications could be developed

Synthesis of alkenyl succinic anhydrides from methyl esters of high oleic sunflower oil

Alkenyl succinic anhydrides (ASA) have been prepared by ene‐reaction of high‐oleic sunflower oil methyl esters with maleic anhydride in a 50% xylene medium. Response surface methodology (RSM) was used to investigate the influence of two factors: reaction temperature and molar ratio between maleic anhydride (MA) and methyl esters (SME). The studied parameters in 8‐h reactions were the methyl oleate conversion, the distillation yield in ASA, and responses allowing the indirect estimation of side reaction products: clarity index and dynamic viscosity. The highest yield in ASA (>70%; clarity index ≈10) was reached for a temperature of 240–250 °C with a molar ratio of 1.5–1.7. But for an industrial application requiring minimized side products (clarity index >40), the optimal synthesis conditions were: temperature between 220 and 235 °C and molar ratio of 1.2–1.35 (yield ≈55%). Such conditions did not provide a medium free of side products, even if xylene decreased their formation. Compared to solvent‐free synthesis, conversion was lower with xylene. With solvent, higher temperatures were needed to reach the same yields. Supplementary heating compensated the reagent dissolution effect that slows down the kinetics of the ene‐reaction. The influence of reaction time at 220 °C with a MA/SME ratio of 1.2 in a 50% xylene medium was studied. A reaction time of 8–10 h provided a good compromise between ASA yield and side products

Kinetics and mechanism of the reaction between maleic anhydride and fatty acid esters and the structure of the products

Alkenyl succinic anhydrides (ASA) were obtained by reaction between maleic anhydride and high‐oleic sunflower oil (HOSO) esters. A kinetics study of the maleinization of alkyl esters indicated that the maleinization reaction was second order overall and first order with respect to the individual reactants, and the activation energy was 77.2 ± 3.3 kJ/mol in the investigated temperature range (185–225 °C). These results showed that the cis configuration and the central position of the double bond in HOSO esters facilitate the maleinization of the latter. On the contrary, the length of the linear ester moiety had no influence on the course of the maleinization reaction. Moreover, new evidence demonstrates that there are two different reaction mechanisms: ene‐reaction and addition in allylic position with a 2 : 1 ratio, respectively. This ratio was constant throughout the reaction, thus indicating that these mechanisms are independent

Thermo-mechano-chemical extraction of hydroxycinnamic acids from industrial hemp by-products using a twin-screw extruder

This work aims at developing a continuous intensified green process to extract high-value added molecules from industrial hemp by-products. Hemp hurds and hemp dust were studied as potential sources for the production of two hydroxycinnamic acids (HCA): ferulic (FA) and p-coumaric acids (p-CA). Prior to pilot scale extraction, FA and p-CA analytical contents were evaluated to 0.3 and 3.5g/kg dry matter (DM) for hemp hurds and 0.1 and 0.8g/kg DM for hemp dust as potentials of reference. The continuous pilot scale extraction was then carried out using twin-screw extrusion. Mild conditions were developed: 50°C, alkaline aqueous or hydroalcoholic solvent (less than 0.5M NaOH) and low liquid to solid ratios. The mechanical effect helps the diffusion of the solvent, promotes the hydrolysis of the ester and ether bonds and favors the extraction of HCA in a short time. Yields in p-CA and FA reached 50% and 33% of the free and bound contents for hemp hurds. For hemp dust, all of p-CA was extracted whereas 60% of FA was recovered. The solid residue may be submitted to a second extraction stage with a polar solvent in order to increase HCA recovery. Extraction by extrusion could be seen as an alternative green processing technique as it is responsible for a reduction of extraction time and energy and a decrease in solvent and reagent consumptions

Synthesis of high-molecular-weight multifunctional glycerol polyhydroxyurethanes PHUs

Glycerol carbonate acrylate is a 5-membered cyclic carbonate synthesized from glycerol that is used as a chemical coupling agent and has proven highly suitable for use in the synthesis of multifunctional polyhydroxyurethanes (PHUs). The multifunctionality of the structure of PHUs is determined by the density of the carbon-amine groups generated by the Aza-Michael reaction and that of the urethane groups and adjacent primary and secondary hydroxyl groups generated by aminolysis. Glycerol carbonate acrylate is polymerized with polyfunctional mono-, di-, tri, and tetra-amines, by type-AB polyaddition, either in bulk or in solution, through stepwise or one-pot reaction strategies in the absence of added catalysts. These approaches result in the generation of linear, interchain, and crosslinked structures, through the polyaddition of linear and branched amines to the ethylene and cyclic carbonate sites of glycerol carbonate acrylate. The resulting collection of organic molecules gives rise to polyethylene amino ester PHUs with a high molar mass, exceeding 20,000 g·mol(-1), with uniform dispersity

Aminolysis Reaction of Glycerol Carbonate in Organic and Hydroorganic Medium

Aminolysis reaction of glycerol carbonate with primary amine in organic and hydroorganic media leads to the formation of two hydroxyurethane isomers and a partial decomposition of glycerol carbonate into glycerol. Aminolysis with a secondary amine promotes the condensation reaction and limits the formation of glycerol. The ratio of α versus β was determined by zgig 13C NMR. This technique permits computing the yield of α and β products in the medium. The quantity of glycerol was determined by GC analysis. The ratio of the isomers and the amount of glycerol depend on the amine and the solvent. Kinetic investigations reveal that, in hydroorganic medium, the more the alkyl chain of the amine increased, the less glycerol was formed. On the contrary, in organic medium, the alkyl chain of the amine does not play a major role in the formation of glycerol

From petrochemical polyurethanes to biobased polyhydroxyurethanes

From a green and sustainable chemistry standpoint, the current challenge in the polyurethane's industry is to switch from petrobased polyurethanes (PUs) to biobased polyhydroxyurethanes (PHUs). This review describes the main alternative strategies being developed with a focus on PHUs from vegetable oils and derivatives. The substitution of petrobased polyols by natural oil based polyols was the first route to biobased PUs to be developed. The second strategy involves synthesis without the need of harmful isocyanate by the nucleophilic polyaddition of polyamines to polycyclic carbonates. The technological barrier to the synthesis of biobased cyclic carbonates could be overcome by the chemical transformation of epoxidized vegetable oils or by the use of glycerine carbonate-based intermediates. New families of biobased PHUs with a lower environmental footprint could be generated