Six commercial oil-proof paper specimens, which had been manufactured with application of a new t... more Six commercial oil-proof paper specimens, which had been manufactured with application of a new type of fluorochemical agent on their surface, were evaluated in terms of waterand oil-proof and printing properties.The new agent had been designed to comply with standards requiring six or fewer carbons in the perfluorinated alkyl chain. First, the paper samples were characterized in terms of classical properties, such as their thickness, density and ash content. The ashes were collected after the calcination of the paper samples and their contents were found to be around 15-17 wt%. The elemental analysis of these minerals indicated that they were inorganic fillers and pigments (Aland Si-based). No traces of fluorine components were detected in this mineral part, because the fluorochemicals used in the oil-proof papers were organic-based molecules, which underwent total combustion during the calcination process. Stöckigt sizing and Cobb60 tests clarified that all the paper samples had c...
Abstract Polypyrrole was chemically synthesised by using, for the first time, Birchwood xylan as ... more Abstract Polypyrrole was chemically synthesised by using, for the first time, Birchwood xylan as additive, and ammonium peroxydisulfate (APS) as oxidant. The impact of additive concentration, polymerisation time and reagents concentration on PPy conductivity was ...
Abstract The study of the dynamics of capillary wetting has started in the 1920s with the studies... more Abstract The study of the dynamics of capillary wetting has started in the 1920s with the studies of Lucas, Washburn, and Rideal. The LWR law states a square root dependency with time for the penetration distance. This property was shown to be valid for arbitrary, uniform cross section microchannels. However, the dynamics of capillary wetting in non-uniform cross section channels is still a subject of investigation. In this work an analytical model for piecewise varying cross section channels is developed. It is shown that the model compares favorably to experiments. Moreover the results are also in agreement with a former numerical approach.
ABSTRACT The effect of the molecular structure on the reactivity of four first-generation linear-... more ABSTRACT The effect of the molecular structure on the reactivity of four first-generation linear-dendritic block copolymers derived from Jeffamines and bearing amine end groups is presented and discussed. Different parameters were investigated via chemical modifications and nuclear magnetic resonance analysis, showing that chain length, hydrophilic/ hydrophobic character, and flexibility of the central oligoether block did not produce any change in the amine moiety reactivity. In contrast, the type of branches and the nature of the amine end groups strongly affected the reactivity in an unusual manner. In fact, the copolymer bearing aromatic amine end groups showed better reactivity than those based on aliphatic counterparts.
... MN Belgacem ∗ , MC Salon-Brochier, M. Krouit and J. Bras Laboratoire de Génie des Procédés Pa... more ... MN Belgacem ∗ , MC Salon-Brochier, M. Krouit and J. Bras Laboratoire de Génie des Procédés Papetiers (LGP2), UMR CNRS 5518 Grenoble INP Pagora, Domaine Universitaire, 461 rue de la papeterie ... My has a higher reactivity than LM, as it contains more double bonds. ...
Samples of Pinus sylvestris were treated with different reagents bearing isocyanate, carboxylic a... more Samples of Pinus sylvestris were treated with different reagents bearing isocyanate, carboxylic anhydride or oxirane functions to induce reaction with the OH groups of the various components of wood. Conditions were optimised to achieve maximum grafting. When the reagents also carried a polymerisable function, a monomer (styrene or methyl methacrylate) was incorporated into the wood morphology after the derivatisation reaction. Subsequent radical polymerisation produced chemical incorporation of some of the resulting macromolecules. The properties of the doubly modified samples were assessed using a wide variety of tests. Both the hydrophobic character and the density increased considerably, suggesting improved lifetime and extended domains of application.
Soda lignin precipitated from black liquor of Stipa tenacissima L. cooking was converted into pol... more Soda lignin precipitated from black liquor of Stipa tenacissima L. cooking was converted into polyols by a chain extension reaction with propylene oxide (PO). It was oxypropylated in a batch reactor in the presence of potassium hydroxide (KOH) as a catalyst. The reaction conditions were optimized by modifying the lignin/propylene oxide ratio [L/PO (w/v)], the temperature and the catalyst content. L/PO ratios of 20/80, 30/70 and 40/60 and catalyst contents from 3% to 5% were used. The temperature of the reaction was varied from 120 to 140 °C. The ensuing polyols were characterized by FTIR, H-NMR spectroscopy and size exclusion chromatography. Also, their viscosity and hydroxyl index were determined. A decrease in the molecular weight was observed after the oxypropylation reaction, which was explained by lignin depolymerisation. The viscosity and the hydroxyl index of the polyols ranged from 0.48 to 4.2 Pa.s and 150 to 375, depending on the lignin/PO ratio. Rigid polyurethane foam (RP...
ABSTRACT Commercial oil-proof papers containing new family of fluorochemicals were characterized ... more ABSTRACT Commercial oil-proof papers containing new family of fluorochemicals were characterized in terms of surface and barrier properties and printability. XPS analyses demonstrated that the fluorochemicals added to these papers had shorter perfluoroalkyl chains, compared to those used few decades ago. Contact angle measurements were performed and the obtained data were processed according to Owens–Wendt–Rabel–Kaelble (OWRK) approach, in order to calculate the surface energy of the investigated samples. This set of experiments revealed that the values of the surface energy of the non-coated surfaces of oil-proof papers were low enough (i.e. about 5 mJ/m2) to repel both water and oil. The surface energy of the coated sides was, instead, close to that of classical organic surfaces (i.e. around 30 mJ/m2), which predicts their potentially good printability. In fact, microcontour test was performed as the basic test for evaluating printability of oil-proof papers and showed that ink pigment retention was not significantly influenced by the level of barrier to oil. However, the surface roughness was found to play a key role in such properties.
La synthese et la caracterisation (ir, rmn #1h et #1#3c, dsc, atg, spectrometrie de masse et tono... more La synthese et la caracterisation (ir, rmn #1h et #1#3c, dsc, atg, spectrometrie de masse et tonometrie) de mono- et diurethanes furaniques obtenus par condensation d'un di- ou monoalcool avec un di- ou monoisocyanate ont ete etudiees. Il apparait que l'atome d'hydrogene en position c5 du noyau furanique n'intervient pas lors de cette reaction de condensation. Une grande gamme de structures a ete exploree quant a la nature et la position des substituants tant au niveau des alcools qu'au niveau des isocyanates. Une etude cinetique realisee dans un but comparatif, avec ces memes produits, a permis de situer la reactivite des composes furaniques par rapport a ses homologues des series aliphatique et aromatique. Il s'est avere que les isocyanates de la serie furanique sont plus reactifs que ceux des autres series, alors que les alcools furaniques ont une reactivite semblable aux alcools benzyliques. Les alcools aliphatiques sont nettement plus reactifs. Une etude...
Chitin nanocrystals (ChNCs) and chitin nanofibers (ChNFs) are nanomaterials with great innovative... more Chitin nanocrystals (ChNCs) and chitin nanofibers (ChNFs) are nanomaterials with great innovative potential for sustainable applications in academic and industrial fields. The research related to their isolation and production, characterization, and utilization is still new. The aim of this study is to investigate the effects of the production process on the morphology and properties of ChNFs and ChNCs produced from the same source of chitin. ChNCs were prepared by acid hydrolysis of commercial shrimp shell α-chitin, and ChNFs were prepared by mechanical defibrillation using closed loop supermass colloidal grinding. Differences in their shape, size, and crystallinity were observed. ChNFs were observed to have higher aspect ratio, higher viscosity, and better thermal stability than ChNCs. Although the ChNC casting film had a higher degree of transparency, it had lower mechanical properties than ChNF film. In addition, the capacities of each nanomaterial for producing Pickering emulsi...
The invention relates to a method for marking paper, particularly cigarette paper, including the ... more The invention relates to a method for marking paper, particularly cigarette paper, including the following steps: forming an iridescent cellulose nanocrystal film from cellulose nanoparticles, dry-grinding the film into grains, incorporating the grains to serve as pigments in an aq. mixt. contg. a binder, coating the paper with the aq. mixt., and drying; wherein the step of forming the film includes three main sub-steps: manufg. cellulose nanocrystals (CNC), placing same in suspension and forming a film; and wherein, during the sub-step of manufg. cellulose nanocrystals (CNC), cellulose nanoparticles, having an elongate rod-like morphol., a form factor of 20 to 70, preferably 40 to 60, and a polydispersity index (PDI) of less than 0.1 are used as a starting material. [on SciFinder(R)]
Six commercial oil-proof paper specimens, which had been manufactured with application of a new t... more Six commercial oil-proof paper specimens, which had been manufactured with application of a new type of fluorochemical agent on their surface, were evaluated in terms of waterand oil-proof and printing properties.The new agent had been designed to comply with standards requiring six or fewer carbons in the perfluorinated alkyl chain. First, the paper samples were characterized in terms of classical properties, such as their thickness, density and ash content. The ashes were collected after the calcination of the paper samples and their contents were found to be around 15-17 wt%. The elemental analysis of these minerals indicated that they were inorganic fillers and pigments (Aland Si-based). No traces of fluorine components were detected in this mineral part, because the fluorochemicals used in the oil-proof papers were organic-based molecules, which underwent total combustion during the calcination process. Stöckigt sizing and Cobb60 tests clarified that all the paper samples had c...
Abstract Polypyrrole was chemically synthesised by using, for the first time, Birchwood xylan as ... more Abstract Polypyrrole was chemically synthesised by using, for the first time, Birchwood xylan as additive, and ammonium peroxydisulfate (APS) as oxidant. The impact of additive concentration, polymerisation time and reagents concentration on PPy conductivity was ...
Abstract The study of the dynamics of capillary wetting has started in the 1920s with the studies... more Abstract The study of the dynamics of capillary wetting has started in the 1920s with the studies of Lucas, Washburn, and Rideal. The LWR law states a square root dependency with time for the penetration distance. This property was shown to be valid for arbitrary, uniform cross section microchannels. However, the dynamics of capillary wetting in non-uniform cross section channels is still a subject of investigation. In this work an analytical model for piecewise varying cross section channels is developed. It is shown that the model compares favorably to experiments. Moreover the results are also in agreement with a former numerical approach.
ABSTRACT The effect of the molecular structure on the reactivity of four first-generation linear-... more ABSTRACT The effect of the molecular structure on the reactivity of four first-generation linear-dendritic block copolymers derived from Jeffamines and bearing amine end groups is presented and discussed. Different parameters were investigated via chemical modifications and nuclear magnetic resonance analysis, showing that chain length, hydrophilic/ hydrophobic character, and flexibility of the central oligoether block did not produce any change in the amine moiety reactivity. In contrast, the type of branches and the nature of the amine end groups strongly affected the reactivity in an unusual manner. In fact, the copolymer bearing aromatic amine end groups showed better reactivity than those based on aliphatic counterparts.
... MN Belgacem ∗ , MC Salon-Brochier, M. Krouit and J. Bras Laboratoire de Génie des Procédés Pa... more ... MN Belgacem ∗ , MC Salon-Brochier, M. Krouit and J. Bras Laboratoire de Génie des Procédés Papetiers (LGP2), UMR CNRS 5518 Grenoble INP Pagora, Domaine Universitaire, 461 rue de la papeterie ... My has a higher reactivity than LM, as it contains more double bonds. ...
Samples of Pinus sylvestris were treated with different reagents bearing isocyanate, carboxylic a... more Samples of Pinus sylvestris were treated with different reagents bearing isocyanate, carboxylic anhydride or oxirane functions to induce reaction with the OH groups of the various components of wood. Conditions were optimised to achieve maximum grafting. When the reagents also carried a polymerisable function, a monomer (styrene or methyl methacrylate) was incorporated into the wood morphology after the derivatisation reaction. Subsequent radical polymerisation produced chemical incorporation of some of the resulting macromolecules. The properties of the doubly modified samples were assessed using a wide variety of tests. Both the hydrophobic character and the density increased considerably, suggesting improved lifetime and extended domains of application.
Soda lignin precipitated from black liquor of Stipa tenacissima L. cooking was converted into pol... more Soda lignin precipitated from black liquor of Stipa tenacissima L. cooking was converted into polyols by a chain extension reaction with propylene oxide (PO). It was oxypropylated in a batch reactor in the presence of potassium hydroxide (KOH) as a catalyst. The reaction conditions were optimized by modifying the lignin/propylene oxide ratio [L/PO (w/v)], the temperature and the catalyst content. L/PO ratios of 20/80, 30/70 and 40/60 and catalyst contents from 3% to 5% were used. The temperature of the reaction was varied from 120 to 140 °C. The ensuing polyols were characterized by FTIR, H-NMR spectroscopy and size exclusion chromatography. Also, their viscosity and hydroxyl index were determined. A decrease in the molecular weight was observed after the oxypropylation reaction, which was explained by lignin depolymerisation. The viscosity and the hydroxyl index of the polyols ranged from 0.48 to 4.2 Pa.s and 150 to 375, depending on the lignin/PO ratio. Rigid polyurethane foam (RP...
ABSTRACT Commercial oil-proof papers containing new family of fluorochemicals were characterized ... more ABSTRACT Commercial oil-proof papers containing new family of fluorochemicals were characterized in terms of surface and barrier properties and printability. XPS analyses demonstrated that the fluorochemicals added to these papers had shorter perfluoroalkyl chains, compared to those used few decades ago. Contact angle measurements were performed and the obtained data were processed according to Owens–Wendt–Rabel–Kaelble (OWRK) approach, in order to calculate the surface energy of the investigated samples. This set of experiments revealed that the values of the surface energy of the non-coated surfaces of oil-proof papers were low enough (i.e. about 5 mJ/m2) to repel both water and oil. The surface energy of the coated sides was, instead, close to that of classical organic surfaces (i.e. around 30 mJ/m2), which predicts their potentially good printability. In fact, microcontour test was performed as the basic test for evaluating printability of oil-proof papers and showed that ink pigment retention was not significantly influenced by the level of barrier to oil. However, the surface roughness was found to play a key role in such properties.
La synthese et la caracterisation (ir, rmn #1h et #1#3c, dsc, atg, spectrometrie de masse et tono... more La synthese et la caracterisation (ir, rmn #1h et #1#3c, dsc, atg, spectrometrie de masse et tonometrie) de mono- et diurethanes furaniques obtenus par condensation d'un di- ou monoalcool avec un di- ou monoisocyanate ont ete etudiees. Il apparait que l'atome d'hydrogene en position c5 du noyau furanique n'intervient pas lors de cette reaction de condensation. Une grande gamme de structures a ete exploree quant a la nature et la position des substituants tant au niveau des alcools qu'au niveau des isocyanates. Une etude cinetique realisee dans un but comparatif, avec ces memes produits, a permis de situer la reactivite des composes furaniques par rapport a ses homologues des series aliphatique et aromatique. Il s'est avere que les isocyanates de la serie furanique sont plus reactifs que ceux des autres series, alors que les alcools furaniques ont une reactivite semblable aux alcools benzyliques. Les alcools aliphatiques sont nettement plus reactifs. Une etude...
Chitin nanocrystals (ChNCs) and chitin nanofibers (ChNFs) are nanomaterials with great innovative... more Chitin nanocrystals (ChNCs) and chitin nanofibers (ChNFs) are nanomaterials with great innovative potential for sustainable applications in academic and industrial fields. The research related to their isolation and production, characterization, and utilization is still new. The aim of this study is to investigate the effects of the production process on the morphology and properties of ChNFs and ChNCs produced from the same source of chitin. ChNCs were prepared by acid hydrolysis of commercial shrimp shell α-chitin, and ChNFs were prepared by mechanical defibrillation using closed loop supermass colloidal grinding. Differences in their shape, size, and crystallinity were observed. ChNFs were observed to have higher aspect ratio, higher viscosity, and better thermal stability than ChNCs. Although the ChNC casting film had a higher degree of transparency, it had lower mechanical properties than ChNF film. In addition, the capacities of each nanomaterial for producing Pickering emulsi...
The invention relates to a method for marking paper, particularly cigarette paper, including the ... more The invention relates to a method for marking paper, particularly cigarette paper, including the following steps: forming an iridescent cellulose nanocrystal film from cellulose nanoparticles, dry-grinding the film into grains, incorporating the grains to serve as pigments in an aq. mixt. contg. a binder, coating the paper with the aq. mixt., and drying; wherein the step of forming the film includes three main sub-steps: manufg. cellulose nanocrystals (CNC), placing same in suspension and forming a film; and wherein, during the sub-step of manufg. cellulose nanocrystals (CNC), cellulose nanoparticles, having an elongate rod-like morphol., a form factor of 20 to 70, preferably 40 to 60, and a polydispersity index (PDI) of less than 0.1 are used as a starting material. [on SciFinder(R)]
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