Publications Scientifiques
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Item Study of the interfacial adhesion between alfa fiber and synthetic resin in a new biocomposite material(Elsevier, 2022) Kadem, Sihem; Irinislimane, Ratiba; Belhaneche-Bensemra, NaimaThe Interfacial adhesion between fiber and resin has a strong influence on composite mechanical performance and thermal stability. Natural fibers like alfa have attracted a great interest to be used as reinforcement for polymer composites. In this work biocomposites were prepared from natural substances by bleinding alfa plants (Stipa tenacissima) as natural reinforce fibers and modified sunflower oil (Helianthus annuus) as synthetic resin. The application of alfa fibers as reinforcement for composites requires a strong adhesion between the fibre and the resin. In the present work, alfa fibers were added to the synthetic resin after alkaline treatment with 5% NaOH solution. Biocomposites were prepared by using treated and untreated alfa fibers and characterised in terms of tensile properties, thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The results showed a good interfacial adhesion between treated alfa fibers and the resin. On the other hand, a thermal improvement was observed for biocomposites with treated alfa fibersItem Application of Fourier Transform Infrared (FT-IR) Spectroscopy to the Study of the Modification of Epoxidized Sunflower Oil by Acrylation(Sage journals, 2012) Irinislimane, Ratiba; Belhaneche-Bensemra, NaimaCommercial sunflower oil was epoxidized at the laboratory-scale. The epoxidized sunflower oil (ESFO) was modified following the acrylation reaction. Modification was carried out simultaneously using acrylic acid (AA) and triethylamine (TEA). To optimize the reaction conditions, the effects of four temperatures (40, 60, 80, and 100 °C), the ESFO:AA (100:100) ratio, and 0.2% TEA were investigated. The rate of conversion was analyzed with both FT-IR and titration of the oxirane ring. After that, the temperature with the highest conversion was selected and used throughout for all modification reactions. Then, four ratios (100:100, 100:90, 100:80, and 100:75) of ESFO:AA were analyzed at four different concentrations of TEA (0.2, 0.3, 0.4, and 0.5%) to determine the best estimate for both the ESFO:AA ratio and the catalyst concentration. Conversion rate was analyzed using FT-IR spectroscopy by measuring the concentrations of ester, carbonyl, and alcohol groups. Moreover, oxirane***ring concentration was estimated using the titration method (with gentian violet as indicator) and FT-IR spectroscopy (epoxy ring absorptions at 1270 cm−1 and 877 cm−1). Based on conversion yield, the optimum ESFO:AA ratio corresponds to 100:80; the best temperature reaction was at 60 °C, and the best TEA concentration was 0.2%. The critical amounts of reactants needed to reach maximum conversion were established. The final acid value of the acrylated ESFO after washing (pH = 7) was 2.1 mg potassium hydroxide (KOH) g−1. All results show that FT-IR spectroscopy is a simple, low-cost, rapid method for investigating the kinetics of a reactionItem Properties Investigation of Epoxidized Sunflower Oil as Bioplasticizer for Poly (Lactic Acid)(Springer, 2021) Bouti, Mohamed; Irinislimane, Ratiba; Belhaneche-Bensemra, NaimaThis study aims to improve low intrinsic ductility of poly (lactic acid) (PLA) by using a novel bio-sourced plasticizer environmentally friendly and cost-effective and to get a fully biodegradable material with potential application in films manufacturing. For that purpose, commercial sunflower oil (SO) was epoxidized and epoxidized sunflower oil (ESO) was used as plasticizer for PLA. To investigate ESO potential as plasticizer for PLA, its plasticizing effect was compared with commercial epoxidized soya bean oil (ESBO). Bioblends based on PLA and epoxidized vegetable oils (EVO) as bioplasticizers were prepared. The plasticizers (ESO or ESBO) were respectively compounded with PLA at 10, 20, 30, and 40 wt%. Mechanical (tensile and Shore D hardness), thermal (differential scanning calorimetry (DSC), thermogravimetric analysis (TGA)) and morphological properties (optical microscopy and scanning electron microscopy (SEM)) were characterized. The results showed that the addition of ESO or ESBO to PLA decreased tensile strength and tensile modulus compared to neat PLA but increased elongation at break for which an optimum (9 %, 16 and 34 % for ESBO, ESO5.5 % and ESO6.5 % respectively) was reached at a content of 20 wt% of plasticizer. The structures of the obtained plasticized PLA were confirmed by FTIR spectroscopy. The thermal properties (DSC), such as glass transition temperature (Tg) and melting temperature (Tm) were slightly decreased by addition of plasticizer into PLA, indicating that plasticizer increases the chain mobility and SEM analysis proved successful modification on the PLA brittle morphology with addition of EVO. On the other hand, TGA results revealed increase in the thermal stability. Also the results showed the effect of the EVO weight and the epoxy content (O.O value) on the improvement of the properties of PLA. ESO6.5 % at 20wt% was an efficient plasticizer for PLAItem Modification of diss fibers for biocomposites based on recycled Low-Density polyethylene and polypropylene blends(Springer, 2019) Touati, Zohra; Boulahia, Hakima; Belhaneche-Bensemra, Naima; Massardier, ValérieThe aim of this work is the valorization of diss fibers with recycled and regenerated low-density polyethylene (rLDPE) for the development of biocomposites based on blends of rLDPE polypropylene (PP) and diss fibers. The diss fibers were characterized by laser granulometer and FTIR spectroscopy. Two PP/rLDPE blends of different compositions (50/50 and 75/25) were prepared. These polymer blends were reinforced by nano-Si particles and compatibilizers which were investigated using three compatibilizers: maleic anhydride functionalized ethylene copolymer rubber (MAC), maleic anhydride functionalized ethylene copolymer rubber/SiO2 (MAC/SiO2), and maleic anhydride functionalized ethylene copolymer rubber/SiO2/ionic liquid (MAC/SiO2/IL). The thermal properties of the blends were studied using differential scanning calorimetry and thermogravimetric analysis. Their crystallinity was investigated by X-ray diffraction and their morphology by scanning electron microscopy, while mechanical properties were evaluated by tensile testing. The best tensile properties were obtained for the PP/rLDPE (75/25) blend. A significant increase of the Young’s modulus, stress at break, and elongation at break was obtained with the three compatibilizers. MAC acted as a compatibilizer of both polymers, resulting in improved interfacial adhesion which increased tensile properties. Finally, the effect of diss fiber surface modification on the properties of PP/rLDPE blends was considered. The results showed a modification of tensile properties and a satisfactory interfacial adhesion between diss fibers and polymer blends. Furthermore, thermal stability was not significantly decreased by the addition of 5 wt% diss fibersItem Analysis and quantitative estimation of phenolic antioxidants in polypropylene packaging for fat products(Freund Publishing House, 2018) Baloul, Hakim; Belhaneche-Bensemra, Naima; Bernaldo De Quirós, Ana Rodriguez; Sendon, RaquelThe aim of this work was to study the interactions between polypropylene (PP) food packaging for fatty products (margarine) and food simulant. For this purpose, a simulant (olive oil) was used in two different temperatures (20°C and 40°C). The interaction phenomena were investigated according to the rate of mass variation of PP samples with time and by using Fourier transform infrared spectroscopy, scanning electron microscopy and high-performance liquid chromatography (HPLC). The results showed the presence of two phenomena – migration of additives and sorption of the simulant, with the phenomena more pronounced at 40°C. Furthermore, the HPLC analysis identified the presence of Irganox 1010 and Irgafos 168 as antioxydants and allowed to carry out a kinetic study of Irganox 1010 migration. The concentration of Irganox 1010 decreased from 13.35 to 4.76 mg/kg at a temperature of 40°C and to 5.85 mg/kg at a temperature of 20°C after 10 days of contact with olive oil. The Irgafos 168 migration could not be evaluated because it is very sensitive to oxidation.Item Optimisation of operatory conditions for synthesis of sunflower Oil biobased polyols using design of experiments and spectroscopic methods(Springer, 2021) Irinislimane, Ratiba; Belhaneche-Bensemra, NaimaTheipresentiworkistudiesitheisynthesisiofibiopolyolsibasedioniepoxidizedisunfowerioili(ESFO)iandiobtainediviaialcoholysisi reaction.iTheiringiopeningireactioniESFOi(withianioxiraneiindex:iO.O%iofi6.2%)iwasicarriediusingianialcoholisolutioniandi boronitrifuoridei(asicatalyst).iTheioperatoryiconditionsiofisynthesisiwereioptimizediusingiaidesigniofiexperimenti(DOE).i Alcoholicontent,icatalystipercentiasiwelliasitemperatureiwereivariediaccordingitoiaiJMPisoftwareimatrix.iReactioniconversioni wasifollowedibyideterminationiofitheidecreaseiofiepoxyiringiusingititrationimethodiasiwelliasianiincreaseiofitheihydrox‑ ideigroup.iTheisynthesizedipolyolsiwereicharacterizediusingiFourieritransformiinfraredispectroscopyiandiprotoninucleari magneticiresonance.iTheiresultsishowedithatioxiraneiringihasitotallyidisappearedi(inisomeiformulations)iwhichimeansifulli conversion.iTheifullifactorialidesigniisianiefcientimethodiforitestingitheie ectiofioperatoryiconditionsiespeciallyiinilimitingi theinumberiofisynthesisiexperimentsItem Elaboration and Characterization of Polyurethane Foams Based on Renewably Sourced Polyols(Spriger link, 2020) Kahlerras, Zineb; Irinislimane, Ratiba; Bruzaud, Stephane; Belhaneche-Bensemra, NaimaThe aim of this work is to prepare and characterize a series of bio-polyurethane foams (Bio-PUFs) based on renewably sourced polyols in order to increase their ecological potential, while maintaining their properties. Polyurethane foams (PUFs) were obtained using two sunflower based-polyols (SF-P1 and SF-P2) with different hydroxyl numbers synthesized through the acid-catalyzed ring-opening of epoxidized sunflower oil (ESFO) and subsequent partial reduction of the ethylenic linkages to give hydroxyl moieties. These SF-Ps were applied for replacement of petrochemical polyol Confort P0010 with a mass fraction of SF-P in the range of 40–100%. The resins were characterized by Fourier transform infrared (FTIR) spectroscopy. Their solution viscosity and thermal behavior were investigated. The obtained SF-Ps were reacted with diisocianates to yield PUFs at a fixed NCO index. Several experiments were conducted by varying the amounts of polyols, isocyanate, catalysts, and surfactants until acceptable foams were obtained. The structures of the obtained PUFs were confirmed by FTIR spectroscopy and scanning electron microscopy (SEM). The morphology, the apparent density, the thermal behavior (thermogravimetric analysis and differential scanning calorimetry), and the thermal conductivity of the PUFs were investigated. The study showed that it is possible to substitute petrochemical polyols by the addition of SF-P to achieve PUFs with desirable properties. It was found that the mixing of SF-Ps in formulations influences especially the thermal and morphological properties, and increases the end product renewable material content. The highest renewable material content showed SF-PUFs (reaching 76%) since the renewable material content in SF-P is high (~ 92%). As a result of the SF-Ps loading in the range of 40–100% the PUFs change from flexible to semi-flexible structures. Furthermore, they become denser and exhibit numerous cell shapes, such as semi-open cells and closed cellsItem Effects of calcium stearate as pro-oxidant agent on the natural aging of polypropylene(Freund Publishing House, 2018) Bensaad, Fatima; Belhaneche-Bensemra, NaimaItem Novel biocomposites based on sunflower oil and alfa fibers as renewable resources(Springer, 2018) Kadem, Sihem; Irinislimane, Ratiba; Belhaneche-Bensemra, NaimaItem Novel biocomposites based on sunflower oil and alfa fibers as renewable resources(Springer, 2018) Kadem, Sihem; Irinislimane, Ratiba; Belhaneche-Bensemra, Naima