Jean-François GerardInstitut National des Sciences Appliquées de Lyon | INSA Lyon
Jean-François Gerard
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424
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November 2016 - December 2017
Publications
Publications (424)
Land transport is a major contributor to global CO2 emissions (14%). To reduce its impact, vehicles powered by hydrogen (H2) are being marketed. However, these vehicles are 2 to 3 times more expensive than fossil fuel vehicles, and take too long time to be manufactured at mass production level. The time required to complete all the stages in manufa...
This research looks into how to make and describe non-lethal projectile supports out of high-density polyethylene (HDPE) nanocomposites that are strengthened with alumina. This innovative approach enhances the material's mechanical properties and usability in security applications, significantly advancing over traditional materials. By integrating...
This study explored polyurethane foams with open-cell structures, emphasizing their potential in shock absorption applications, particularly within quasi-static compression environments. By synthesizing cellular polyurethanes via the reaction of polyisocyanates with polyols, we produced foams with varying degrees of flexibility, rigidity, and semi-...
This work covered essential technological progress in all the aspects of polyurethane foam growth, including cell nucleation and stability. The work also included developing an understanding of controlling cell morphology, size, and shape and improving closed and open-cell content. This necessitated a grasp of the character of surfactant catalysts,...
This study focuses on the detailed characterization of modified polyurethane foams, emphasizing their quasi-static compression behaviour and microstructural properties, to evaluate their potential application in shock-absorbing systems. Through systematic synthesis, we produced various formulations of polyurethane foams. We subjected them to compre...
In this study, LIonomers families based on phosphonium ILs have been successfully developed. These LIonomers are designed from the combination of various phosphonium‐based ionic liquids (PhILs) with different counter anions including tetradecyl (trihexyl) phosphonium bis (2,4,4‐trimethylpentyl) phosphinate (P⁺TMP), tributyl (ethyl) phosphonium diet...
Poly(methylmethacrylate-co-methacrylic acid) (PMMA-co-MAA) polymers were prepared via cobalt-mediated free radical copolymerization and were characterized after synthesis. The synthesis led to a 98.5% conversion and a final ratio between the two units, MMA/MAA, was equal to 63:37 mol%. PMMA-co-MAA was then used as a matrix for cellulose-based nanoc...
Aircraft, automotive industries and the increasing numbers of wind turbine blade lead to a huge amount of carbon fiber reinforced polymers requiring to be recycled and/or reused in a closed loop supply chain or circularity of materials. Herein, we have designed and synthesized a tetra-epoxidized imidazolium ionic liquid (Tetra-IL) monomer containin...
EIT RawMaterials fosters collaboration between academia, industry, and research institutions. By funding our business, you become part of a collaborative ecosystem, gaining access to a network of experts, knowledge-sharing platforms, and potential partnership opportunities. We are committed to actively engaging with stakeholders and leveraging the...
An extrinsic self-healing mechanism based on microencapsulated healing agents represents an original way to produce self-healable thermosetting materials without modifying the structural architecture of the co-monomers. In this work, self-healing was achieved through poly(melamine-formaldehyde) (PMF) microcapsules containing a polymerizable diepoxi...
In this work, by combining maleic anhydride-grafted polypropylene (PPgMA) and three different ionic liquids (ILs), i.e., tributyl (ethyl) phosphonium diethyl phosphate (denoted P+DEP), 1-ethyl-3-methylimidazolium diethyl phosphate (denoted EMIM DEP), and 1-ethyl-3-methylimidazolium acetate (denoted EMIM Ac), new ionic PP/IL polymer materials are ge...
Based on the models already on the market, we have manufactured six types of nonlethal projectiles. We have made convex heads out of polyurethane foam (PUR) filled with mineral fillers like alumina (Al2O3) and montmorillonite (MMT). We chose a suitable holder for nonlethal projectiles. Also, we made a custom industrial model and used CAD modeling i...
Based on the models already on the market, we have manufactured six types of nonlethal projectiles. We have made convex heads out of polyurethane foam (PUR) filled with mineral fillers like alumina (Al2O3) and montmorillonite (MMT). We chose a suitable holder for nonlethal projectiles. Also, we made a custom industrial model and used CAD modeling i...
The coatings which are able to protect the metal from being corroded by the medium in their service life while are easy to be removed when the regular maintenances and refurbishment of the coatings are carried out are in high demand. However, the relevant researches are few. In this article, a novel hexagonal boron nitride/epoxy anti-corrosive coat...
The design and development of multifunctional epoxy thermosets have recently stimulated continuous research on new degradable epoxy monomers. Herein, tri- and tetra-epoxidized imidazolium monomers were rationally designed with cleavable ester groups and synthesized on a multigram scale (up to 100 g), yielding room-temperature ionic liquids. These m...
Processing structural or semi-structural thermoplastic-based composites is a promising solution to solve the environmental issues of the aeronautic industry. However, these composites must withstand high standard specification to ensure safety during transportation. For this reason, there is a real need to develop strong interactions between thermo...
Bio-based and (bio)degradable polymers constitute an important material innovation because they reduce the amount of waste materials inducing persistent microplastics and can offer similar benefits to conventional polymer materials. Poly(butylene succinate) and poly(lactic acid) blends exhibit interesting properties and can be possible alternatives...
In this work, a varied content of alfa fiber was used as reinforcement and epoxy resin as matrix material. In order to eliminate the amorphous part of the alfa fiber, the fibers are treated with 5% of sodium hydroxide solution and their weight fraction is varied between 10% and 30%. Dielectric and water characteristics of different content of untre...
The main objective of this research is to examine the effect of various fiber content and alkali treatment on the thermal and mechanical properties of alfa fiber reinforced epoxy‐amine matrix‐based composites. The fibers are treated with 5% of sodium hydroxide solution and their weight fraction is varied between 10% and 30%. The flexural test is ca...
Due to their outstanding properties such as high optical transparency, high electrical resistance, high thermal insulation, good thermo-mechanical properties, and dimensional stability, epoxy networks play a key role in the world of thermosetting polymers. In fact, they are widely used in Industry as adhesives, paints and coatings, electrical and e...
We aim to maintain as much control over the microstructure development during the manufacture of polyurethane foam with a specific density. As a result, the finished product contains the shock absorber’s required characteristics. That is why polyurethane foam loaded with zinc oxide and silica must sustain the cellular structure and strengthen it. F...
We aim to maintain as much control over the microstructure development during the manufacture of polyurethane foam with a specific density. As a result, the finished product contains the shock absorber’s required characteristics. That is why polyurethane foam loaded with zinc oxide and silica must sustain the cellular structure and strengthen it. F...
In this paper, different types of polyurethane foams (PUR) having various chemical compositions have been produced with a specific density to monitor the microstructure as much as possible. The foam may have a preferential orientation in the cell structure. The cellular polyurethane tends to have stubborn, typical cellular systems with strong overl...
Abstract: New epoxy-amine networks issue from epoxydized imidazolium ionic liquid monomers (ILMs) and isophorone diamine (IPD) were modified for the first time by incorporating unmodified trisilanol phenyl POSS® (POSS®Ph-triol) and two ionic liquid-modified POSS®Ph (IL-g-POSS®Ph)
having chloride (Cl−) and bis-trifluoromethanesulfonimidate (NTf2−) c...
Among the biopolymers available in the world, polylactic acid (PLA) is one of the highest biopolymers produced globally, thus, making it suitable for product commercialization. The effectiveness of natural fibre–reinforced PLA composite as an alternative material to substitute the non-renewable petroleum-based materials has been examined by researc...
Designing innovative multi-functional thermoset polymers represents a major challenge in materials science. In this work, two novel polyhedral imidazolium ionic liquid supported on oligomeric silsesquioxane nanocages having chloride (Cl⁻) and bistrifluoromethanesulfonimidate (NTf2⁻) counter anions have been synthesized. These ionic nano-objects wer...
In this paper, the synergistic use of polyetherimide (PEI) and a phosphonium-based ionic liquid (IL) as multifunctional agents in epoxy networks is evidenced. Indeed, such a combination leads to tailor both morphology and interphase and acts as polymerization initiator. The influence of the PEI content (5, 10, 15, and 20 phr) on the morphology and...
In this work, alfa fiber reinforced polyvinyl chloride (PVC) composites treated with PVC‐g‐MA (5%), used as a compatibilizer, are prepared using three processing techniques: calendering, Brabender, and injection molding. The morphology, the tensile and thermal properties of PVC/alfa composites with and without compatibilizer obtained through these...
Carbon nanotube (CNT)-reinforced nanocomposites represent a unique opportunity in terms of designing advanced materials with mechanical reinforcement and improvements in the electrical and thermal conductivities. However, the toxic effects of these composites on human health have been studied, and very soon, some regulations on CNTs and on composit...
In this study, a novel polymerizable ionic liquid monomer (ILM) based on a bis-imidazolium salt was firstly synthesized in order to substitute bisphenol A diglycidyl ether (DGEBA) as starting material, avoiding the use of highly toxic and carcinogenic bisphenol A and epichlorohydrin products. From such a new epoxy monomer, epoxy network was prepare...
An efficient access to Cycloaliphatic Epoxy-Functionalized Ionic Liquids (CEIL) containing one or two imidazolium units was described for the first time. Due to the flexibility/versatility of the reported methodology, the synthesis of tailor-made ionic cycloaliphatic epoxy monomers was performed on a multigram scale (up to 25 g) in order to design...
In this work, silica microcapsules containing phosphonium ionic liquid (IL), denoted SiO2@IL, were successfully synthesized for the first time using the one step sol-gel method in IL/H20 emulsion. The morphologies of the obtained micron-size microcapsules, including their diameter distribution, were characterized using dynamic light scattering (DLS...
The nitroxide-mediated polymerization (NMP) of isoprene (I) initiated by the poly(ethylene-stat-butylene)-(SG1)2 dialkoxyamine (PEB-(SG1)2) at 115 oC in 50 vol% pyridine led to cis-1,4-rich poly(isoprene)s (PIs), exhibiting Mn,GPC = 52-59K (PI equivalents) and Ð = 1.46-1.59. S-I-S triblock copolymers (S = styrene, Mn,GPC = 95-109K, Ð = 2.11-2.29, F...
Proton exchange membranes designed via reactive extrusion from the in situ generation of functional silica-like particles in a new poly(vinylidene fluoride-co-hexafluoropropylene (poly(VDF-co-HFP)) copolymer are presented. These sulfonic acid-functionalized polysiloxane-based fillers were synthesized via sol-gel chemistry from 3-mercaptopropyltri(e...
Biodegradable polymers concern an important topic for innovation in materials, as they are supposed to contribute to the reduction in the amount of waste materials, which lead to microplastics with similar properties as conventional polymer materials. Poly(butylene succinate) and poly(lactic acid) blends are polymers with interesting properties off...
The objective of our present work is the development of polyurethane foam and the improvement of its mechanical and physicochemical properties. To propose an ideal method for elaborating and characterization of high density and good quality polymeric foams with maximum efficiency with non-lethal projectiles
Interfacial adhesion in poly (methyl methacrylate) (PMMA)/glass fiber (GF) composites which are processed by in-situ polymerization of an acrylic reactive mixture, has been studied at both micro- and macro-scales. On one hand model systems were evaluated at microscale using the microbond test. On the other the 15° off-axis tensile test was used to...
This study focuses on volatility and processing issues which can be faced when handling acrylic syrups designed for adhesive or composite applications. These reactive mixtures which are mainly constituted of methyl methacrylate (MMA) and poly(methyl methacrylate) (PMMA) can yield thermoplastic matrices through radical polymerization. However, the r...
Here, ionic liquids (ILs) based on imidazolium and ammonium cations were used as modifying agents for poly(methyl methacrylate) (PMMA) by extrusion. The effects of the chemical nature of the cation and/or counter anion on the resulting properties of IL-modified PMMA blends were analyzed. It was found that the use of low amounts of ILs (2 wt.%) impr...
In this work, two polyhedral oligomeric silsesquioxane-supported imidazolium ionic liquid have been successfully synthesized and used as organic-inorganic hybrid nano-objects in order to design nanostructured epoxy-amine networks. In fact, two partially condensed POSS have been covalently grafted with an ionic liquid-functionalized silane. The ther...
β-Myrcene (My), a natural 1,3-diene, and isobornyl methacrylate (IBOMA), from partially bio-based raw materials sources, were copolymerized by nitroxide-mediated polymerization (NMP) in bulk using the SG1-based BlocBuilder™ alkoxyamine functionalized with an N-succinimidyl ester group, NHS-BlocBuilder, at T = 100 °C with initial IBOMA molar feed co...
In this work, new (multi)functional-dedicated polymer materials were designed and processed from the co-polymerization between novel imidazolium ionic liquid monomer (ILM) with con-ventional polyetheramine denoted Jeffamine D230. First, a facile and robust synthetic route was investigated in order to design polyfunctional imidazolium monomers beari...
This study focuses on the characterization of acrylic reactive mixtures designed for liquid composite molding (LCM) and yielding thermoplastic matrices for composite applications. Conversion degree, complex viscosity, and cure exothermicity are tracked during the radical polymerization. Results show that these systems suffer from Trommsdorff's effe...
The toughness of a high-performance thermosetting epoxy network can be greatly improved by generating polyether sulfone−based macro- to nano-scale morphologies. Two polyethersulfones (PES) which only differ by their chain-end nature have been successively investigated as potential tougheners of a high-Tg thermoset matrix based on a mixture of trifu...
In this paper, a convenient, straightforward, and large-scale transferable approach for the preparation of fluorine-free bioinspired superhydrophobic silica-filled photo-crosslinked polyurethane-acrylate (PUA) nanocomposite films is reported. The enrichment of the hydrophobic fumed silica at the film surface and especially its inherent dual scale d...
The ability of different microstructures from ionic liquids (ILs) governed by anions and cations has been a source of curiosity for composite systems. In this present study, the structural behavior of polyvinylidene fluoride (PVDF) mixed with phosphonium- and imidazolium-based ionic liquids (1 wt%) combined with different counter anions was investi...
Supercritical carbon dioxide (scCO2) was considered as an environmental friendly medium for grafting the surface of silica nanoparticles with a series of reactive imidazolium-based ionic liquids (IL), denoted as IL-silanes. The effects of the reaction conditions on the resulting IL-grafted layers on the silica surface were characterized from thermo...
In order to design multiscale and multifunctional composites, synergy between carbon nanotubes and conventional carbon fibers was investigated. Two routes were compared to introduce carbon nanotubes into epoxy-carbon fibers composites either grown onto ex-PAN carbon fibers or directly under the form of carbon nanotubes (CNT) fibers. The multiscale...
Bulk nitroxide-mediated polymerization (NMP) of β-myrcene (My)/glycidyl methacrylate (GMA) mixtures with varying GMA molar feed fraction (fGMA,0 = 0.10–0.91) was accomplished at 120 °C, initiated by SG1-based alkoxyamine bearing a N-succinimidyl ester group (NHS-BlocBuilder). Low dispersity My/GMA copolymers (Đ < 1.56) with slight number-average mo...
In this work, the development of new biobased epoxy networks using phosphonium-based ionic liquids combined with dicyanamide and phosphinate counteranions as initiators of epoxy prepolymers was compared with a biobased epoxy-amine system. Ionic liquids (ILs) displayed high reactivity toward cardanol-based epoxy prepolymers, and the obtained biobase...
Nitroxide-mediated polymerization (NMP) of β-myrcene (My) at 120 °C in bulk using unimolecular SG1-based succinimidyl ester-functionalized BlocBuilder (BB) alkoxyamine resulted in low dispersity (Đ = 1.1–1.4) poly(myrcene)s P(My)s with high SG1 chain-end fidelity. The polymerizations also showed the number-average molecular weights (Mn) increased a...
Covalently stabilized polymer assemblies are normally fabricated from the self-assembly of polymer chains followed by a crosslinking reaction. In this report, we show that a crosslinking-induced self-assembly approach, in which boronate crosslinking sites are formed by the condensation reaction between boronic and catechol groups, can organize poly...
This work deals with the use of two types of poly(2,6-dimethyl-1,4-phenylene ether) (PPE) having different molar masses as toughening agents of epoxy/ionic liquid networks where phosphonium ionic liquids (ILs) combined with phosphinate and phosphate counteranions were used as curing agents of the epoxy prepolymer. The effect of the chemical nature...
Thermally reversible Diels-Alder adducts formed between furan and maleimide groups have been introduced into the interphase of a carbon fiber-reinforced composite material to design a self-healable composite material. The influence of the content of furfuryl glycidyl ether, FGE, comonomer which acts as a furan donor close to the interface was inves...
The PeakForce QNM AFM mode was used to investigate the nanoscale mechanical properties of poly(butylene-adipate-co-terephthalate)/poly(lactic acid) (PBAT/PLA) blends successfully compatibilized with phosphonium-based ionic liquids (ILs). This novel AFM mode allowed identification of the phase structuration and also emphasized the effect of the ioni...
To obtain a novel polyhedral oligomeric silsesquioxane (POSS)-based nanomodifier, copolymerization of methacrylate-POSS (MA-POSS) and glycidyl MA (GMA) was carried out via reversible addition-fragmentation chain transfer process. The as-synthesized poly(glycidyl methacrylate) (PGMA)-b-P(MA-POSS) block copolymers (BCPs) were characterized by proton...
In this study, electrospun fiber scaffolds based on biodegradable and bioabsorbable polymers and showing a similar structure to that of extracellular matrix (ECM) present in the neural tissues were prepared. The effects of electrospun-based scaffolds processed from poly(lactic acid) (PLA)/poly(lactide-b-ethylene glycol-b-lactide) block copolymer (P...
Electrospun polymer piezoelectric fibers can be used in neural tissue engineering (NTE) to mimic the physical, biological, and material properties of the native extracellular matrix. In this work, we have developed scaffolds based on polymer fiber architectures for application in NTE. To study the role of such three-dimensional scaffolds, a rotatin...
Mechanical properties of a common SMC (Sheet Molding Compound) matrix constituted of a vinylester resin and a Low-Profile Additive (LPA) were compared to those of vinylester modified with core-shell rubber (CSR) particles. Valuable properties are brought by CSR, especially high impact strength, high fracture toughness with little loss in stiffness,...
In this work, tetraalkylphosphonium and dialkyl imidazolium ionic liquids have been studied as surfactant agents of layered silicates (montmorillonite, MMT). The influence of the chemical nature of the cations as well as the counteranions on the thermal behavior (TGA), on the structural analysis (XRD) and on the surface energies of organically modi...
The development of mobile haptics and multimodal designs has been strongly limited by the lack of enabling actuator technologies. This paper presents the properties of an electrostrive actuator technology for haptic feedback. By carefully tailoring material properties and actuator designing which can be integrating in devices, this technology shoul...
The present work is about the investigation of the fire behavior of epoxy networks designed for structural composite materials used in aeronautics. Two high-Tg, infusion-suitable epoxy systems were studied. A model system was based on tetraglycidyl(diaminodiphenyl)methane (TGDDM) as an epoxy prepolymer, and 4,4′ methylene bis(2,6-diethylaniline) (M...
A new way to synthesize epoxy networks was reported in this work using phosphonium based ionic liquids combined with phosphinate, carboxylate, and phosphate counteranions. The influence of the chemical nature of the anions was investigated on the polymerization kinetics of epoxy systems as well as the thermal and mechanical properties of epoxy–IL n...
In materials science, the unique properties of ionic liquids (ILs) are the focus of the academic and industrial research. They are commonly used as an alternative to conventional solvents in various areas such as electrochemistry, catalytic reactions, extraction processes, and metal removal in the field of nuclear wastes. The use of ILs in the fiel...
Acrylic matrix/fiber interfaces were investigated by considering microcomposites as models of fiber-based composites. The study was conducted considering various types of sized glass and carbon fibers. On one hand, the surface tension and dynamic contact angle measurements were used to quantify the wettability of the fibers by the acrylic matrices,...
Ionic liquids based on tetraalkylphosphonium cations with long alkyl chains have been used as new compatibilizing agents of biopolymer blends composed of poly(butylene-adipate-co-terephtalate) (PBAT) and poly(lactic acid) (PLA). In this study, the influence of the chemical nature of the counter anion on the morphologies as well as the thermal and m...
In this study, synthesis of thiol-functionalized silica/PVDF-HFP [poly(vinylidene fluoride-hexafluoropropylene)] nanocomposite materials was carried out by reactive extrusion through in situ sol-gel reactions of an alkoxysilane inorganic precursor solution composed of polydimethoxysiloxane (PDMOS) and mercaptopropyltriethoxysilane (MPTES). Successf...