References of "Thomassin, Jean-Michel"
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See detailFast and facile one-pot one-step preparation of non-isocyanate polyurethane hydrogels in water at room temperature
Bourguignon, Maxime ULiege; Thomassin, Jean-Michel ULiege; Grignard, Bruno ULiege et al

in ACS Sustainable Chemistry and Engineering (in press)

Since the discovery of polyurethanes (PU) by Otto Bayer in 1937, PU hydrogels are still commonly produced by the polyaddition of nasty and toxic polyisocyanates with polyols in organic solvents or in the ... [more ▼]

Since the discovery of polyurethanes (PU) by Otto Bayer in 1937, PU hydrogels are still commonly produced by the polyaddition of nasty and toxic polyisocyanates with polyols in organic solvents or in the bulk, followed by their swelling in water. Their direct one-pot one-step synthesis in water is not possible due to the fast hydrolysis of isocyanates. The attractive greener variant for PU that consists in the polyaddition of poly(5-membered cyclic carbonate)s with polyamines is also suffering for a similar drawback (the hydrolysis of the cyclic carbonates), but also for the low reactivity of the reagents at room temperature. Herein, we report the first synthesis of PU hydrogels by a non-isocyanate route in water at room temperature from easily accessible CO2-sourced 5-membered cyclic carbonates (5CCs) and a commercially available polyamine. We demonstrate that PU hydrogels are now formed with impressive short gel times (15-20 min) provided that the pH is adjusted in the 10.5-11.5 range in order to limit 5CCs hydrolysis. Hydrogels of good mechanical properties and high swelling ability are prepared in a facile one-pot process. The robustness of the process is also illustrated by dispersing clays (natural or synthetic) or a natural hydrosoluble polymer (gelatin) in the formulation. These additives do not perturb the polymerization and enable to modulate the mechanical properties of the hydrogel. This works opens enormous perspectives in the design of elusive PU-based materials in water from largely accessible 5- membered cyclic carbonates. [less ▲]

Detailed reference viewed: 19 (6 ULiège)
See detailSupercritical CO2 foaming of PCL covalent networks : taking benefit from the thermo-reversible Diels-Alder cycloaddition
Houbben, Maxime ULiege; Malherbe, Cédric ULiege; Thomassin, Jean-Michel ULiege et al

Poster (2019, May 27)

Foams are versatile materials encountered in our daily life for a wide variety of uses such as cushioning, thermal and acoustic insulation or medical applications. The combination of the mixed properties ... [more ▼]

Foams are versatile materials encountered in our daily life for a wide variety of uses such as cushioning, thermal and acoustic insulation or medical applications. The combination of the mixed properties between a continuous matrix and gas cells and the diversity of pore structures represent a powerful tool for the design of new materials. Among the different polymer foam fabrication processes, the use of supercritical CO2 has been one of the most investigated in the past decade. Nevertheless, the design of crosslinked polymer foams with high foaming ratio still remains a challenge. Various crosslinking processes mainly based on heating, irradiation with the addition of an external agent have been applied after foaming but remain difficult to perform due to mass transfer issues of the crosslinking agent. When crosslinking occurs before foaming, it dramatically limits the material expansion. In order to overcome these drawbacks, the present work aims taking advantage of the thermoreversible Diels-Alder cycloaddition to elaborate foams of poly(ε-caprolactone) (PCL) covalent networks. Based on this reaction, we considered to induce cross-linking after the foam expansion by playing on the thermal equilibrium of the thermoreversible Diels-Alder cycloaddition. Therefore, low molar mass star-shaped PCL end-capped by furan or maleimide were impregnated with CO2 under supercritical conditions and then foamed under appropriate control of the pressure and temperature. Annealing about 2h at 40°C allows Diels-Alder adducts to be formed and a stable PCL network keeping at least 80% of the expanded volume is obtained. The resulting foam possesses a much higher volume expansion than a pre-crosslinked sample foamed in the same conditions, thanks to the low crosslinking ratio during foaming. These foams exhibit also improved thermal stability thanks to its chemical crosslinking as compared to non-crosslinked PCL foams. Interestingly, these foams possess shape memory properties due to the semi-crystallinity of the PCL. Thermal stability and shape memory properties were evaluated by dynamic mechanical analysis in both tensile and compression testing with controlled force mode, stress and temperature ramps. [less ▲]

Detailed reference viewed: 24 (2 ULiège)
See detailEfficient moisture-sensitive shape-memory materials composed of supramolecular network of poly(ε-caprolactone) and poly(ethylene oxide)
Caprasse, Jérémie ULiege; Thomassin, Jean-Michel ULiege; Riva, Raphaël ULiege et al

Poster (2019, May 27)

Shape-memory polymers (SMPs) are remarkable stimuli-responsive materials able to switch from one stable macroscopic shape to another one, which can find application as smart medical devices. For this ... [more ▼]

Shape-memory polymers (SMPs) are remarkable stimuli-responsive materials able to switch from one stable macroscopic shape to another one, which can find application as smart medical devices. For this purpose, covalent crosslinked poly(ε-caprolactone) (PCL) is widely studied because it is biocompatible, degradable, exhibits efficient thermally triggered shape memory properties, i.e. high fixity of the temporary shape, high recovery of the permanent shape and has good mechanical properties. In this work, an hydrophilic component, i.e. poly(ethylene oxide), is introduced into PCL networks in order to impart an additional shape transition triggered by hydration of the material at constant temperature. The network of both materials is formed by reaction of the maleimide end-capped PCL stars with furan end-capped PEO stars. After melt-mixing and a post-curing of 48h, this material shows high crosslinking density as demonstrated by swelling behavior, good mechanical properties and excellent shape memory properties,. Moreover, moisture triggered shape transition is observed in addition to conventional thermal shape memory properties. [less ▲]

Detailed reference viewed: 16 (2 ULiège)
See detailSynthesis of supramolecular networks of poly(e-caprolactone) and poly(ethylene oxide) as moisture sensitive shape-memory materials
Caprasse, Jérémie ULiege; Thomassin, Jean-Michel ULiege; Riva, Raphaël ULiege et al

Poster (2019, May 23)

Shape-memory polymers (SMPs) are remarkable stimuli-responsive materials able to switch from one stable macroscopic shape to another one, which can find application as smart medical devices. For this ... [more ▼]

Shape-memory polymers (SMPs) are remarkable stimuli-responsive materials able to switch from one stable macroscopic shape to another one, which can find application as smart medical devices. For this purpose, the covalent crosslinked poly(ε-caprolactone) (PCL) is widely studied because it is biocompatible, degradable, exhibit efficient thermally triggered shape memory properties, i.e. exhibit high fixity of the temporary shape and high recovery of the permanent shape and has good mechanical properties. In this work, an hydrophilic component, i.e. poly(ethylene oxide), is introduced into PCL networks in order to impart an additional shape transition triggered by hydration of the material at constant temperature. The network of both materials is formed by reaction of the maleimide end-capped PCL stars with and furan end-capped PEO stars. This material exhibits high crosslinking density and excellent shape memory properties, after a post-curing of 48h. Moisture triggered shape transition is observed in addition to conventional thermal shape memory properties. [less ▲]

Detailed reference viewed: 21 (2 ULiège)
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See detailCO2-sourced polycarbonates as solid electrolytes for room temperature operation lithium battery
Ouhib, Farid; Meabe, Leire; Mahmoud, Abdelfattah ULiege et al

in Journal of Materials Chemistry A (2019), 7(16), 9844-9853

In the last years, polycarbonates have been identified as alternatives to poly(ethylene oxide) as polymer electrolytes for lithium battery applications. In this work, we show the design of CO2-sourced ... [more ▼]

In the last years, polycarbonates have been identified as alternatives to poly(ethylene oxide) as polymer electrolytes for lithium battery applications. In this work, we show the design of CO2-sourced polycarbonates for its use in a room temperature lithium battery. Novel functional polycarbonates alternating oxo-carbonate moieties and polyethylene oxide segments are synthesized by the facile room temperature (rt) organocatalyzed polyaddition of CO2-sourced bis(?-alkylidene carbonate)s (bis-?CCs) with polyethylene oxide diols. The effect of the polyethylene oxide molar mass on the ionic conductivity and on the thermal properties of the poly(oxo-carbonate)s is investigated. The best candidate shows a low glass temperature of -44°C and a high ionic conductivity of 3.75 * 10-5 S cm-1 at rt when loaded with 30 wt% bis(trifluoromethanesulfonyl)imide salt (LiTFSI) without any solvent. All solid semi-interpenetrated network polymer electrolyte (SIN-SPE) is then fabricated by UV-cross-linking of a mixture containing a specifically designed poly(oxo-carbonate) bearing methacrylate pendants, diethylene glycol diacrylate and the previously described poly(oxo-carbonate) containing LiTFSI. The resulting self-standing membrane exhibits a high oxidation stability up to 5 V (vs Li/Li+), an ionic conductivity of 1.1 * 10-5 S cm-1 at rt (10-4 S cm-1 at 60°C) and promising mechanical properties. Assembled in a half cell configuration with LiFePO4 (LFP) as cathode and lithium as anode, the all-solid cell delivers a discharge capacity of 161 mAh g-1 at 0.1C and 60°C, which is very close to the theoretical capacity of LFP (170 mAh g-1). Also, a stable reversible cycling capacity over 400 cycles with high coulombic efficiency of 99 % is noted at 1C. Similar results are obtained at rt provided that 10 wt% of tetraglyme as plastisizer were added to SIN-SPE. I. [less ▲]

Detailed reference viewed: 49 (21 ULiège)
See detailImplants for trapping glioblastoma cells
Haji Mansor, Muhammad; Najberg, Mathie; Thomassin, Jean-Michel ULiege et al

Conference (2019, March)

Detailed reference viewed: 18 (2 ULiège)
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See detailPhoto-cross-linkable coumarin-based poly(ϵ-caprolactone) for light-controlled design and reconfiguration of shape-memory polymer networks
Defize, Thomas; Thomassin, Jean-Michel ULiege; Ottevaere, Heidi et al

in Macromolecules (2019), 52(2), 444-456

Photochemically cross-linked shape-memory polymer (SMP) materials have been achieved by functionalizing chain-ends of star-shaped poly(ϵ-caprolactone) (PCL) with 7-hydroxypropoxy-4-methylcoumarin followed ... [more ▼]

Photochemically cross-linked shape-memory polymer (SMP) materials have been achieved by functionalizing chain-ends of star-shaped poly(ϵ-caprolactone) (PCL) with 7-hydroxypropoxy-4-methylcoumarin followed by photodimerization of these end-groups. The kinetics of the network formation in function of the photosensitizer concentration has been studied by swelling experiments and rheology. Thanks to the design of a dedicated homemade mold, highly reproducible irradiation conditions have been achieved allowing to study the network formation and properties, especially the shape-memory properties, in relation to the coumarin dimerization degree as determined by Raman spectroscopy. In optimized conditions, PCL-based SMP materials exhibiting high fixity and recovery have been achieved in remarkably short irradiation time, typically 5 min. In addition, the precise control of the network cross-link density with the irradiation time, so as the high stability of the formed networks toward temperature variations was also demonstrated allowing the fine-tuning of the network properties by the irradiation process. Finally, the reversible character of the coumarin dimerization under light irradiation of appropriate wavelength has been quantified by Raman spectroscopy. The dimer photocleavage allows the photoreconfiguration of the networks offering the ability to modify the "permanent" shape of the SMP material, while preserving the excellent shape-memory properties. © 2018 American Chemical Society. [less ▲]

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See detailPoly(ionic liquid)-derived N-doped carbons with hierarchical porosity for lithium- and sodium-ion batteries
Alkarmo, Walid ULiege; Ouhib, Farid ULiege; Aqil, Abdelhafid ULiege et al

in Macromolecular Rapid Communications (2019), 40(1), 1800545

The performance of lithium‐ and sodium‐ion batteries relies notably on the accessibility to carbon electrodes of controllable porous structure and chemical composition. This work reports a facile ... [more ▼]

The performance of lithium‐ and sodium‐ion batteries relies notably on the accessibility to carbon electrodes of controllable porous structure and chemical composition. This work reports a facile synthesis of well‐defined N‐doped porous carbons (NPCs) using a poly(ionic liquid) (PIL) as precursor, and graphene oxide (GO)‐stabilized poly(methyl methacrylate) (PMMA) nanoparticles as sacrificial template. The GO‐stabilized PMMA nanoparticles are first prepared and then decorated by a thin PIL coating before carbonization. The resulting NPCs reach a satisfactory specific surface area of up to 561 m2 g−1 and a hierarchically meso‐ and macroporous structure while keeping a nitrogen content of 2.6 wt%. Such NPCs deliver a high reversible charge/discharge capacity of 1013 mA h g−1 over 200 cycles at 0.4 A g−1 for lithium‐ion batteries, and show a good capacity of 204 mA h g−1 over 100 cycles at 0.1 A g−1 for sodium‐ion batteries. [less ▲]

Detailed reference viewed: 56 (14 ULiège)
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See detailIn situ photochemical crosslinking of hydrogel membrane for guided tissue regeneration
Chichiricco, Pauline Marie ULiege; Riva, Raphaël ULiege; Thomassin, Jean-Michel ULiege et al

in Dental Materials (2018), 34(12), 1769-1782

Periodontitis is an inflammatory disease that destroys the tooth-supporting attachment apparatus. Guided tissue regeneration (GTR) is a technique based on a bar- rier membrane designed to prevent wound ... [more ▼]

Periodontitis is an inflammatory disease that destroys the tooth-supporting attachment apparatus. Guided tissue regeneration (GTR) is a technique based on a bar- rier membrane designed to prevent wound space colonization by gingival cells. This study examined a new formulation composed of two polymers that could be photochemically cross-linked in situ into an interpenetrated polymer network (IPN) forming a hydrogel mem- brane. Methods. We synthetized and characterized silanized hydroxypropyl methylcellulose (Si- HPMC) for its cell barrier properties and methacrylated carboxymethyl chitosan (MA-CMCS) for its degradable backbone to use in IPN. Hydrogel membranes were cross-linked using riboflavin photoinitiator and a dentistry visible light lamp. The biomaterial’s physicochem- ical and mechanical properties were determined. Hydrogel membrane degradation was evaluated in lysozyme. Cytocompatibility was estimated by neutral red uptake. The cell bar- rier property was studied culturing human primary gingival fibroblasts or human gingival explants on membrane and analyzed with confocal microscopy and histological staining. Results. The IPN hydrogel membrane was obtained after 120 s of irradiation. The IPN showed a synergistic increase in Young moduli compared with the single networks. The CMCS addition in IPN allows a progressive weight loss compared to each polymer network. Cyto- compatibility was confirmed by neutral red assay. Human cell invasion was prevented by hydrogel membranes and histological sections revealed that the biomaterial exhibited a barrier effect in contact with soft gingival tissue. [less ▲]

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See detailCatechol containing polyhydroxyurethanes as high-performance coatings and adhesives
Panchireddy, Satyannarayana ULiege; Grignard, Bruno ULiege; Thomassin, Jean-Michel ULiege et al

in ACS Sustainable Chemistry and Engineering (2018), 6(11), 14936-14944

Green routes for the synthesis of high-performance isocyanate-free polyurethane coatings and adhesives are intensively searched for. In this article, we report a solvent- and isocyanate-free formulation ... [more ▼]

Green routes for the synthesis of high-performance isocyanate-free polyurethane coatings and adhesives are intensively searched for. In this article, we report a solvent- and isocyanate-free formulation for novel poly(hydroxyurethane) glues bearing strongly adherent catechol groups. These adhesives are prepared by the polyaddition of a CO2-sourced tricyclic carbonate, hexamethylene diamine, and a catecholamine (dopamine). The role of the catechol functions on the PHU curing and on the final PHU properties are investigated. Although the dopamine slows down the curing of the formulation, this catecholamine added at only 3.9 mol % impressively improves the mechanical and adhesion performances of PHU. The lap shear adhesion of our product surpasses those of PHU that do not contain the catechols. We also demonstrate that the catechol-bearing PHU glues are competing with the adhesion performances of commercial PU glues, at least when a thermal curing is implemented to overcome the low reactivity of cyclic carbonate with amines. The use of renewable feedstocks, the solvent-free process, the atom economy polyaddition reaction, and the absence of any toxic reagent benefit the sustainability of the final product. [less ▲]

Detailed reference viewed: 36 (4 ULiège)
See detailDesign of reprocessable poly(ε-caprolactone)-based shape-memory materials by reversible tad chemistry
Riva, Raphaël ULiege; Defize, Thomas; Alexandre, Michaël et al

Poster (2018, October 03)

Detailed reference viewed: 32 (5 ULiège)
See detailTargeting the SDF-1α/CXR4 signalling axis for the trapping of glioblastoma cells
Haji Mansor, Muhammad; Najberg, Mathie; Thomassin, Jean-Michel ULiege et al

Conference (2018, September 28)

Detailed reference viewed: 23 (2 ULiège)
See detailFunctionalized polymeric implants for trapping of glioblastoma cells
Haji Mansor, Muhammad; Najberg, Mathie; Thomassin, Jean-Michel ULiege et al

Poster (2018, September 09)

Detailed reference viewed: 25 (2 ULiège)
See detailSustainable poly(hydroxyurethane)s thermoset adhesives for affixing metals
Panchireddy, Satyannarayana ULiege; Grignard, Bruno ULiege; Thomassin, Jean-Michel ULiege et al

Poster (2018, June 20)

In the last five years, isocyanates-free polyhydroxyurethanes (PHUs), synthesized by step-growth polymerization between bis-cyclic carbonates and di- or poly-amines, have emerged as a novel class of ... [more ▼]

In the last five years, isocyanates-free polyhydroxyurethanes (PHUs), synthesized by step-growth polymerization between bis-cyclic carbonates and di- or poly-amines, have emerged as a novel class of polyurethanes (PUs). These PHUs find promising applications in flooring, paints, as thermoset materials or (thermal insulation) foams. PHUs can be also exploited advantageously for designing the next generation of high performance polyurethane adhesives. Thanks to the presence of pendant hydroxyl groups favoring the polymer/substrate interactions, the adhesion performances of PHUs may equal or even surpass the ones of conventional PUs. In this contribution, we focused on the design of novel reinforced bio- and CO2-based PHU thermosets adhesives with high shear adhesion strength for metal substrates (aluminum and stainless steel). The research included: The synthesis of a library of bi- or multifunctional 5-membered cyclic carbonates by coupling CO2 with (bio-based) epoxidized precursors using a novel home-made binary organocatalyst highly performant under very mild experimental conditions. The development of solvent-free reinforced PHU thermoset adhesives from various cyclic carbonate/amine/functional fillers formulations. For all formulations, curing kinetics was monitored by rheology to determine the gelation time and the thermo-mechanical and physico-chemical properties of PHUs were evaluated on free-standing films. The evaluation of the adhesives performances for metal sticking: The adhesion of (reinforced) PHUs onto Al-2024-T3 or stainless steel substrates was evaluated by standard cross-cut adhesion (5B) and MEK double rubber (>300) tests and shear adhesion strength (>16 MPa). [less ▲]

Detailed reference viewed: 23 (2 ULiège)
See detailSustainable poly(hydroxyurethane)s thermoset adhesives for affixing metals
Panchireddy, Satyannarayana ULiege; Grignard, Bruno ULiege; Thomassin, Jean-Michel ULiege et al

Conference (2018, June 18)

In the last 5 years, isocyanates-free polyhydroxyurethanes (PHUs), synthesized by step-growth polymerization between biscyclic carbonates and di- or poly-amines, have emerged as a novel class of ... [more ▼]

In the last 5 years, isocyanates-free polyhydroxyurethanes (PHUs), synthesized by step-growth polymerization between biscyclic carbonates and di- or poly-amines, have emerged as a novel class of polyurethanes (PUs). These PHUs find promising applications in flooring, paints, as thermoset materials or (thermal insulation) foams. PHUs can be also exploited advantageously for designing the next generation of high performance polyurethane adhesives. Thanks to the presence of pendant hydroxyl groups favouring the polymer/substrate interactions, the adhesion performances of PHUs may equal or even surpass the ones of conventional PUs. In this contribution, we focused on the design of novel reinforced bio- and CO2-based PHU thermosets adhesives with high shear adhesion strength for metal substrates (aluminium and stainless steel). [less ▲]

Detailed reference viewed: 14 (4 ULiège)
See detailFunctionalized polymeric implants for trapping of glioblastoma cells
Haji Mansor, Muhammad; Najberg, Mathie; Thomassin, Jean-Michel ULiege et al

Conference (2018, June 14)

Detailed reference viewed: 42 (8 ULiège)