References of "Jérôme, Christine"
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See detailPolymers bearing pendant catechols for organic electrode-active materials in lithium-ion batteries
Patil, Nagaraj ULg; Cordella, Daniela ULg; Aqil, Abdelhafid ULg et al

Conference (2016, May 23)

Herein, we describe the synthesis and organometallic-mediated radical polymerization of 1-vinyl-3-alkylimidazolium-type monomers bearing pendant catechols in its protected version, using a presynthesized ... [more ▼]

Herein, we describe the synthesis and organometallic-mediated radical polymerization of 1-vinyl-3-alkylimidazolium-type monomers bearing pendant catechols in its protected version, using a presynthesized alkyl‒cobalt(III) complex as monocomponent initiator/mediating agent in a controlled fashion. A neat post-polymerization deprotection, followed by facile anion exchange reactions afforded a novel multi-functional poly(ionic liquids)-bearing free catechol functionalities. Prototype Lithium-ion battery, consisting a binder- and current collector-free electroactive polymer-supported buckypaper as the composite cathode, delivered an impressive specific capacity in the range of 199–230 mA h g‒1, relatively at high discharge potential = 3.2–3.4 V (vs Li/Li+), as calculated from CV and galvanostatic charge-discharge experiments. The superior electrochemical performance of the composite cathode consisting of PIL-catechols active-material, in comparison with poly(dopaminde acrylamide) is ascribed to the intrinsic Li-ion conductivity and enhanced surface activity of the imidazolium backbone with TFSI counteranion, compared to the acrylamide backbone. [less ▲]

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See detailFe2O3 nanoparticle-functionalized N-doped carbon with interconnected, hierarchical porous structures as high-performance electrode for lithium ion batteries
Alkarmo, Walid ULg; Ouhib, Farid ULg; Aqil, Abdelhafid ULg et al

Poster (2016, May 23)

Thanks to their fascinating physical properties such as high surface area, multidimensional electron transport pathways and good mechanical strength, three dimensionally (3D) interconnected carbon porous ... [more ▼]

Thanks to their fascinating physical properties such as high surface area, multidimensional electron transport pathways and good mechanical strength, three dimensionally (3D) interconnected carbon porous frameworks have emerged as attractive materials for various electrochemical energy storage/conversion devices, including Li-ion batteries (LIBs), Li−O2 batteries, Li−S batteries, supercapacitors, and fuel cells. A hierarchically structured macro- and mesoporous N-doped carbon with dispersed Fe2O3 nanoparticles (NDC@Fe2O3) is prepared by thermal treatment of a novel composite composed by PMMA particles decorated by graphene oxide (GO), PPy and iron salts. The NDC@Fe2O3 composite exhibited high surface area with a hierarchical pores structure. Integrated as a lithium ion battery anode, NDC@Fe2O3 exhibited high reversible capacity of 930 mA h/g over 200 cycles. The combination of Fe2O3 nanoparticles with porous carbon to form hybrid anode has been an efficient way to maintain the electronic integrity of the whole electrode since the carbon acts as a buffer layer to accommodate the volume variation and to provide multidimensional electron transport pathways during the charge/discharge process. [less ▲]

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See detailTuning morphology and surface properties of emulsion-templated porous polymers by controlled radical polymerization
Mathieu, Kevin ULg; Jérôme, Christine ULg; Debuigne, Antoine ULg

Poster (2016, May 23)

Macroporous polymer monoliths with interconnected structures have attracted considerable interests in the last decades and sustain many applications in the fields of supported catalysis, chromatography ... [more ▼]

Macroporous polymer monoliths with interconnected structures have attracted considerable interests in the last decades and sustain many applications in the fields of supported catalysis, chromatography, microfluidic, water purification, membrane separation, tissue engineering, to name but a few. A very popular and straightforward synthetic approach for such open-cell polymers is the High Internal Phase Emulsion (HIPE) polymerization method. The latter consists in three steps: (i) stabilization of an emulsion in which an internal phase with a volume fraction higher than 74% is dispersed within a minor continuous phase containing a polymer network precursor, (ii) curing of the polymer phase by polymerization or crosslinking reactions, (iii) removal of the internal phase to release the porosity. The surface properties and morphology of the polyHIPEs are important features that must be controlled and adjusted for each applications. In this context, we prepared by controlled radical polymerization a series of well-defined amphiphilic copolymers having different hydrophilic-lipophilic balance (HLB) and chain-ends, used it as stabilizers for the emulsion-templated polymerizations and demonstrated the crucial effect of the structure of the macromolecular surfactant on the morphology of the polyHIPEs. Finally, the physical and chemical anchoring of the macromolecular surfactants at the surface pores were also considered for tuning the surface properties of the porous monoliths. [less ▲]

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See detailSynthesis of CO2-sourced hydrogels by using the non-isocyanate polyurethane (NIPU) chemistry
Gennen, Sandro ULg; Grignard, Bruno ULg; Thomassin, Jean-Michel ULg et al

Poster (2016, May 23)

Polyurethane (PUs) is one of the most important polymers and finds applications as elastomers, coatings, adhesives and sealants for automotive or construction. PU is also a material of choice in the ... [more ▼]

Polyurethane (PUs) is one of the most important polymers and finds applications as elastomers, coatings, adhesives and sealants for automotive or construction. PU is also a material of choice in the biomedical domain due to its good biocompatibility, biodegradation and mechanical properties. Especially, PUs hydrogels have been developed in the last years for biomedical applications such as soft contact lenses, wound dressing, drug delivery systems and scaffolds for tissue engineering. Traditionally, PUs are synthesized by a step-growth polymerization between diols and diisocyanates. Because of toxicity issues and a possible interdiction of isocyanates, we focused on developing new PU hydrogels using a non-isocyanate route (Figure 1). The polyurethanes formed by this route are called NIPU (for Non-Isocyanate PolyUrethane). Firstly, chemically cross-linked NIPU gels were synthesized by solvent-free polycondensation between a hydrophilic CO2-sourced polyethyleneglycol bi-cyclic carbonate and a diamine in the presence of a crosslinker. Then, NIPU gels were swelled in water till water equilibrium before characterization of their mechanical properties by compression tests. The influence of the cross-linking ratios (diamine/crosslinker ratio) and diamine structure on the swelling and the compression properties were studied. To reinforce the compression properties of NIPU hydrogel (increase in stress at break, strain at break and compression modulus), a nanofiller was dispersed in the cyclic carbonate/diamine/crosslinker formulation prior to polymerization. For the first time, nanocomposite NIPU hydrogels with high water contents (up to 80%) and good compression properties have been prepared by using low clay content. [less ▲]

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See detailPolyphosphoester containing amphiphilic block copolymers as drug nanocarriers
Yilmaz-Ergül, Zeynep ULg; Vanslambrouck, Stéphanie; Thiry, Justine ULg et al

Poster (2016, May 23)

The design of drug delivery systems (DDS) often requires biodegradable and biocompatible materials that allow safe retention and controlled release of the drug. In this respect, poly(ethylene oxide)-b ... [more ▼]

The design of drug delivery systems (DDS) often requires biodegradable and biocompatible materials that allow safe retention and controlled release of the drug. In this respect, poly(ethylene oxide)-b-polyphosphoester amphiphilic block copolymers are known to self-assemble into polymer micelles when placed in water are appropriate drug carriers. In this work, an unsaturated alkene side-chain was introduced on the cyclic phosphate monomer according to a one-step reaction followed by its organocatalyzed polymerization initiated by a poly(ethylene oxide) macroinitiator. After self-assembly into water, the micelles were cross-linked by UV irradiation. Then, these cross-linked micelles have been loaded by doxorubicin, which is a drug to use in cancer therapy. We observed that the doxorubicin loading increased with the number of double bonds on the polyphosphate block of non-cross-linked micelles. This diblock amphiphilic copolymer bearing pendant unsaturations appears thus particularly promising candidate to build micellar drug delivery systems for intravenous injection. [less ▲]

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See detailChitosan-based nanofibers mats for tissue engineering
Aqil, Abdelhafid ULg; Croisier, Florence ULg; Colige, Alain ULg et al

Conference (2016, May)

Polymer hydrogels resemble the natural living tissue due to their high water content and soft consistency. They find many applications in the design and production of contact and intraocular lenses ... [more ▼]

Polymer hydrogels resemble the natural living tissue due to their high water content and soft consistency. They find many applications in the design and production of contact and intraocular lenses, biosensors membranes, matrices for repairing and regenerating a wide diversity of tissues and organs. Polysaccharides such as chitosan and hyaluronic acid based hydrogels have shown a great potential for biomedical and pharmaceutical applications, on account of their remarkable compatibility with physiological medium. Besides, it is degraded in a physiological environment into non-toxic products, which make them outstanding candidates for short- to medium-term applications, especially for tissue engineering. In this respect, the preparation of nanometric fibers mats based on this polysaccharide are highly interesting as such structure mimics the one of skin extracellular matrix. Such nanofibrous materials can be prepared by electrospinning (Figure 1). This technique uses a high voltage to create an electrically charged jet of polymer solution to obtain polymer fibers ranging from nanometers to a few microns in diameter. We thus have investigated strategies allowing to generate chitosan based nanofiber mats exhibiting a mechanical resistance strong enough to be easily handled while keeping the peculiar features of chitosan hydrogels favoring the interaction with cells and soft tissues to provide efficient tissue reconstruction. In a first strategy, polysaccharide-based nanofibers with a multilayered structure were prepared by combining electrospinning (ESP) and layer-by-layer (LBL) deposition techniques. Elastic nanofibers bearing charges at their surface were firstly prepared by electrospinning poly(ε-caprolactone) (PCL) with a polyelectrolyte precursor. After activation by adjusting the pH, the layer-by-layer deposition of chitosan and hyaluronic acid, can be used to coat the electrospun fibers. A multilayered structure is then achieved by alternating the deposition of the positively charged chitosan with the deposition of a negatively charged polyelectrolyte. These novel polysaccharide-coated PCL fiber mats remarkably combine the mechanical resistance typical of the core material (PCL) – particularly in the hydrated state –, with the surface properties of chitosan. Besides, crosslinked nanofibrous mats of chitosan and polyethylene oxide blends, were successfully prepared via electrospinning technique followed by heat mediated chemical crosslinking. This chemical cross-linking allows adjusting the mechanical resistance of the mats while preserving their biocompatibility. In both cases, the control of the nanofiber structure offered by the electrospinning technology, makes the developed processes very promising to precisely design biomaterials for tissue engineering. Preliminary cell culture tests corroborate the potential use of such systems in wound healing applications. [less ▲]

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See detailCyclic and oligo-carbonates by organocatalytic coupling of CO2 with epoxides or oxetanes
Alves, Margot ULg; Grignard, Bruno ULg; Boyaval, Amélie ULg et al

Conference (2016, April 20)

Valorising CO2 as a renewable C1 feedstock for producing added value building blocks is the scope of many academic and industrial researches. Carbon dioxide is a thermodynamically and kinetically stable ... [more ▼]

Valorising CO2 as a renewable C1 feedstock for producing added value building blocks is the scope of many academic and industrial researches. Carbon dioxide is a thermodynamically and kinetically stable molecule that can be converted into five and six membered cyclic carbonates by coupling with epoxides or oxetanes, respectively, using appropriate catalysts. Although transition metal catalysts are efficient under atmospheric pressure and ambient temperature, most of them are poorly selective, sensitive to hydrolysis and/or oxidation and/or toxic whereas less/non-toxic and eco-friendly organocatalysts such as ionic liquids and halide salts are generally only efficient at very high temperature and pressure favouring their thermal degradation. To overcome these limitations, we developed a new highly efficient bicomponent homogeneous organocatalyst composed of an ammonium salt as the catalyst and fluorinated single or double hydrogen bond donor activators. Through online FTIR kinetic studies, we demonstrated that this new organocatalyst showed unexpected catalytic activity for the fast and selective addition of CO2 onto epoxides under solvent-free and mild experimental conditions. The use of this dual catalyst was then extended to the coupling of CO2 with less reactive oxetanes to produce hydroxyl telechelic oligocarbonates. In the first part of this talk, based on kinetics of reactions followed by online FTIR under pressure, we will describe the reaction conditions required for the organocatalytic coupling of CO2 with epoxides and oxetanes. In the second part, the mechanism of the reaction will be approached and discussed based on DFT calculations. Finally, we will compare and discuss the efficiency of various organocatalytic systems for this type of reaction. [less ▲]

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See detailDirect one-pot synthesis of poly(ionic liquid) nanogels by cobalt-mediated radical cross-linking copolymerization in organic or aqueous media
Weiss-Maurin, Mathilde ULg; Cordella, Daniela ULg; Jérôme, Christine ULg et al

in Polymer Chemistry (2016), 7(14), 2521-2530

Nanogels of controlled kinetic chain length were synthesized by cobalt-mediated radical cross-linking copolymerization (CMRccP) involving a vinyl monomer and a divinyl cross-linker. This strategy was ... [more ▼]

Nanogels of controlled kinetic chain length were synthesized by cobalt-mediated radical cross-linking copolymerization (CMRccP) involving a vinyl monomer and a divinyl cross-linker. This strategy was first validated to achieve neutral poly(vinyl acetate) nanogels by CMRccP of vinyl acetate and divinyl adipate as cross-linker, at 40 °C, in presence of an alkyl- cobalt(III) serving both as initiator and controlling agent, using ethyl acetate as solvent. Poly(ionic liquid) nanogels were then directly obtained by CMRccP of N-vinyl-3-ethyl imidazolium bromide, in presence of 1,13-divinyl-3-decyl diimidazolium bromide as cross-linker. CMRccP experiments could be conducted either in organic solvent using dimethyl formamide or, more interestingly, in aqueous solution, demonstrating the robustness and the versatility of this one-step process. Chain extensions of PILs nanogels were also carried out in water, forming core-shell structures, thus opening new avenues in the design of functional nanogels. [less ▲]

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See detailCO2-blown microcellular non-isocyanate polyurethane (NIPU) foams: from bio- and CO2-sourced monomers to potentially thermal insulating materials
Grignard, Bruno ULg; Thomassin, Jean-Michel ULg; Gennen, Sandro ULg et al

in Green Chemistry (2016), 18(7), 2206-2215

Bio- and CO2-sourced non-isocyanate polyurethane (NIPU) microcellular foams were prepared using supercritical carbon dioxide (scCO2) foaming technology. These low-density foams offer low thermal ... [more ▼]

Bio- and CO2-sourced non-isocyanate polyurethane (NIPU) microcellular foams were prepared using supercritical carbon dioxide (scCO2) foaming technology. These low-density foams offer low thermal conductivity and have an impressive potential for use in insulating materials. They constitute attractive alternatives to conventional polyurethane foams. We investigated CO2’s ability to synthesize the cyclic carbonates that are used in the preparation of NIPU by melt step-growth polymerization with a bio-sourced amino-telechelic oligoamide and for NIPU foaming. Our study shows that CO2 is not only sequestered in the material for long-term application, but is also valorized as a blowing agent in the production of NIPU foams. Such foams will contribute to energy conservation and savings by reducing CO2 emissions. [less ▲]

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See detailHot Melt Extrusion as a New Method to Form Inclusion Complexes with Cyclodextrins
Thiry, Justine ULg; Krier, Fabrice; Ratwatte, Shenelka et al

Conference (2016, April 06)

Detailed reference viewed: 33 (3 ULg)
See detailCO2-based sustainable polymers: from CO2-sourced monomers to low CO2 emission foamed materials
Grignard, Bruno ULg; Gennen, Sandro ULg; Alves, Margot ULg et al

Conference (2016, April)

Due to concerns about the climate change combined with the decrease of fossil resources, the use of CO2 as a C1 feedstock for producing added value chemicals and materials has become a huge challenge in ... [more ▼]

Due to concerns about the climate change combined with the decrease of fossil resources, the use of CO2 as a C1 feedstock for producing added value chemicals and materials has become a huge challenge in academic laboratories and in industry. The coupling of CO2 with epoxide has emerged as one of the most promising way to convert CO2 into cyclic carbonates finding application as green solvents or electrolyte for batteries. Interestingly, these cyclic carbonates can also be valorised as monomers to produce new non-isocyanate polyurethanes by step-growth polymerization with amines. Polyurethane (PU) is one of the most important polymers in our everyday life with numerous applications such as thermosets, thermoplastics, elastomers, adhesives, sealants, coatings, rigid and flexible foams for wellness or acoustic and/or thermal insulation. In this talk, we will discuss the preparation of all green bio- and CO2-sourced non-isocyanate polyurethane (NIPU) microcellular foams with thermal insulation properties by using an eco-efficient process based on the supercritical carbon dioxide (scCO2) foaming technology. This talk will be divided in three sections: The synthesis of CO2-sourced cyclic carbonates by coupling CO2 with epoxides using a new highly-efficient bicomponent homogeneous organocatalyst combining the use of an ammonium salt as the catalyst and a fluorinated hydrogen bond donor activator that allows the fast and solvent-free coupling of CO2 with (biosourced) epoxides under mild experimental conditions. The synthesis of (bio- and) CO2-sourced isocyanates-free PUs by melt step-growth copolymerization, eliminating the toxicological issues associated to the conventional synthesis of polyurethanes from diols and isocyanates. The foaming of NIPUs by exploiting the scCO2 foaming technology. By finely choosing the appropriate CO2 impregnation and foaming conditions, thermally insulating CO2-blown microcellular NIPUs foams were produced. [less ▲]

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See detailNon-isocyanate polyurethanes from carbonated soybean oil Using monomeric or oligomeric diamines To achieve thermosets or thermoplastics
Poussard, Loïc; Mariage, J.; Grignard, Bruno ULg et al

in Macromolecules (2016), 49(6), 2162-2171

Fully bio- and CO2-sourced non-isocyanate polyurethanes (NIPUs) were synthesized by reaction of carbonated soybean oil (CSBO) either with biobased short diamines or amino-telechelic oligoamides derived ... [more ▼]

Fully bio- and CO2-sourced non-isocyanate polyurethanes (NIPUs) were synthesized by reaction of carbonated soybean oil (CSBO) either with biobased short diamines or amino-telechelic oligoamides derived from fatty acids to achieve respectively thermoset or thermoplastic NIPUs. Biobased carbonated vegetable oils were first obtained by metal-free coupling reactions of CO2 with epoxidized soybean oils under supercritical conditions (120 °C, 100 bar) before complete characterization by FTIR, 1H NMR, and electrospray ionization mass spectroscopy (ESI-MS). In a second step, biobased NIPUs were produced by melt-blending of the so-produced cyclocarbonated oil with the biobased aminated derivatives. The thermal and mechanical properties of resulting polymers were found to be depending on the cyclocarbonated vegetable oil/amine ratio. More precisely, short diamines and CSBO led to the formation of cross-linked NIPUs, and the resulting tensile and thermal properties were poor. In contrast, elastomeric NIPUs derived from oligoamides and CSBO exhibited a better rigidity, an improved elongation at break (εr up to 400%), and a higher thermal stability (T95 wt% > 350 °C) than those of starting oligoamides. These results are impressive and highlight the potentiality of this environmental friendly approach to prepare renewable NIPU materials of high performances. [less ▲]

Detailed reference viewed: 92 (18 ULg)
See detailTheoretical study of the organocatalyzed synthesis of NIPUs
Alves, Margot ULg; Méreau, Raphaël; Grignard, Bruno ULg et al

Poster (2016, March)

Detailed reference viewed: 15 (3 ULg)
See detailCarbon dioxide and vegetable oil for the synthesis of bio-based polymer precursors, theoretical study of the organocatalyzed synthesis of non-isocyanate polyurethanes
Alves, Margot ULg; Jérôme, Christine ULg; Tassaing, Thierry

Conference (2016, March)

Non-isocyanate polyurethanes (NIPUs) represent a green alternative to the classical synthesis route of polyurethanes involving toxic isocyanates. This “greener” approach based upon renewable feedstocks ... [more ▼]

Non-isocyanate polyurethanes (NIPUs) represent a green alternative to the classical synthesis route of polyurethanes involving toxic isocyanates. This “greener” approach based upon renewable feedstocks and carbon dioxide consists in a two-step reaction. In a first step, carbonated vegetable oils are obtained using an appropriate catalyst by the chemical fixation of CO2 onto vegetable oils formerly epoxidized. Finally, the ring-opening polymerization (ROP) of the carbonated vegetable oil by a diamine provides hydroxy urethanes. In this las step, some organocatalysts have been recently proposed that allows achieving good conversion rates in particular in the case of aromatic diamines. However, the activation mechanism of these organocatalysts is not fully elucidated. In this context, the aim of the present project relies on the theoretical study of a model reaction using DFT calculations. Bicyclic guanidine based catalysts, 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) and 7-methyl-TBD (MTBD), were investigated as catalysts for the reaction between propylene carbonate and aliphatic or aromatic amines. The structural ability of TBD to simultaneously give and receive protons was highlighted by the detailed mechanism investigation. The bifunctional activity of TBD significantly reduces the Gibbs energy of the reaction and allows understanding its higher efficiency compared to its methyl counterpart (MTBD). [less ▲]

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See detailCobalt-mediated radical polymerization of vinyl acetate and acrylonitrile in supercritical carbon dioxide
Kermagoret; Chau, Ngoc Do Quyen; Grignard, Bruno ULg et al

in Macromolecular Rapid Communications (2016), 39(6), 539-544

Cobalt-mediated radical polymerization (CMRP) of vinyl acetate (VAc) is successfully achieved in supercritical carbon dioxide (scCO 2 ). CMRP of VAc is conducted using an alkyl-cobalt(III) adduct that is ... [more ▼]

Cobalt-mediated radical polymerization (CMRP) of vinyl acetate (VAc) is successfully achieved in supercritical carbon dioxide (scCO 2 ). CMRP of VAc is conducted using an alkyl-cobalt(III) adduct that is soluble in scCO2 . Kinetics studies coupled to visual observations of the polymerization medium highlight that the melt viscosity and PVAc molar mass ( Mn ) are key parameters that affect the CMRP in scCO2. It is noticed that CMRP is controlled for M n up to 10 000 g mol−1 , but loss of control is progressively observed for higher molar masses when PVAc precipitates in the polymerization medium. Low molar mass PVAc macroinitiator, prepared by CMRP in scCO2 , is then successfully used to initiate the acrylonitrile polymerization. PVAc-b-PAN block copolymer is collected as a free flowing powder at the end of the process although the dispersity of the copolymer increases with the reaction time. Although optimization is required to decrease the dispersity of the polymer formed, this CMRP process opens new perspectives for macromolecular engineering in scCO2 without the utilization of fluorinated comonomers or organic solvents. [less ▲]

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See detailRecyclable shape-memory materials based on photo- or thermo-reversible reactions
Defize, Thomas ULg; Riva, Raphaël ULg; Thomassin, Jean-Michel ULg et al

Poster (2016, February 16)

Shape-memory polymers (SMPs) are remarkable materials able to switch from a stressed deformed state (temporary shape) to their initial relaxed state (permanent shape) by the application of a stimulus ... [more ▼]

Shape-memory polymers (SMPs) are remarkable materials able to switch from a stressed deformed state (temporary shape) to their initial relaxed state (permanent shape) by the application of a stimulus, such as heat or light. Typically, the shape-memory property is generally observed for chemically or physically cross-linked polymers that exhibit an elastomeric behavior above a phase transition, e.g. glass or melting transition. As an example, cross-linked semi-crystalline poly(ε-caprolactone) (PCL) is widely studied for the development of SMPs. As most of SMPs are irreversibly cross-linked material, their reprocessing is impossible preventing any recycling. Thereby, reversible reactions, allowing the formation/cleavage of the network, raise tremendous interest for the development of new SMPs. Recently, we reported the preparation reversibly cross-linked PCL-based SMP using the Diels-Alder (DA) reaction between furan and maleimide end-groups of 4-arm star-shaped PCL, well-known to create reversible bonds. After implementation, this shape-memory material was demonstrated to be recyclable, and was characterized by excellent fixity and recovery before and after recycling experiments. However, the relatively low retro DA temperature of the furan-maleimide adducts led to an inelastic deformation during shape-memory tensile cycles. In order to get rid of this drawback, an alternative approach was investigated. The substitution of the DA reaction by a photo-reversible reaction, typically the photo-induced (2+2) cycloaddition of coumarins, was proposed to prepare cross-linked PCL matrix presenting one-way and two-way memory properties, since photolabile adducts are supposed to be stable during shape-memory tensile cycles. [less ▲]

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See detailSolubility and speciation of ketoprofen and aspirin in supercritical CO2 by infrared spectroscopy
Champeau, Mathilde; Thomassin, Jean-Michel ULg; Jérôme, Christine ULg et al

in Journal of Chemical & Engineering Data (2016), 61(2), 968-978

The solubility of ketoprofen and aspirin in subcritical and supercritical CO2 was measured using FTIR absorption spectroscopy in the large range of temperature of 298.2−353.2 K and pressure of 5−35 MPa ... [more ▼]

The solubility of ketoprofen and aspirin in subcritical and supercritical CO2 was measured using FTIR absorption spectroscopy in the large range of temperature of 298.2−353.2 K and pressure of 5−35 MPa. The evolution of the solubility of both active pharmaceutical ingredients (APIs) was fitted using the Chrastil’s equation. In addition, the speciation of both APIs in monomeric and dimeric forms was explored by analyzing the characteristic carbonyl stretching vibrations of the carboxylic acid functions assigned to the dimers and monomers, respectively. Moreover, the evolution of the dimerization constant K of the two drugs as a function of the temperature and the pressure of scCO2 has been reported. [less ▲]

Detailed reference viewed: 67 (7 ULg)