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Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Propriétés et caractérisation, Properties and characterization, Propriétés des solutions et des gels, Solution and gel properties, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Pharmacologie. Traitements medicamenteux, Pharmacology. Drug treatments, Pharmacologie générale, General pharmacology, Technologie pharmaceutique. Industrie pharmaceutique, Pharmaceutical technology. Pharmaceutical industry, Amine polymère, Amine polymer, Amina polímero, Amine tertiaire, Tertiary amine, Amina terciaria, Cinétique, Kinetics, Cinética, Colorant organique, Organic dye, Colorante orgánico, Effet structure, Structure effect, Efecto estructura, Effet température, Temperature effect, Efecto temperatura, Etude expérimentale, Experimental study, Estudio experimental, Gel colloïdal, Colloidal gel, Gel coloidal, Gonflement, Swelling, Inflamiento, Libération, Release, Liberación, Méthacrylate polymère, Methacrylate polymer, Metacrilato polímero, Polymère vecteur, Control release polymer, Polímero vector, Polymérisation radicalaire, Free radical polymerization, Polimerización radicalar, Polyélectrolyte, Polyelectrolyte, Polielectrolito, Préparation, Preparation, Preparación, Rhodamine, Rodamina, Triazole dérivé polymère, Triazole derivative polymer, Triazol derivado polímero, Vecteur médicament, Drug carrier, Vector medicamento, pH, Effet densité réticulation, Interaction pi pi, Polymère sensible stimuli, DMAEMA, anticancer, hydrogels, sustained release, and triazole

The purpose of this study is to develop novel triazole-containing hydrogels (TGs) as drug carrier and to investigate the sustained drug release accomplished by their time-dependent swelling behavior. The synthetic pathway of TGs includes: (1) DCC-coupling on hydroxyethyl methacrylate (HEMA) to prepare HEMA-alkyne (HA), (2) click-coupling to prepare a triazole-ring-containing monomer (TM), and (3) the synthesis of a series of TGs. The aggregation between triazole rings is found to be responsible for drug release controllability. Rhodamine 6G is studied as a model anticancer drug for release experiments. The effects of pH and temperature on the properties of sustained drug release are also studied.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères d'origine naturelle, Natural polymers, Divers, Miscellaneous, Polymères organiques, Organic polymers, Propriétés et caractérisation, Properties and characterization, Propriétés des solutions et des gels, Solution and gel properties, Article synthèse, Review, Artículo síntesis, Cinétique, Kinetics, Cinética, Densité charge, Charge density, Densidad carga, Diffusion lumière, Light scattering, Difusión luz, Effet pH, pH effect, Efecto pH, Effet température, Temperature effect, Efecto temperatura, Force ionique, Ionic strength, Fuerza iónica, Force surface, Surface forces, Interpolymère, Interpolymer, Interpolímero, Microscopie force atomique, Atomic force microscopy, Microscopía fuerza atómica, Mécanisme formation, Formation mechanism, Mecanismo formacion, Méthode étude, Investigation method, Método estudio, Polyélectrolyte, Polyelectrolyte, Polielectrolito, Protéine, Protein, Proteína, Solution chimique, Chemical solution, Solución química, AFM, DLS, PEC, PEM, Relaxation time, and Rheology

Polyelectrolyte complex formation is a well-studied subject in colloid science. Several types of complex formation have been studied, including PEMs, macroscopic polyelectrolyte complexes, soluble complexes and polyelectrolyte complex micelles. The chemical nature of the complex-forming polyelectrolytes and the environmental conditions (e.g., pH, ionic strength and temperature) influence the final structural properties of these complexes. This chapter deals with the kinetics of polyelectrolyte complex formation and discusses how ionic strength, charge density and pH influence the dynamics of the complexes, which can range from glass-like (solid) precipitates to liquid-like phases. The switching between the glass-like and liquid-like phase as a function of the ionic strength has a strong analogy to the phase behaviour of polymer melts as function of temperature. By performing calorimetry during complex formation it has been found that the enthalpy of complex formation of systems that form glass-like phases has an opposite sign to the enthalpy of systems that form liquid-like phases, i.e., the formation of glass-like phases is exothermic and the formation of liquid-like phases is endothermic. The free energy (ΔfG), enthalpy (ΔfH) and entropy (ΔfS) of polyelectrolyte complex formation and how they vary as a function of the ionic strength will be discussed. Results from dynamic light scattering (DLS) titrations, Atomic Force Microscopy (AFM), surface force measurements and rheology will be used to illustrate how differences in kinetics show up in experiments on colloidal micellar systems. In the section on DLS titrations, three-component systems containing two oppositely charged polyelectrolytes and protein molecules will be discussed. This chapter concludes with a section dedicated to the complex formation of oppositely charged protein molecules.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Propriétés et caractérisation, Properties and characterization, Cristallisation, Crystallization, Lactone polymère, Lactone polymer, Lactona polímero, Caprolactone polymère, Polycaprolactone, Caprolactona polímero, Cinétique, Kinetics, Cinética, Cristallisation isotherme, Isothermal crystallization, Cristalización isotérmica, Cristallisation état fondu, Melt crystallization, Cristalización estado fundido, Effet température, Temperature effect, Efecto temperatura, Etude comparative, Comparative study, Estudio comparativo, Etude expérimentale, Experimental study, Estudio experimental, Nucléation, Nucleation, Nucleación, Polymère linéaire, Linear polymer, Polímero lineal, Polymère monodispersé, Monodispersed polymer, Polímero monodispersado, Relation masse moléculaire propriété, Molecular weight property relation, Relación masa molecular propiedad, Température transformation, Transformation temperature, Temperatura transformación, Autonucléation, (SSA), Crystallization, Cyclic poly(ε-caprolactone), Self-nucleation, and Successive Self-nucleation and Annealing

A series of low polydispersity cyclic PCL samples (C-PCLs), as well as their linear analogs (L-PCLs), were synthesized by click chemistry in a number average molecular weight (Mn) range of 2-22 kg/mol. They were investigated by Polarized Light Optical Microscopy (PLOM) and Differential Scanning Calorimetry (DSC). The nucleation and overall crystallization kinetics were studied, as well as their self-nucleation behavior and SSA (Successive Self-nucleation and Annealing) thermal fractionation. Cyclic PCLs were found to nucleate and crystallize faster than linear PCLs due to: (a) faster diffusion of C-PCL chains and (b) larger supercoolings of C-PCLs at any given crystallization temperature, as compared to L-PCLs. A bell shape curve was obtained when the overall crystallization rate was examined as a function of Mn, this effect is probably due to a competition between nucleation and diffusion. It was found for the first time, that since cyclic molecules have lower entanglement densities, they can quickly recover their pseudo-equilibrium compact coil conformations upon melting and therefore exhibit much smaller crystalline memory effects than their linear counterparts of identical chain lengths. SSA revealed that C-PCLs are more sensitive to annealing than L-PCLs because their ring topology and limited lamellar chain folding facilitates crystal thickening.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères d'origine naturelle, Natural polymers, Amidon et polyosides divers, Starch and polysaccharides, Polymères organiques, Organic polymers, Propriétés et caractérisation, Properties and characterization, Propriétés spéciales (catalyseur, réactif ou support), Special properties (catalyst, reagent or carrier), Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Pharmacologie. Traitements medicamenteux, Pharmacology. Drug treatments, Pharmacologie générale, General pharmacology, Technologie pharmaceutique. Industrie pharmaceutique, Pharmaceutical technology. Pharmaceutical industry, Adhérence, Adhesion, Adherencia, Article synthèse, Review, Artículo síntesis, Cinétique, Kinetics, Cinética, Libération, Release, Liberación, Muqueuse, Mucosa, Mécanisme, Mechanism, Mecanismo, Polymère vecteur, Control release polymer, Polímero vector, Vecteur médicament, Drug carrier, Vector medicamento, Mucoadhérence, Mucoadhésif, Mucoadhesive drug delivery systems, Mucoadhesive natural, synthetic and semi-synthetic polymers, and Pharmaceutical materials science pharmaceutical research and development

The presence of a mucus layer that covers the surface of a variety of organs has been capitalized to develop mucoadhesive dosage forms that remain in the administration site for prolonged times, increasing the local and/or systemic bioavailability of the administered drug. The emergence of micro and nanotechnologies together with the implementation of non-invasive and painless administration routes has revolutionized the pharmaceutical market and the treatment of disease. Aiming to overcome the main drawbacks of the oral route and to maintain patient compliance high, the engineering of innovative drug delivery systems administrable by mucosal routes has come to light and gained the interest of the scientific community due to the possibility to dramatically change pharmacokinetics. In addition, to achieve the goal of mucosal drug administration, the development of biomaterials has been refined to fit specific applications. The present review initially describes the potential of nano-drug delivery systems conceived for mucosal administration by diverse non-parenteral routes (e.g., oral, inhalatory, etc.). Then, the benefit of the incorporation of mucoadhesive polymers into the structure of these innovative pharmaceutical products to prolong their residence time in the administration site and the release of the drug cargo will be discussed with focus in the developments of the last decade. In addition, the regulatory status of the most extensively used mucoadhesive polymers will be emphasized. Finally, a thorough overview of the different pharmaceutical applications of mucoadhesive polymers will be addressed.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Propriétés et caractérisation, Properties and characterization, Propriétés des solutions et des gels, Solution and gel properties, Cinétique, Kinetics, Cinética, Congélation, Freezing, Congelación, Diffusion RX centrale, Small angle X ray scattering, Difusión rayo X central, Effet solvant, Solvent effect, Efecto solvente, Enchevêtrement moléculaire, Molecular entanglement, Encabestradura molecular, Etat actuel, State of the art, Estado actual, Gel physique, Physical gel, Gel físico, Gélification, Gelation, Gelificación, Hydrogel, Hidrogel, Liaison hydrogène, Hydrogen bond, Enlace hidrógeno, Macroporosité, Macroporosity, Macroporosidad, Solution aqueuse, Aqueous solution, Solución acuosa, Vinylique alcool polymère, Polyvinylalcohol, Vinílico alcohol polímero, Cristallisation confinée, Confined polymer crystallization, Cryotropic gelation, Ostwald stage-rule, Poly(vinyl alcohol) hydrogels, and Time-resolving small angle neutron scattering

Aqueous poly(vinyl alcohol) (PVA) solutions subjected to cryogenic treatment form strong physical gels. The cryogenic treatment basically consists of freezing an initially homogeneous polymer solution at low temperatures, storing in the frozen state for a definite time, and defrosting. These gels are of great interest for biotechnology, medicine, the food industry, and many other applications. The outstanding properties of these systems depend on a complex macroporous architecture, whereby PVA chains and water molecules are organized over different hierarchical length scales. The structure and the principal processes subtending the formation of these systems are discussed in the framework of our current understanding of polymer gels. These processes involve formation of ice crystals, PVA crystallization, liquid-liquid phase separation, hydrogen bonding, and entanglements. Small angle neutron scattering is used to follow the cryotropic gelation of PVA/water solutions and detailed information is extracted concerning the gelation mechanism and kinetic parameters related to the formation of these complex systems.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Propriétés et caractérisation, Properties and characterization, Propriétés des solutions et des gels, Solution and gel properties, Agrégation, Aggregation, Agregación, Cinétique, Kinetics, Cinética, Etude théorique, Theoretical study, Estudio teórico, Interaction hydrophobe, Hydrophobic interaction, Interaction interparticulaire, Interparticle interaction, Interacción interpartículas, Interaction électrostatique, Electrostatic interaction, Interacción electrostática, Interpolymère, Interpolymer, Interpolímero, Modélisation, Modeling, Modelización, Morphologie, Morphology, Morfología, Particule colloïdale, Colloid particle, Partícula coloidal, Polyélectrolyte, Polyelectrolyte, Polielectrolito, Simulation numérique, Numerical simulation, Simulación numérica, Solvatation, Solvation, Solvatación, Suspension particule, Particle suspension, Suspensión partícula, Charged particles, Colloids, and Polyelectrolyte complex (PEC)

This chapter reviews the recent progress in aggregation of colloidal particles with long-range interactions, including simple colloids and polyelectrolytes. The relevant interactions between colloidal particles, including Born repulsion, van der Waals, electrostatic, structural solvation, hydrophobic hydrodynamic interactions and attraction between like-charge colloids, charge nonuniformity, and adsorbed polymer, are analyzed. The main types of computer models used for simulation of cluster morphology and aggregation kinetics of the different interacting species (similarly and oppositely charged particles and polyelectrolytes) are reviewed. The main scaling laws for different aggregating kernels that describe diffusion-limited, reaction-limited, gelling, and retarded aggregations are also presented and analyzed.

Biochemistry, molecular biology, biophysics, Biochimie, biologie moléculaire, biophysique, General chemistry, physical chemistry, Chimie générale, chimie physique, Nanotechnologies, nanostructures, nanoobjects, Nanotechnologies, nanostructures, nanoobjets, Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Préparation, cinétique, thermodynamique, mécanisme et catalyseurs, Preparation, kinetics, thermodynamics, mechanism and catalysts, Polymères à propriétés spéciales, Polymers with particular properties, Cinétique, Kinetics, Cinética, Copolymère biséquencé, Diblock copolymer, Copolímero bisecuencia, Effet concentration, Concentration effect, Efecto concentración, Etude expérimentale, Experimental study, Estudio experimental, Micellisation, Micellization, Micelización, Méthacrylate de sodium copolymère, Sodium methacrylate copolymer, Metacrilato de sodio copolímero, Méthacrylique acide copolymère, Methacrylic acid copolymer, Metacrílico ácido copolímero, Polymère amphiphile, Amphiphilic polymer, Polímero amfifilo, Polymérisation transfert atome, Atom transfer polymerization, Polimerización transferencia atomo, Polyélectrolyte, Polyelectrolyte, Polielectrolito, Propriété rhéologique, Rheological properties, Propiedad reológica, Préparation, Preparation, Preparación, Relation structure propriété, Property structure relationship, Relación estructura propiedad, Solution aqueuse, Aqueous solution, Solución acuosa, Styrène copolymère, Styrene copolymer, Estireno copolímero, Viscosité cisaillement, Shear viscosity, Viscosidad cizalla, ATRP, Amphiphilic block copolymers, Gel rheology, and Percolation

Following our previous investigation on the effect of molecular architecture on the rheology of Polystyrene-b-Poly(sodium methacrylate) copolymers (PS-b-PMAA), we consider here diblock PS-b-PMAA copolymers characterized by a different length of either the hydrophilic or the hydrophobic block. Various copolymers characterized by different PS or PMAA block length have been prepared by ATRP (kinetics is also discussed) and studied from the point of view of their rheological behaviour in water. To the best of our knowledge, this is the first systematic investigation concerning the effect of block length on the rheology of diblock polyelectrolytes. We found that the hydrophobic block length has small influence on the rheology. Surprisingly, the polymers with shortest PMAA blocks yield the strongest gels at high concentration. A simple model based on the classical theories of self-assembly and percolation of amphiphilic polymers has been here developed in order to explain the observed data.

General chemistry, physical chemistry, Chimie générale, chimie physique, Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Propriétés et caractérisation, Properties and characterization, Cristallisation, Crystallization, Caprolactone polymère, Polycaprolactone, Caprolactona polímero, Cinétique, Kinetics, Cinética, Condition non isotherme, Non isothermal condition, Condición no isoterma, Cristallisation isotherme, Isothermal crystallization, Cristalización isotérmica, Cristallisation état fondu, Melt crystallization, Cristalización estado fundido, Effet composition, Composition effect, Efecto composición, Ethylène oxyde polymère, Ethylene oxide polymer, Etileno óxido polímero, Etude expérimentale, Experimental study, Estudio experimental, Mécanisme, Mechanism, Mecanismo, Mélange polymère, Polymer blends, Nucléation, Nucleation, Nucleación, Séparation phase, Phase separation, Separación fase, Fluctuation-assisted crystallization, Interface-assisted crystallization, Liquid-liquid phase separation, and PEO/PCL blend

The nucleation and crystallization of poly(ethylene oxide) (PEO) and poly(ε-caprolactone) (PCL) in the PEO/ PCL blends have been investigated by means of optical microscopy (OM) and differential scanning calorimetry (DSC). During the isothermal or nonisothermal crystallization process, when the adjacent PEO is in the molten state, PCL nucleation preferentially occurs at the PEO and PCL interface; after the crystallization of the adjacent PEO, much more PCL nuclei form on the surface of the PEO crystal. However, PEO crystallizes normally and no interfacial nucleation occurs in the blend. The concentration fluctuation caused by liquid-liquid phase separation (LLPS) induces the motion of PEO and PCL chains through interdiffusion and possible orientation of chain segments. The oriented PEO chain segments can assist PCL nucleation, and the heterogeneous nucleation ability of PEO increases with the orientation of PEO chains. Oriented PCL chain segments have no heterogeneous nucleation ability on PEO. It is postulated that the interfacial nucleation of PCL in the PEO/PCL blend follows the combination offluctuation-assisted crystallization and interface-assisted crystallization mechanisms.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Préparation, cinétique, thermodynamique, mécanisme et catalyseurs, Preparation, kinetics, thermodynamics, mechanism and catalysts, Polycondensation, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Biotechnologie, Biotechnology, Méthodes. Procédés. Technologies, Methods. Procedures. Technologies, Bioconversions. Hémisynthèses, Bioconversions. Hemisynthesis, Alcanoate(hydroxy) polymère, Alkanoate(hydroxy) polymer, Alcanoato(hidroxi) polímero, Article synthèse, Review, Artículo síntesis, Biosynthèse, Biosynthesis, Biosíntesis, Cinétique, Kinetics, Cinética, Cristallinité, Crystallinity, Cristalinidad, Cristallisation, Crystallization, Cristalización, Culture microorganisme, Microorganism culture, Cultivo microorganismo, Ester polymère, Ester polymer, Ester polímero, Mécanisme réaction, Reaction mechanism, Mecanismo reacción, Origine microbienne, Microbial origin, Origen microbiano, Polymère aliphatique, Aliphatic polymer, Polímero alifático, Propriété mécanique, Mechanical properties, Propiedad mecánica, Structure cristalline, Crystalline structure, Estructura cristalina, Distribution composition chimique, Isodimorphisme, Biopolymer, Microbial polyesters, Poly((R)-3-hydroxybutyrate), Poly((R)-3-hydroxybutyrate-co-3-hydroxyvalerate), and Polyhydroxyalkanoates

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Préparation, cinétique, thermodynamique, mécanisme et catalyseurs, Preparation, kinetics, thermodynamics, mechanism and catalysts, Polymères à propriétés spéciales, Polymers with particular properties, Acrylate de butyle copolymère, Butyl acrylate copolymer, Acrilato de butilo copolímero, Cinétique, Kinetics, Cinética, Cire paraffine, Paraffin wax, Cera parafina, Copolymérisation radicalaire, Radical copolymerization, Copolimerización radical, Copolymérisation suspension, Suspension copolymerization, Copolimerización suspensión, Dimension particule, Particle size, Dimensión partícula, Effet température, Temperature effect, Efecto temperatura, Etude expérimentale, Experimental study, Estudio experimental, Microcapsule, Microcápsula, Morphologie, Morphology, Morfología, Méthacrylate de méthyle copolymère, Methyl methacrylate copolymer, Metacrilato de metilo copolímero, Propriété interface, Interface properties, Propiedad interfase, Propriété thermique, Thermal properties, Propiedad térmica, Préparation, Preparation, Preparación, Relation mise en oeuvre structure, Structure processing relationship, Relación puesta en marcha estructura, Température transition vitreuse, Glass transition temperature, and Temperatura transición vítrosa

PRS® paraffin wax was encapsulated by means of suspension-like copolymerization of methyl methacrylate (MMA) with butyl acrylate (BA). The effects of the polymeric shell dry glass transition temperature (Tg) and the reaction temperature (Tr) were then studied. Additionally, the evolution of particle diameter, molecular weight, conversion, and Tg during polymerization was also researched. The chemical properties of the shell material (acrylic polymer), together with those found in the core material (PRS® paraffin wax), for instance: polarity and interfacial tensions, largely determine whether the morphology of the microcapsules will be thermodynamically favored or not. The high polarity of MMA (γ0 = 18 mN m-1) and BA (γ0 = 24 mN m-1) should provide a thermodynamic driving force to cover the paraffin wax droplet which would result in a core/shell thermodynamically favored structure. However, most systems are defined by kinetics rather than thermodynamics such as the monomers dry Tg and Tr It was observed that penetration of polymer radical chains was severely limited when the dry Tg was ≥10°C above the reaction temperature, resulting in irregular and undifferentiated particles. However, penetration did occur when the copolymeric shell dry Tg was ~10°C below the reaction temperature which led to uniform and spherical particles being synthesized.

Environment, Environnement, Materials, Matériaux, Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Propriétés et caractérisation, Properties and characterization, Rhéologie et viscoélasticité, Rheology and viscoelasticity, Propriétés thermiques et thermodynamiques, Thermal and thermodynamic properties, Cristallisation, Crystallization, Ester copolymère, Ester copolymer, Ester copolímero, Allongement chaîne, Chain elongation, Alargamiento cadena, Butyrate(hydroxy) copolymère, Butyrate(hydroxy) copolymer, Butirato(hidroxi) copolímero, Chaleur transformation, Heat of transformation, Calor transformación, Cinétique, Kinetics, Cinética, Copolymère aliphatique, Aliphatic copolymer, Copolímero alifático, Cristallisation isotherme, Isothermal crystallization, Cristalización isotérmica, Cristallisation état fondu, Melt crystallization, Cristalización estado fundido, Effet concentration, Concentration effect, Efecto concentración, Etude expérimentale, Experimental study, Estudio experimental, Méthacrylate de glycidyle copolymère, Glycidyl methacrylate copolymer, Metacrilato de glicidilo copolímero, Méthode phase fondue, Growth from melt, Método fase fundida, Origine microbienne, Microbial origin, Origen microbiano, Propriété rhéologique, Rheological properties, Propiedad reológica, Relation mise en oeuvre propriété, Property processing relationship, Relación puesta en marcha propiedad, Stabilisation thermique, Thermal stabilization, Estabilización térmica, Stabilité thermique, Thermal stability, Estabilidad térmica, Styrène dérivé copolymère, Styrene derivative copolymer, Estireno derivado copolímero, Température transformation, Transformation temperature, Temperatura transformación, Valérate(hydroxy) copolymère, Valerate(hydroxy) copolymer, Valerato(hidroxi) copolímero, Viscosité complexe, Chain extender, Crystallization, PHBV, Rheology, and Thermal degradation

Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), a semi-polycrystalline biopolymer from the polyhydroxyalkanonate family has in recent years become a commercial bioplastic with mechanical properties comparable to isotactic polypropylene and enhanced O2, CO2 and H2O barrier properties. However, its brittleness and sensitivity to thermal and hydrolysis degradations restrict its applications. To overcome the problems associated with degradation during processing blending of PHBV and an epoxy-functionalized chain extender (Joncryl® ADR-4368 S) was conducted in a twin screw extruder. The effect of concentration of the chain extender on thermal, crystallization and rheological behaviours of PHBV was investigated. Thermal gravimetric analysis results indicated improvement in the resistance to thermal decomposition of PHBV by introducing the chain extender. This was accompanied with calculation of thermal degradation activation energy (Ea) using the Flyn-Walls-Ozawa method which confirmed increase of Ea with the increase in content of the chain extender. The rheological behaviour and crystallization of modified PHBV was characterized by rotational rheometry and differential scanning calorimetry techniques, respectively. The results show that addition of chain extender enhanced viscosity of PHBV and also reduce the rate of crystallization.

General chemistry, physical chemistry, Chimie générale, chimie physique, Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Propriétés et caractérisation, Properties and characterization, Propriétés des solutions et des gels, Solution and gel properties, Acrylamide dérivé polymère, Acrylamide derivative polymer, Acrilamida derivado polímero, Cinétique, Kinetics, Cinética, Dispersion aqueuse, Aqueous dispersion, Dispersión acuosa, Dissolution, Disolución, Effet température, Temperature effect, Efecto temperatura, En semi continu, Semicontinuous, En semicontinuo, Etude expérimentale, Experimental study, Estudio experimental, Latex, Látex, Mécanisme formation, Formation mechanism, Mecanismo formacion, Mécanisme, Mechanism, Mecanismo, Particule sous micronique, Submicron particle, Partícula submicrónica, Polymérisation ensemencée, Seeded polymerization, Polimerización sembrada, Polymérisation radicalaire, Free radical polymerization, Polimerización radicalar, Polymérisation émulsion, Emulsion polymerization, Polimerización emulsión, Préparation, Preparation, Preparación, Acrylamide(N-isopropyl) polymère, Polymère thermosensible, Polymérisation sans agent surface, Disintegration, Poly(n-isopropylacrylamide), Polymer dissolution, Semicontinuous heterophase polymerisation, and Swelling

Crosslinker-free poly(n-isopropylacrylamide) (polyNIPAM) particles produced by conventional emulsifier-free heterophase polymerisations contain gels and do not easily and completely disintegrate in water, if at all. These particles, when cooled below lower critical solution temperature (LCST) swell first and then gradually shrink, due to their slow rate of disintegration. We first show that only particles formed using very low monomer concentration, which have a low molecular weight, are fully soluble in water. Then, we describe a seeded semicontinuous route which was designed in order to be able to maintain a low monomer concentration in water in the course of reaction and control the length and location of growing chains. Nanoparticles produced via semicontinuous approach not only disintegrated in water very quickly but also dissolved in water completely as soon as LCST was reached. This finding may also find applications in technologically important processes for dissolution of macromolecules in solvents.

Electronics, Electronique, Condensed state physics, Physique de l'état condensé, Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Préparation, cinétique, thermodynamique, mécanisme et catalyseurs, Preparation, kinetics, thermodynamics, mechanism and catalysts, Polymères à propriétés spéciales, Polymers with particular properties, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Pharmacologie. Traitements medicamenteux, Pharmacology. Drug treatments, Pharmacologie générale, General pharmacology, Technologie pharmaceutique. Industrie pharmaceutique, Pharmaceutical technology. Pharmaceutical industry, Lactone copolymère, Lactone copolymer, Lactona copolímero, Propriété biologique, Biological properties, Propiedad biológica, Propriété optique, Optical properties, Propiedad óptica, Propriété électrique, Electrical properties, Propiedad eléctrica, Acide copolymère, Acid copolymer, Acido copolímero, Caprolactone copolymère, Caprolactone copolymer, Caprolactona copolímero, Cinétique, Kinetics, Cinética, Colorant organique, Organic dye, Colorante orgánico, Conductivité électrique, Electrical conductivity, Conductividad eléctrica, Copolymère greffé, Graft copolymer, Copolímero injertado, Copolymère triséquencé, Triblock copolymer, Copolímero trisecuencia, Cytotoxicité, Cytotoxicity, Citotoxicidad, Etude expérimentale, Experimental study, Estudio experimental, Fluorescence, Fluorescencia, Greffage, Grafting, Injerto, In vitro, Libération, Release, Liberación, Polymère amphiphile, Amphiphilic polymer, Polímero amfifilo, Polymère conducteur, Conducting polymers, Polymère vecteur, Control release polymer, Polímero vector, Polymérisation ouverture cycle, Ring opening polymerization, Polimerización abertura ciclo, Polymérisation oxydante, Oxidative polymerization, Polimerizacion oxidante, Polyélectrolyte, Polyelectrolyte, Polielectrolito, Propriété électrochimique, Electrochemical properties, Propiedad electroquímica, Préparation, Preparation, Preparación, Réaction successive, Successive reaction, Reacción consecutiva, Stabilité thermique, Thermal stability, Estabilidad térmica, THF, Tetrahydrofurane, Furano(tetrahidro), Terpolymère, Terpolymer, Terpolímero, Tétrahydrofurane copolymère, Tetrahydrofuran copolymer, Tetrahidrofurano copolímero, Vecteur médicament, Drug carrier, Vector medicamento, pH, Aniline dérivé copolymère, Aniline derivative copolymer, Aniline(3-carboxy) copolymère, Characterization, Conductivity, Cyclic voltammetry, and Drug release system

The poly(tetrahydrofuran) (PTHF) grafted poly(caprolactone)-poly(anthranilicacid)-poly(caprolactone) (PCL-PAA-PCL) co-polymer system was synthesized by using a prepolymer under nitrogen atmosphere in the presence of a stannous octoate catalyst. The [M0/l0] was maintained at 100. The polymers at each stage was characterized by various analytical techniques like FTIR spectroscopy, NMR spectroscopy, UV-visible spectroscopy, fluorescence spectroscopy, cyclic voltammetry, DSC, TGA, conductivity, FESEM, solubility test, cytotoxicity and drug release study. The results obtained here in the present investigation are critically compared with the literature values.

Biochemistry, molecular biology, biophysics, Biochimie, biologie moléculaire, biophysique, Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Propriétés et caractérisation, Properties and characterization, Propriétés des solutions et des gels, Solution and gel properties, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Chirurgie (generalites). Transplantations, greffes d'organes et de tissus. Pathologie des greffons, Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases, Technologie. Biomatériaux. Equipements, Technology. Biomaterials. Equipments, Propriété biologique, Biological properties, Propiedad biológica, Propriété mécanique, Mechanical properties, Propiedad mecánica, Acrylamide dérivé copolymère, Acrylamide derivative copolymer, Acrilamida derivado copolímero, Acrylate copolymère, Acrylate copolymer, Acrilato copolímero, Acrylique acide copolymère, Acrylic acid copolymer, Acrílico ácido copolímero, Amidoamine copolymère, Amidoamine copolymer, Amidoamina copolímero, Amidoamine polymère, Amidoamine polymer, Amidoamina polímero, Biocompatibilité, Biocompatibility, Biocompatibilidad, Biodégradabilité, Biodegradability, Biodegradabilidad, Biomatériau, Biomaterial, Cellule mésenchymateuse, Mesenchymal cell, Célula mesenquimatosa, Cellule souche, Stem cell, Célula primitiva, Charpente, Framework, Armadura, Cinétique, Kinetics, Cinética, Copolymérisation radicalaire, Radical copolymerization, Copolimerización radical, Encapsulation, Encapsulación, Etude expérimentale, Experimental study, Estudio experimental, Forme injectable, Injectable form, Forma inyectable, Gonflement, Swelling, Inflamiento, Gélification, Gelation, Gelificación, Génie tissulaire, Tissue engineering, Ingeniería de tejidos, Hydrogel, Hidrogel, Hydrolyse, Hydrolysis, Hidrólisis, In vitro, Module compression, Bulk modulus, Módulo volumétrico, Méthacrylate de glycidyle copolymère, Glycidyl methacrylate copolymer, Metacrilato de glicidilo copolímero, Préparation, Preparation, Preparación, Réticulation, Crosslinking, Reticulación, Solution aqueuse, Aqueous solution, Solución acuosa, Tissu osseux, Osseous tissue, Tejido óseo, Acrylamide(N-isopropyl) copolymère, Copolymère sensible stimuli, Gel hybride, and Quaterpolymère

Injectable, dual-gelling hydrogels were successfully developed through the combination of physical thermogellation at 37 °C and favorable amine:epoxy chemical cross-linking. Poly(N-isopropylacrylamide)-based thermogelling macromers with a hydrolyzable lactone ring and epoxy pendant groups and a biodegradable diamine-functionalized polyamidoamine cross-linker were synthesized, characterized, and combined to produce nonsyneresing and bioresorbable hydrogels. Differential scanning calorimetry and oscillatory rheometry demonstrated the rapid and dual-gelling nature of the hydrogel formation. The postgelation dimensional stability, swelling, and mechanical behavior of the hydrogel system were shown to be easily tuned in the synthesis and formulation stages. The leachable products were found to be cytocompatible under all conditions, while the degradation products demonstrated a dose- and time-dependent response due to solution osmolality. Preliminary encapsulation studies showed mesenchymal stem cell viability could be maintained for 7 days. The results suggest that injectable and thermally and chemically cross-linkable hydrogels are promising alternatives to prefabricated biomaterials for tissue engineering applications, particularly for cell delivery.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Préparation, cinétique, thermodynamique, mécanisme et catalyseurs, Preparation, kinetics, thermodynamics, mechanism and catalysts, Polymères à propriétés spéciales, Polymers with particular properties, Acrylate copolymère, Acrylate copolymer, Acrilato copolímero, Adsorption liquide solide, Liquid solid adsorption, Adsorción líquido sólido, Amine copolymère, Amine copolymer, Amina copolímero, Cinétique, Kinetics, Cinética, Coefficient frottement, Friction coefficient, Coeficiente roce, Copolymère greffé, Graft copolymer, Copolímero injertado, Copolymère vivant, Living copolymer, Copolímero viviente, Etude expérimentale, Experimental study, Estudio experimental, Greffage, Grafting, Injerto, Hydrolyse, Hydrolysis, Hidrólisis, Lubrification, Lubrication, Lubricación, Modification chimique, Chemical modification, Modificación química, Méthacrylate copolymère, Methacrylate copolymer, Metacrilato copolímero, Méthacrylate d'hydroxyéthyle copolymère, Hydroxyethyl methacrylate copolymer, Metacrilato de hidroxietilo copolímero, Méthacrylate d'hydroxyéthyle polymère, Hydroxyethyl methacrylate polymer, Metacrilato de hidroxietilo polímero, Méthacrylique acide copolymère, Methacrylic acid copolymer, Metacrílico ácido copolímero, Polymère amphiphile, Amphiphilic polymer, Polímero amfifilo, Polymérisation transfert atome, Atom transfer polymerization, Polimerización transferencia atomo, Préparation, Preparation, Preparación, Siloxane(diméthyl) polymère, Dimethylsiloxane polymer, Siloxano(dimetil) polímero, Solution aqueuse, Aqueous solution, Solución acuosa, Terpolymère, Terpolymer, Terpolímero, Tribologie, Tribology, Tribología, Acrylate de 2-méthoxyéthyle copolymère, Méthacrylate de 2-diméthylaminoéthyle copolymère, and Méthacrylate de t-butyle copolymère

Amphiphilic anionic and cationic graft copolymers possessing poly(2-hydroxyethyl methacrylate) (PHEMA) backbone and poly(methacrylic acid), poly(2-methoxyethyl acrylate-co-methacrylic acid), and poly(2-methoxyethyl acrylate-co-2-(dimethylamino)ethyl methacrylate) grafts are constructed by merging reversible addition―fragmentation chain transfer (RAFT) polymerization, copper-mediated atom transfer radical polymerization (ATRP), and a selective deprotection reaction. Initially, multifunctional ATRP macroinitiators based on PHEMA backbone are prepared by RAFT polymerization. Then ATRP of the corresponding monomers followed by deblocking reaction leads to well-defined amphiphiles with narrow molecular weight distributions (PDI ≤ 1.29) and varying content of methacrylic acid. The graft copolymers showed effective surface adsorption and lubrication for self-mated poly(dimethylsiloxane) (PDMS) contacts in physiological salt concentration. This is indebted from dilution of the charges along the grafted chains by balancing neutral/ charged repeating units to minimize the accumulated charge repulsion on neutral surface. Improved lubricating properties of the graft copolymers compared to the block copolymer counterparts further support superior stability of graft copolymers on surfaces.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Préparation, cinétique, thermodynamique, mécanisme et catalyseurs, Preparation, kinetics, thermodynamics, mechanism and catalysts, Copolymérisation, Copolymerization, Acrylamide dérivé copolymère, Acrylamide derivative copolymer, Acrilamida derivado copolímero, Caoutchouc thermoplastique, Thermoplastic rubber, Caucho termoplástico, Cinétique, Kinetics, Cinética, Copolymérisation radicalaire, Radical copolymerization, Copolimerización radical, Etude expérimentale, Experimental study, Estudio experimental, Isocyanate organique, Organic isocyanate, Isocianato orgánico, Méthacrylate de méthyle copolymère, Methyl methacrylate copolymer, Metacrilato de metilo copolímero, Polyaddition, Poliadición, Polymère téléchélique, Telechelic polymer, Polímero telechélico, Préparation, Preparation, Preparación, Rapport réactivité, Reactivity ratio, Relación reactividad, Structure moléculaire, Molecular structure, Estructura molecular, Transfert chaîne, Chain transfer, Transferencia en cadena, Uréthanne copolymère, Urethane copolymer, Uretano copolímero, Uréthanne élastomère, Polyurethane elastomer, Uretano elastómero, Addition fragmentation réversible, activated esters, functional side chains, poly(methymethacrylate) copolymers, reversible addition fragmentation chain transfer polymerization, and telechelics

The synthetic route for the preparation of α,ω-isocyanate-telechelic poly(methyl methacrylate-co-acryloxysuccinimide) and α,ω-isocyanate-telechelic poly(methyl methacrylate-co-acrylamidohexanoic succinimide) soft segments is presented. The strategy includes reversible addition fragmentation chain transfer (RAFT) copolymerization and two post polymerization modification steps. The RAFT polymerizations result in copolymers with an activated ester proportion within the polymer chains of 8% N-acryloxysuccinimide and 5% 6-acrylamidohexanoic succinimide. The reactivity ratios of the monomer pairs were determined. In a first post polymerization reaction carboxylic acid homo telechelic polymers were prepared by reacting the ω-dithiobenzoate end-group with an excess of azobis(cyanovaleric acid). In a second modification step the α- and ω-carboxylic acid end-groups were reacted with hexamethylene diisocyanate and 100% isocyanate telechelic copolymers were obtained. Finally segmented polyurethanes were prepared by coupling hexamethylene diisocyanate (HDI) end capped soft segments with hard segments composed of 1,4-butanediol and HDI.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Préparation, cinétique, thermodynamique, mécanisme et catalyseurs, Preparation, kinetics, thermodynamics, mechanism and catalysts, Polycondensation, Activité catalytique, Catalyst activity, Actividad catalítica, Cinétique, Kinetics, Cinética, Composé de l'iminium, Iminium compounds, Iminio compuesto, Cristallinité, Crystallinity, Cristalinidad, Dérivé de l'imidazole, Imidazole derivatives, Imidazol derivado, Energie activation, Activation energy, Energía activación, Ether cyclique copolymère, Cyclic ether copolymer, Eter cíclico copolímero, Ether cyclique polymère, Cyclic ether polymer, Eter cíclico polímero, Ethylène oxyde copolymère, Ethylene oxide copolymer, Etileno óxido copolímero, Ethylène oxyde polymère, Ethylene oxide polymer, Etileno óxido polímero, Etude expérimentale, Experimental study, Estudio experimental, Lactique acide copolymère, Lactic acid copolymer, Láctico ácido copolímero, Liquide ionique, Ionic liquid, Líquido iónico, Mouillabilité, Wettability, Remojabilidad, Polycondensation, Condensation polymerization, Policondensación, Polymère aliphatique, Aliphatic polymer, Polímero alifático, Propriété mécanique, Mechanical properties, Propiedad mecánica, Propriété surface, Surface properties, Propiedad superficie, Préparation, Preparation, Preparación, Réaction catalytique, Catalytic reaction, Reacción catalítica, Structure moléculaire, Molecular structure, Estructura molecular, Sulfonate, Sulfonato, and Imidazolium composé

Poly(lactic acid)-poly(ethylene glycol) copolymers were synthesized under the catalysis of multi-SO3H-functionalized ionic liquid. Compared to the ordinary ionic liquids and the traditional Lewis acid catalysts, the ionic liquids with multi-sulfonic acid groups were more catalytically active, and the reaction conversion rate reached up to 97.8 %. The molecular weight of the resulting copolymer was 5.69 x 104 g mol-1 and the degree of crystallinity was 42.9 %. The copolymers were also of higher hydrophilicity and better mechanical properties. The reaction kinetics of copolymerization was analyzed. The intrinsically high catalytic activity of multi-SO3H groups originated from the lower activation energy and the higher free acidity. The recovering catalytic activity of the multi-SO3H ionic liquid catalyst was higher, suggesting that it is a recyclable, environmentally friendly catalyst.

Electronics, Electronique, Condensed state physics, Physique de l'état condensé, Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Physicochimie de surface, Surface physical chemistry, Matériaux adsorbants, Adsorbents, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Préparation, cinétique, thermodynamique, mécanisme et catalyseurs, Preparation, kinetics, thermodynamics, mechanism and catalysts, Polymères à propriétés spéciales, Polymers with particular properties, Adsorbant organique, Organic adsorbent, Adsorbente orgánico, Adsorption liquide solide, Liquid solid adsorption, Adsorción líquido sólido, Capacité adsorption, Adsorption capacity, Capacidad adsorción, Cinétique, Kinetics, Cinética, Colorant organique, Organic dye, Colorante orgánico, Composé inclusion, Inclusion compound, Compuesto inclusión, Cyclodextrine, Cyclodextrin, Ciclodextrina, Etude expérimentale, Experimental study, Estudio experimental, Iode, Iodine, Iodo, Milieu aqueux, Aqueous medium, Medio acuoso, Morphologie, Morphology, Morfología, Mécanisme formation, Formation mechanism, Mecanismo formacion, Mécanisme, Mechanism, Mecanismo, Nanofibre, Nanofiber, Nanofibra, Polymère conducteur, Conducting polymers, Polymérisation oxydante, Oxidative polymerization, Polimerizacion oxidante, Polymérisation sur matrice, Template polymerization, Polimerización sobre matriz, Préparation, Preparation, Preparación, Pyrrole polymère, Pyrrole polymer, Pirrol polímero, pH, Structure hiérarchique, Acid Red G, Adsorption, Hierarchical structure, and Polypyrrole (PPy)

The polypyrrole nano-fibers with hierarchical structure were synthesized in α-CD/I2 inclusion compound solution via chemical oxidation by using FeCl3 as the oxidant. The formation of the hierarchical structured PPy was certified by Field Emission Scanning Electronic Microscope (SEM). Fourier transform infrared spectroscopy (FT-IR) results showed that the molecular structure of the prepared PPy backbone is same as the conventional PPy. From the results of X-ray fluorescence spectrometer (XRF) and X-ray diffraction (XRD) measurements, the α-CD/I2-Fe2+ is as the soft-template during the synthesis process of PPy with hierarchical structure. Some I- ions retained in the backbone of the prepared PPy were as the counter ion after rinse. PPy with hierarchical structure shows very good adsorption performance for the Acid Red G (azo dye). The adsorption equilibrium time was very short (within 30min) and the maximum adsorption capacity (Qmax) was 121.95 mg/g, which is better than that of some other adsorbents reported in literatures. The hierarchical structured PPy that we prepared can be considered as a potential adsorbent for the removal of organic dyes from wastewater.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Préparation, cinétique, thermodynamique, mécanisme et catalyseurs, Preparation, kinetics, thermodynamics, mechanism and catalysts, Polymères à propriétés spéciales, Polymers with particular properties, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Pharmacologie. Traitements medicamenteux, Pharmacology. Drug treatments, Pharmacologie générale, General pharmacology, Technologie pharmaceutique. Industrie pharmaceutique, Pharmaceutical technology. Pharmaceutical industry, Lactone copolymère, Lactone copolymer, Lactona copolímero, Acidolyse, Acidolysis, Acidolisis, Acrylique acide copolymère, Acrylic acid copolymer, Acrílico ácido copolímero, Antiinflammatoire non stéroïde, Non steroidal antiinflammatory agent, Antiinflamatorio no esteroide, Caprolactone copolymère, Caprolactone copolymer, Caprolactona copolímero, Cinétique, Kinetics, Cinética, Concentration critique micellaire, Micellar critical concentration, Concentración crítica micelar, Ethylène oxyde copolymère, Ethylene oxide copolymer, Etileno óxido copolímero, Etude expérimentale, Experimental study, Estudio experimental, In vitro, Libération, Release, Liberación, Modification chimique, Chemical modification, Modificación química, Nanoencapsulation, Nanoencapsulación, Naproxène, Naproxen, Naproxeno, Polymère amphiphile, Amphiphilic polymer, Polímero amfifilo, Polymère monodispersé, Monodispersed polymer, Polímero monodispersado, Polymère vecteur, Control release polymer, Polímero vector, Polymérisation ouverture cycle, Ring opening polymerization, Polimerización abertura ciclo, Polymérisation transfert atome, Atom transfer polymerization, Polimerización transferencia atomo, Polyélectrolyte, Polyelectrolyte, Polielectrolito, Préparation, Preparation, Preparación, Solution aqueuse, Aqueous solution, Solución acuosa, Solution micellaire, Micellar solution, Solución micelar, Spectre dimension, Dimension spectrum, Espectro dimensión, Terpolymère, Terpolymer, Terpolímero, Vecteur médicament, Drug carrier, Vector medicamento, pH, Acrylate de tert-butyle copolymère, Copolymère pentaséquencé, Atom transfer radical polymerization, Nanomicelles, Ring-opening polymerization, and pH-sensitive block copolymer

A series of poly(acrylic acid)-poly(ε-caprolactone)-poly(ethylene glycol)-poly(ε-caprolactone)-poly(acrylic acid) pH-sensitive PEG-[b-PCL-b-PAA]2 pentablock copolymers were synthesized via a combination of ring-opening polymerization (ROP), atom transfer radical polymerization (ATRP) and acidolysis. First, hydroxyl-terminated PEG (Mn = 4000 g mol-1) was used as starting material and stannous octanoate (Sn(Oct)2) as a catalyst for ROP of ε-caprolactone (CL). Then, the macroinitiator transformed from PEG-[b-PCL]2 (Mn = 13,700 and 21,800 g mol-1, by GPC) in high conversion initiated ATRPs of tert-butyl-acrylate (tBA) to construct PEG-[b-PCL-b-PtBA]2 (Mn = 17,000-26.000 g mol-1; Mw/ Mn = 1.13-1.25). Finally, the PEG-[b-PCL-b-PAA]2 was obtained via the acidolysis of the PtBA segment in PEG-[b-PCL-b-PtBA]2. The composition of triblock and pentablock copolymers was controlled by changing the feed ratios of CL/PEG in ROP and time in ATRP. The chain structures of copolymers were characterized by FT-IR, 1H NMR, and gel permeation chromatography (GPC). These copolymers are self-assembled into spherical nano size micelles in aqueous solution at pH < 4.5. The formation, size and morphology of nanomicelles were studied by scanning electron microscopy (SEM), dynamic light scattering (DLS) and by measuring the critical micelle concentration (CMC) using fluorescence spectroscopy. The loading and controlled release of naproxen as a model drug was investigated, and it was found that the total release in the buffer solution at pH 7.4 is higher than that at pH 4.2.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Physicochimie de surface, Surface physical chemistry, Matériaux adsorbants, Adsorbents, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Préparation, cinétique, thermodynamique, mécanisme et catalyseurs, Preparation, kinetics, thermodynamics, mechanism and catalysts, Polymères à propriétés spéciales, Polymers with particular properties, Acrylamide copolymère, Acrylamide copolymer, Acrilamida copolímero, Adsorbant organique, Organic adsorbent, Adsorbente orgánico, Adsorption liquide solide, Liquid solid adsorption, Adsorción líquido sólido, Agent surface cationique, Cationic surfactant, Agente superficie catiónico, Aire superficielle, Surface area, Area superficial, Cinétique, Kinetics, Cinética, Composé de l'ammonium quaternaire, Quaternary ammonium compound, Amonio cuaternario compuesto, Copolymère réticulé, Crosslinked copolymer, Copolímero reticulado, Copolymérisation radicalaire, Radical copolymerization, Copolimerización radical, Dimension pore, Pore size, Dimensión poro, Empreinte moléculaire, Molecular imprinting, Huella molecular, Etude expérimentale, Experimental study, Estudio experimental, Ion cuivre, Copper ion, Cobre ión, Ion métallique, Metal ion, Ión metálico, Isotherme adsorption, Adsorption isotherm, Isotermo adsorción, Matériau nanoporeux, Nanoporous materials, Milieu aqueux, Aqueous medium, Medio acuoso, Morphologie, Morphology, Morfología, Méthacrylate copolymère, Methacrylate copolymer, Metacrilato copolímero, Polymérisation sur matrice, Template polymerization, Polimerización sobre matriz, Préparation, Preparation, Preparación, Sélectivité ionique, Ionic selectivity, Selectividad iónica, pH, Diméthacrylate d'éthylène copolymère, Empreinte ionique, Adsorption studies, Cu2+, Hierarchically imprinted organic polymer, Isotherm, and Selectivity

A novel hierarchically imprinted cross-linked poly(acrylamide-co-ethylene glycol dimethacrylate) using a double-imprinting approach for the Cu2+ selective separation from aqueous medium was prepared. In the imprinting process, both Cu2+ ions and surfactant micelles (cetyltrimethylammonium bromide - CTAB) were employed as templates. The hierarchically imprinted organic polymer named (IIP-CTAB), single-imprinted (IIP-no CTAB) and non-imprinted (NIP-CTAB and NIP-no CTAB) polymers were characterized by SEM, FTIR, TG, elemental analysis and textural data from BET (Brunauer-Emmett-Teller) and BJH (Barrett-Joyner-Halenda). Compared to these materials, IIP-CTAB showed higher selectivity, specific surface area and adsorption capacity toward Cu2+ ions. Good selectivity for CU2+ was obtained for the Cu2+/Cd2+, Cu2+/Zn2+ and Cu2+/Co2+ systems when IIP-CTAB was compared to the single-imprinted (IIP-no CTAB) and non double-imprinted polymer (NIP-CTAB), thereby confirming the improvement in the polymer selectivity due to double-imprinting effect. For adsorption kinetic data, the best fit was provided with the pseudo-second-order model for the four materials, thereby indicating the chemical nature of the Cu2+ adsorption process. Cu2+ adsorption under equilibrium was found to follow dual-site Langmuir-Freundlich model isotherm, thus suggesting the existence of adsorption sites with low and high binding energy on the adsorbent surface. From column experiments 600 adsorption-desorption cycles using 1.8 mol L-1 HNO3 as eluent confirmed the great recoverability of adsorbent. The synthesis approach here investigated has been found to be very attractive for the designing of organic ion imprinted polymer and can be expanded to the other polymers to improve performance of ion imprinted polymers in the field of solid phase extraction.