16 research outputs found

    Particle Nucleation Using Different Initiators in the Miniemulsion Polymerization of Styrene

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    In miniemulsion polymerization, droplets nucleation is the key factor to ensure the production of polymer particles with a desired composition. The influence of the initiation on droplets nucleation is even conflicting and it has not been completely considered. The result of employing different initiators systems on the nucleation mechanism and kinetics in the polymerization of stable styrene/polystyrene miniemulsions with varied droplets size is here discussed. The employed initiation systems provide all combinations between the phase (aqueous or organic) where initiation mainly occurs and the phase affinity of the produced radicals. Latexes with different contribution of the droplets nucleation were synthesized according to the employed initiation system and the droplets size of the miniemulsion. The results here presented could be used as a guide for choosing the initiation system to achieve the required contribution of the droplets nucleation.Fil: Ronco, Ludmila Irene. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química (i); ArgentinaFil: Minari, Roque Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química (i); ArgentinaFil: Gugliotta, Luis Marcelino. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química (i); Argentin

    Acrylic-Casein Latexes with Potential Application as Adhesives

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    The replacement of monomers derived from petrochemical sources by biopolymers like proteins, together with the development of new materials with improved properties, have an increasing importance in industrial applications. In this context, the synthesis of acrylic-casein hybrid latexes was investigated through a low environmental impact strategy, such as the surfactant-free emulsion polymerization, with the aim of producing new industrial adhesives. Different aspects of the synthesis of hybrid latexes were addressed, such us i) the use of variable content of protein; ii) the control of grafting degree between polymers, using native casein (without chemical modification) or functionalized casein, and iii) the employment of a chain transfer agent to reduce molecular weights of the acrylic polymer. The effect of the analyzed variables on the polymerization kinetics, the degree of compatibility between polymers, and the application properties of the produced latexes as adhesives were investigated.Fil: Aguzin, Ana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Jerkovich, José Ignacio. Universidad Nacional del Litoral. Facultad de Ingeniería Química; ArgentinaFil: Trucone, Julieta. Universidad Nacional del Litoral. Facultad de Ingeniería Química; ArgentinaFil: Ronco, Ludmila Irene. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Roque Javier Minari. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Gugliotta, Luis Marcelino. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentin

    Proteins as promising biobased building blocks for preparing functional hybrid protein/synthetic polymer nanoparticles

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    The pursuit of sustainable and environmentally friendly materials has been powered by environmental concerns and the decline in oil reserves. Among the different routes toward this end, the replacement of oil-based materials by renewable materials stands out. In this way, protein based materials have gained interest. This review article summarizes the progress achieved in the synthesis of hybrid protein/synthetic polymer nanoparticles which have the potential to be used in industrial applications. Although technical achievements and efficacy proofs concerning the increased compatibility of polymer/protein are already available, practical implementation in industry still represents an additional challenge and should be the focus of interest in future research. The available literature supports the potential of hybrid protein/polymer nanoparticles in the production of ecofriendly alternatives for large scale applications as coatings, paints, adhesives and films.Fil: Cencha, Luisa Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Allasia, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Ronco, Ludmila Irene. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Luque, Gisela Carina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Picchio, Matías Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Minari, Roque Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Gugliotta, Luis Marcelino. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentin

    Temperature responsive PEG-based polyurethanes “ a la carte”

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    Temperature responsive polymers able to alter their chemical or physical properties have been extensively investigated. Most of these polymers have an alkane polymer backbone with only carbon-carbon bonds. In this sense, the design of thermoresponsive polymers not only with sharp transition temperatures but also possessing hydrolizable linkages such as esters, carbonates or urethanes in the main backbone are highly desired. Here we show a library of thermoresponsive cationic and anionic polyurethanes synthesized by copolymerization of isophorone diisocyanate with poly(ethylene glycol) and ionic diols. These polyurethanes exhibit lower critical solution temperatures (LCST) that can be easily tuned from 20 C to 60 C by altering the polyurethane composition. Our findings show that LCST temperature could be reduced by the using poly(ethylene glycol) of lower molecular weight and/or increasing the hydrophobicity of the employed ionic diol. We also demonstrated that the thermoresponsive behavior could be translated to hydrogels based on those ionic polyurethanes. These “a la carte” thermoresponsive polyurethanes materials present a great potential in the biomedical field due to the presence of hydrolizable linkages in the main polymer backboneThe authors would like to thank the European Commission for their financial support through the project SUSPOL-EJD 642671 and the Gobierno Vasco/Eusko Jaurlaritza (Grant IT999-16). Ludmila I. Ronco thanks to the European Project IRSES-IONRUN and CONICET of Argentina for the financial support of her stay in Spain

    Biobased supramolecular ionic networks with optimized crystallinity and mechanical properties as promising dynamic materials for eutectogels design

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    Ionic supramolecular networks are attractive materials for technological applications with unique properties such as ionic conductivity, stimuli-responsiveness, recyclability, and self-healing. Herein, new semicrystalline supramolecular ionic networks are designed from fully biobased building blocks such as tartaric acid, phytic acid, sebacic acid, and a fatty dimer diamine (Priamine™ 1071). The combination of tartaric acid with Priamine™ 1071 results in a crystalline and brittle polymer, but its molecular regularity can be controlled by incorporating sebacic acid or phytic acid, affording tough materials with appropriate mechanical properties (elastic moduli ranging 19–42 MPa). Furthermore, the ionic polymers show network-to-liquid phase transitions between 75 and 127 °C, and in the liquid state, they were found to be miscible with a lithium-based deep eutectic solvent, yielding flexible and conductive eutectogels. Altogether, these dynamic networks could open new prospects for developing fully green soft ionic materials from their combination with other innovative and low-cost eutectic mixtures.Open Access funding provided by the University of Basque Country. The financial support received from CONICET and ANPCyT (PICT 2018-01032) (Argentina) is gratefully acknowledged

    Crosslinked casein micelles bound paclitaxel as enzyme activated intracellular drug delivery systems for cancer therapy

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    Nanomedicine for cancer therapy is a successful tool to diminish the side effect of chemotherapeutics such as paclitaxel (PTX). In this regard, Abraxane®, a human serum albumin (HSA)-based nanomedicine system has shown lesser side effects than Taxol®. However, the large-scale production of HSA protein is limited and expensive, which is traduced in a high cost of the treatments in clinical applications. Thus, the use of easily-available alternative nanocarriers could increment the accessibility of patients to nanomedicine for cancer treatments. Casein is a low-cost protein able to self-assemble into micelles which could efficiently encapsulate PTX into their structure. In this work, the synthesis of chemically crosslinked casein micelles (CCM), used to prepare PTX-based nanoformulations, is presented. CCM@PTX nanoformulations showed promising results in vitro to be applied as nanomedicine for cancer therapy. Thus, the obtained nanoformulations are great candidates to be parenterally administered, accumulate in tumor by passive targeting without leakage of PTX in plasma, and release the drug within the tumor microenvironment, in response to overexpressed proteases such as trypsin.Fil: Cuggino, Julio César. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Picchio, Matías Luis. Universidad Nacional de Córdoba. Instituto de Investigación y Desarrollo en Ingeniería de Procesos y Química Aplicada. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación y Desarrollo en Ingeniería de Procesos y Química Aplicada; ArgentinaFil: Gugliotta, Agustina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bürgi Fissolo, María de Los Milagros. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ronco, Ludmila Irene. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Calderón, Marcelo. Polymat; EspañaFil: Etcheverrigaray, Marina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; ArgentinaFil: Alvarez Igarzabal, Cecilia Ines. Universidad Nacional de Córdoba. Instituto de Investigación y Desarrollo en Ingeniería de Procesos y Química Aplicada. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación y Desarrollo en Ingeniería de Procesos y Química Aplicada; ArgentinaFil: Minari, Roque Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Gugliotta, Luis Marcelino. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentin

    Production of hybrid polystyrene/polybutadiene nanoparticles with low environmental impact by miniemulsion polymerization

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    Fil: Ronco, Ludmila Irene. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Argentina.En este trabajo de tesis se investiga la síntesis de nanopartículas híbridas de poliestireno/polibutadieno, con nanoestructura controlada y bajo contenido de compuestos orgánicos volátiles (VOCs), para su potencial aplicación en plásticos nanoestructurados reforzados, mediante un proceso de bajo impacto medio ambiental como lo es la polimerización en miniemulsión. Para esto, se abordaron problemas ligados a la síntesis como: i) el empleo de diferentes sistemas de iniciación y el estudio de su influencia sobre la cinética de polimerización y la nucleación de partículas; ii) la polimerización con altos contenidos de sólidos para que el proceso resulte de interés industrial; iii) la reducción del monómero residual en los látex mediante diferentes alternativas de post-polimerización, para obtener un producto con bajo contenido de VOCs; y iv) la influencia de las condiciones de polimerización y post-tratamiento sobre la microestructura del polímero, y la morfología de las partículas híbridas en el látex. Finalmente, se realizó un estudio preliminar del desempeño de los principales materiales sintetizados en cuanto a sus propiedades macroscópicas, considerándose su relación con la microestructura y la morfología de las nanopartículas, controladas en el proceso de síntesis.This Thesis presents the synthesis of hybrid polystyrene / polybutadiene latexes through a low environmental impact process, such as the miniemulsion polymerization, with the aim of obtaining nanoparticles with controlled nanostructure, low content of volatile organic compounds (VOCs), and with potential applications as reinforced materials. Different aspects related to the considered process were addressed: i) the use of different initiation systems, studying their influence on the polymerization kinetics and particle nucleation; ii) the polymerization with high solids, that increase the industrial interest of the proposed process; iii) the reduction of the residual monomer in the latexes by different post-polymerization methods, obtaining a product with low content of VOCs; and iv) the influence of polymerization and post-polymerization conditions on the polymer microstructure and nanoparticles morphology. Finally, a preliminary study of macroscopic properties of the main synthesized materials was also presented, considering its relationship with the polymer microstructure and the nanoparticles morphology, controlled during the synthesis.Consejo Nacional de Investigaciones Científicas y TécnicasAgencia Nacional de Promoción Científica y Tecnológic

    Emulsion Polymerization of MMA employing a Chain Transfer Agent of Low Environmental Impact: Iso-Octyl-3- Mercaptopropionate

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    The unseeded batch-emulsion polymerisation of methyl methacrylate (MMA) was investigated using the chain transfer agent iso-octyl-3- mercaptopropionate (iOMP), which exhibits a low environmental impact. The commercial iOMP is a mixture of over 10 isomers that proved adequate to control the molecular weights of poly(methyl methacrylate) with a decreasing evolution of both the number- and weight-average molecular weights along the reactions. The iOMP also affects the polymerisation kinetics as a consequence of the lower reactivity of the iOMP radicals with respect to the MMA-ended radicals. Experimental results were interpreted with the help of a first principles mathematical model.Fil: Ronco, Ludmila Irene. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico Para la Industria Química (i); ArgentinaFil: Minari, Roque Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico Para la Industria Química (i); ArgentinaFil: Cian, Lorena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química (i); ArgentinaFil: Vega, Jorge Ruben. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico Para la Industria Química (i); Argentina. Universidad Tecnologica Nacional; ArgentinaFil: Gugliotta, Luis Marcelino. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico Para la Industria Química (i); Argentin

    Molar mass distributions in homopolymer blends from multimodal chromatograms obtained by Sec/Gpc with a concentration detector

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    This article proposes data treatment for estimating the individual (and unimodal) molar mass distributions (MMDs) of each polymer component in a blend from multimodal concentration chromatograms obtained by size exclusion chromatography (SEC/GPC). The Differential Refractometer (DR) chromatograms are deconvoluted into linear combinations of exponentially-modified Gaussian distributions. The deconvolutions are possible if the individual peaks are not fully overlapped and if the mass fractions of the minor components are not too low. To help determine the number and approximate location of the individual peaks, the second derivative of the chromatogram is employed. For blends of chemically identical homopolymers, the deconvolution stage directly provides the mass fractions of the individual peaks. For blends of two chemically different homopolymers, the chemical composition and detector responses of the individual components must be determined, for example with the help of dual detection (UV/DR). The procedure was validated with blends of a priori known componentsFil: Clementi, Luis Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico Para la Industria Química (i); Argentina. Universidad Tecnologica Nacional; ArgentinaFil: Meira, Gregorio Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico Para la Industria Química (i); ArgentinaFil: Berek, Dusan. Universidad Tecnológica Nacional. Facultad Regional Santa Fe; ArgentinaFil: Ronco, Ludmila Irene. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química (i); ArgentinaFil: Vega, Jorge Ruben. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico Para la Industria Química (i); Argentina. Universidad Tecnologica Nacional; Argentin

    Incorporation of Polybutadiene into Waterborne Polystyrene Nanoparticles via Miniemulsion Polymerization

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    The incorporation of polybutadiene in waterborne polystyrene nanoparticles by miniemulsion polymerization is expected to positively combine the properties of both materials,improving the impact resistance and toughness. The kinetics of the miniemulsion polymerization used to synthesize these hybrid nanomaterials and the effect of the reaction variables on the polymer microstructure and particle morphology were investigated. Both molecular microstructure and final particle morphology (core?shell, ??salami?? or threephase type) depended on the nature of the employed polybutadiene based rubbers and initiators. The mechanisms responsible for these effects were discussed.Fil: Ronco, Ludmila Irene. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico Para la Industria Química (i); ArgentinaFil: Minari, Roque Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico Para la Industria Química (i); ArgentinaFil: Vega, Jorge Ruben. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico Para la Industria Química (i); Argentina. Universidad Tecnologica Nacional; ArgentinaFil: Meira, Gregorio Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico Para la Industria Química (i); ArgentinaFil: Gugliotta, Luis Marcelino. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico Para la Industria Química (i); Argentin
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