Poly(diallylmethylammonium) proton conducting membranes with high ionic conductivity at intermediate temperatures

High temperature proton exchange membrane fuel cells are being lately investigated because of their high energy efficiency, their superior heat/water management, CO tolerance, and electrode reaction kinetics. To further advance this technology, the polymer membrane portfolio and performance should be improved for intermediate or high temperature operation (>100 °C). In this work we present new poly(diallylmethylammonium) proton conducting membranes with high ionic conductivity at 120 °C. First, new protic ionic liquids, hereafter called DAMAH+X−, were synthesized leading to diallylmethylammonium monomers with different counter-anions. By radical cyclopolymerization through thermal and photoinitiation mechanisms, self-standing protic polymeric membranes of poly(diallylmethylammonium X−) were obtained. Membranes showed good thermal stability (>250 °C) and mechanical properties without the need of additives such as (protic) ionic liquids, solvents or inorganic charges. Great attention was paid to understand the effect of the different counter-anions on the membrane properties. As a general trend, fluorinated anions coming from strong acids confer high ionic conductivity and allow to reduce the hygroscopic properties on the protic polymeric membranes. Proton structural and dynamical stability at different temperatures and humidification conditions were investigated by Neutron Scattering (QENS and NR). The optimized poly(diallylmethylammonium X−) shows similar ionic conductivity values than Nafion 212 under varying relative humidity conditions at 80 °C. Furthermore, it shows a high ionic conductivity value of 1.9 × 10−3 S cm−1 at 120 °C under dry conditions

Easy-to-Make Polymer Hydrogels by UV-Curing for the Cleaning of Acrylic Emulsion Paint Films

The cleaning of acrylic emulsion paint surfaces poses a great challenge in the conservation field, due to their high water sensitivity. In this article, we present easy-to-make polymer hydrogels, made by UV-photopolymerization, that show excellent cleaning properties. The formulation of hydrogels obtained by UV-curing and their performance as dry cleaners for acrylic paints was investigated. First, different hydrogel formulations based on functional acrylic monomers were used to formulate a series of UV cross-linked hydrogels by fast UV photopolymerization. Their effectiveness on surface dirt removal was investigated by SEM microscopy and colorimetry. The hydrogels showed excellent cleaning properties and controlled water release, and they still performed satisfactorily after several cleaning uses. The obtained UV-hydrogels were compared to the well-known agar gels, showing benefits in terms of reducing excess water. This article shows that easy-to-make UV-cured hydrogels are an efficient tool for the cleaning of surface dirt from water-sensitive paintings, overcoming the limits of traditional cleaning methods.This research was funded by European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie Grant Agreement No. 797295 (eJUMP)

Catechol-Containing acrylic poly(ionic liquid) hydrogels as bioinspired Filters for Water decontamination

Mussel inspired catechol containing materials have currently drawn great attention as biomaterials, adhesives, surface coatings and in bioelectronics, among other applications. In this work, we mimicked the ability of mussels as water filtration systems to adsorb organic and inorganic contaminants. For this purpose, the synthesis of biomimetic hydrogels by co-polymerization of a new ionic monomer, dopamine methacrylic acid salt (iDA) with a series of water soluble methacrylate monomers was performed using visible light photopolymerization. The iDA ionic monomer is highly water soluble as compared to previous reported monomers containing catechol groups. This allows its incorporation into different acrylic hydrogels in concentrations up to 50 % mol of monomers containing catechol groups, leading to functional materials with variable morphology and swelling properties. The hydrogels displayed to be highly effective for the removal of heavy metals such as As(V) and Cr(VI) with very good effectiveness compared to other commonly employed natural sorbents, such as clays. Additionally, these poly(ionic liquid) hydrogels containing catechol groups were evaluated in the removal also of other pollutants such as charged organic dyes. Preliminarily results demonstrate the versatility of these materials that combine catechol and ionic chemistry for the adsorption of a wide variety of water pollutants.Fil: Gallastegui, Antonela. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados; ArgentinaFil: Porcarelli, Luca. Polymat University Of The Basque ; EspañaFil: Palacios, Rodrigo Emiliano. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados; ArgentinaFil: Soulé Gómez, María Lorena. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados; ArgentinaFil: Mecerreyes Molero, David. Polymat University Of The Basque ; Españ

Aging Effect of Catechol Redox Polymer Nanoparticles for Hybrid Supercapacitors

[EN] Redox-polymer nanoparticles are a promising solution to avoid the detrimental dissolution of organic electrode materials while showing discrete redox processes. In this work, catechol-based redox-active polymer nanoparticles (cRPNs) were synthesized through one-step emulsion polymerization with a tunable size from 25 to 150 nm. The fresh cRPNs were characterized and showed a reversible redox process centered at 0.50 V (vs. Ag/AgCl) in 1 M H2SO4. Unexpectedly, the cRPN latex aged after days passing from white to pink. This aging resulted in a shift of its redox potential toward higher values, which could be associated to autoxidation of the catechol groups and subsequent crosslinking of NPs due to catechol dimer formation. Finally, we compared the performance of fresh and aged cRPNs in a hybrid supercapacitor device, proving how the aging effect had some benefits such as an increase in the voltage output, specific capacitance, cyclability and Coulombic efficiencies of the device.The authors thank for technical and human support provided by IZO-SGI SGIker of UPV/EHU. Technical and human support provided by IZO-SGI, SGIker (UPV/EHU, MICINN, GV/EJ, ERDF and ESF) is gratefully acknowledged for assistance and generous allocation of computational resources. The authors would like to thank the European Commission for financial support through funding from the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No 823989. N.P. appreciates Spanish MINECO for the Juan de la Cierva-formation fellowship (FJC2018-037781-I). R.M. thanks the Spanish Ministry of Science, Innovation and Universities through the SUSBAT project (Ref.RTI2018-101049-B-I00) (MINECO/FEDER, UE) for financial support

Fast Visible-Light Photopolymerization in the Presence of Multiwalled Carbon Nanotubes: Toward 3D Printing Conducting Nanocomposites

[EN] A new photoinitiator system (PIS) based on riboflavin (Rf), triethanolamine, and multiwalled carbon nanobutes (MWCNTs) is presented for visible-light-induced photopolymerization of acrylic monomers. Using this PIS, photopolymerization of acrylamide and other acrylic monomers was quantitative in seconds. The intervention mechanism of CNTs in the PIS was studied deeply, proposing a surface interaction of MWCNTs with Rf which favors the radical generation and the initiation step. As a result, polyacrylamide/MWCNT hydrogel nanocomposites could be obtained with varying amounts of CNTs showing excellent mechanical, thermal, and electrical properties. The presence of the MWCNTs negatively influences the swelling properties of the hydrogel but significantly improves its mechanical properties (Young modulus values) and electric conductivity. The new PIS was tested for 3D printing in a LCD 3D printer. Due to the fast polymerizations, 3D-printed objects based on the conductive polyacrylamide/CNT nanocomposites could be manufactured in minutes.The authors are thankful for technical and human support provided by IZO-SGI SGIker of UPV/EHU. The authors would like to thank the European Commission for financial support through funding from the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement no. 823989

Multifunctional Ionic Polymers from Deep Eutectic Monomers Based on Polyphenols

Herein we report a novel family of deep eutectic monomers and the corresponding polymers, made of (meth)acrylic ammonium salts and a series of biobased polyphenols bearing catechol or pyrogallol motifs. Phenolic chemistry allows modulating molecular interactions by tuning the ionic polymer properties from soft adhesive to tough materials. For instance, pyrogallol and hydrocaffeic acid-derived ionic polymers showed outstanding adhesiveness (>1 MPa), while tannic acid/gallic acid polymers with dense hydrogen bond distribution afforded ultratough elastomers (stretchability ≈1000% and strength ≈3 MPa). Additionally, phenolic polymeric deep eutectic solvents (polyDES) featured metal complexation ability, antibacterial properties, and fast processability by digital light 3D printing.This work was supported by Marie Sklodowska-Curie Research and Innovation Staff Exchanges (RISE) under grant agreement no. 823989 “IONBIKE”. The financial support from CONICET and ANPCyT (PICT 2018-01032) (Argentina) is also gratefully acknowledged

Mixed Ionic and Electronic Conducting Eutectogels for 3D-Printable Wearable Sensors and Bioelectrodes

Eutectogels are a new class of soft ion conductive materials that are attracting attention as an alternative to conventional hydrogels and costly ionic liquid gels to build wearable sensors and bioelectrodes. Herein, the first example of mixed ionic and electronic conductive eutectogels showing high adhesion, flexibility, nonvolatility, and reversible low-temperature gel transition for 3D printing manufacturing is reporting. The eutectogels consist of choline chloride/glycerol deep eutectic solvent, poly(3,4-ethylenedioxythiophene): lignin sulfonate, and gelatin as the biocompatible polymer matrix. These soft materials are flexible and stretchable, show high ionic and electronic conductivities of 7.3 and 8.7 mS cm−1, respectively, and have high adhesion energy. Due to this unique combination of properties, they could be applied as strain sensors to precisely detect physical movements. Furthermore, these soft mixed ionic electronic conductors possess excellent capacity as conformal electrodes to record epidermal physiological signals, such as electrocardiograms and electromyograms, over a long time.M.L.P. and A.G. contributed equally to this work. This work was supported by Marie Sklodowska-Curie Research and Innovation Staff Exchanges (RISE) under the grant agreement No 823989 “IONBIKE.” The financial support received from CONICET and ANPCyT (Argentina) is also gratefully acknowledged. Thanks to the Flexible Electronic Department (FEL) of Ecole des Mines de Saint-Etienne (EMSE) for the combined mechanical/electrical characterization

New bifunctional cross-linkers / co-initiators for vinyl photopolymerization: Silsesquioxanes - B2 vitamin as eco-friendly hybrid photoinitiator systems

The development of new and improved aqueous soluble cross-linkers and eco-friendly co-initiators for photopolymerization applications represents a significant challenge. In this work, novel water-soluble eco-friendly hybrid photoinitiator systems were prepared and characterized. The developed photoinitiators consist of hybrid compounds based on silsesquioxanes, functionalized with acrylate and amine groups with dual capacity as co-initiators and cross-linkers; and B2 vitamin (riboflavin) that performs as a biocompatible photosensitizer. The materials were characterized by FTIR, MALDI-TOF MS, and 29Si-NMR. The efficiency of co-initiators in photopolymerization was evaluated monitoring C[dbnd]C conversion using FTIR as a function of irradiation time. The photoinitiator systems showed different polymerization rates depending on the employed silsesquioxane. Polymerization rates of the new photoinitiator systems are higher than that of a reference system based on riboflavin/triethanolamine. Hydrogels and nanogels were successfully synthesized, demonstrating the versatility of the developed photoinitiators.Fil: Gallastegui, Antonela. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados; Argentina. Universidad del País Vasco. Polymat; EspañaFil: Zambroni, Maria Emilia. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados; ArgentinaFil: Chesta, Carlos Alberto. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados; ArgentinaFil: Palacios, Rodrigo Emiliano. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados; ArgentinaFil: Gomez, María Lorena. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados; Argentin

Controlled release of antibiotics from photopolymerized hydrogels: Kinetics and microbiological studies

The development of convenient synthetic methods and improved materials for the production of high load-capacity and biocompatible drug delivery systems is a challenging task with important implications in health sciences. In this work, acrylamide/2-hydroxyethylmethacrylate and N-isopropylacrylamide/2-hydroxyethylmethacrylate hydrogels were synthesized by photopolymerization using energy-efficient green-LEDs. A functionalized silsesquioxane was used as both crosslinker and co-initiator for the photopolymerization. The hybrid organic-inorganic nature of the silsesquioxane improved the resulting hydrogels´ properties increasing their swelling capacity and biocompatibility. Additionally, the mild conditions used during the photopolymerization allowed the synthesis of hydrogels in the presence of antibiotics yielding high load-capacity materials in which the drug preserves its molecular structure and antimicrobial activity (as confirmed by HPLC and microbiological assays). The materials were characterized by FTIR, DSC and SEM. Additionally, the kinetics of gels´ swelling and drug release were studied under physiological conditions (pH 7.4 and 37 °C). The results demonstrate how hydrogel composition affects the antibiotics-release kinetics. The final drug release percentage increased with increasing molar fraction of acrylamide or N-isopropylacrylamide and in most cases exceeded 85%. Finally, the antibacterial effect of loaded gels was characterized using a number of assays against Gram negative and Gram positive bacteria. The observed antibacterial effect correlated well with swelling and drug release results. Furthermore, gels are not toxic for isolated erythrocytes as demonstrated by haemolytic tests. Overall, our results indicate that the produced hydrogels are promising materials to develop controlled drug-delivery devices such as capsules, dermatological patches and others.Fil: Gallastegui, Antonela. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados; ArgentinaFil: Spesia, Mariana Belen. Universidad Nacional de Río Cuarto. Instituto para el Desarrollo Agroindustrial y de la Salud. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto para el Desarrollo Agroindustrial y de la Salud; ArgentinaFil: Dell'Erba, Ignacio Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Chesta, Carlos Alberto. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados; ArgentinaFil: Previtali, Carlos Mario. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Palacios, Rodrigo Emiliano. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados; ArgentinaFil: Gomez, María Lorena. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados; Argentin

Multifunctional Ionic Polymers from Deep Eutectic Monomers Based on Polyphenols

Herein we report a novel family of deep eutectic monomers and the corresponding polymers, made of (meth)acrylic ammonium salts and a series of biobased polyphenols bearing catechol or pyrogallol motifs. Phenolic chemistry allows modulating molecular interactions by tuning the ionic polymer properties from soft adhesive to tough materials. For instance, pyrogallol and hydrocaffeic acid-derived ionic polymers showed outstanding adhesiveness (>1 MPa), while tannic acid/gallic acid polymers with dense hydrogen bond distribution afforded ultratough elastomers (stretchability ≈1000% and strength ≈3 MPa). Additionally, phenolic polymeric deep eutectic solvents (polyDES) featured metal complexation ability, antibacterial properties, and fast processability by digital light 3D printing.Fil: López de Lacalle, Jon. Universidad del País Vasco; EspañaFil: Gallastegui, Antonela. Universidad del País Vasco; España. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Olmedo Martínez, Jorge L.. Universidad del País Vasco; EspañaFil: Moya, Melissa. Universidad de Ciencias Médicas; Costa RicaFil: Lopez Larrea, Naroa. Universidad del País Vasco; EspañaFil: 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; Argentina. Universidad del País Vasco; EspañaFil: Mecerreyes, David. Universidad del País Vasco; Españ