Elena Gabirondo

Developing sustainable strategies for the lucrative application of biopolymers is crucial for advancing environmentally friendly materials. Ethyl cellulose, a water-insoluble and biocompatible polysaccharide with excellent mechanical and thermal stability, is a promising material for membrane technology. This study explores nonionic, alcohol-based hydrophobic natural deep eutectic solvents (DES) as green additives for ethyl cellulose membranes. Spectroscopic analyses confirmed the successful incorporation of DES, supported by Hansen solubility parameter predictions indicating dispersive and hydrogen-bonding interactions as key mechanisms. The incorporation of DES markedly enhanced the flexibility of the polymer, lowering the glass transition temperature from 98 °C to below 0 °C. Barrier studies demonstrated that the addition of DES decreased the water vapor permeability and single-gas permeabilities (N₂, CO₂, and O₂) without compromising gas selectivity. Moreover, the Eco-Scale assessment classified the membrane fabrication method as green, confirming improvements in sustainability metrics. Overall, hydrophobic DES are versatile and environmentally benign additives that simultaneously enable the tailoring of mechanical properties and improvement of barrier performance in ethyl cellulose membranes.

The use of electro‐electrodialysis (EED) for the conversion of lithium salts obtained from either hard‐rock minerals or brines into high‐value battery‐grade lithium hydroxide is gaining traction as an alternative green technology. Current cation exchange membranes employed in Li‐salt EED possess low selectivity towards Li ⁺ and are dominated by polyfluoroalkyl polymer‐based membranes, which pose significant environmental concerns. Hence, there is a need for the development of inexpensive membranes for Li‐salt EED applications with a lower content of environmentally hazardous fluorinated compounds. In this work, novel self‐standing Li‐selective and low‐fluorine content membranes have been developed based on inexpensive methacrylic monomers, including a lithium sulfonyl‐1‐(trifluoromethylsulfonyl)imide monomer. The membranes were prepared via fast UV‐photopolymerisation. Rational design of the membranes with different co‐monomer compositions and crosslinking degrees enabled the tailoring of the membrane properties including water uptake, mechanical strength, and electrochemical performance. The membranes showed a high Li‐ion conductivity of up to 6.2 mS cm ⁻¹ and comparable EED performance to that of the Nafion117 membrane as benchmark, i.e., relatively low energy consumption of 13.9 kWh kg ⁻¹ _LiOH and high molar flux of up to 3.9 mmol h ⁻¹ , with a Li ⁺ /Na ⁺ molar fluxes ratio of 0.98.

Plastikoen ekoizpena eta kontsumoa etengabe handitzen ari da, eta horrek ingurumen-arazo larriak eragiten ditu. Testuinguru horretan, polimero jasangarri eta zirkularren garapena funtsezkoa da trantsizio ekologikoan aurrera egiteko. Lan honek poliesterretan jartzen du arreta, bi arrazoirengatik: batetik, haien erabilera zabalagatik (PET, PLA, PEF...), eta, bestetik, egitura hidrolizagarriak izateak birziklapen kimikorako aukera ematen duelako. Poliester jasangarriak bi ikuspegitatik aztertzen dira: lehengai berriztagarrietatik abiatutako sintesia, eta bizi-zikloaren amaierako degradagarritasuna eta birziklagarritasuna. Bereziki, birziklapen kimikoak, polimeroa bere monomeroetan edo beste produktu baliotsu batzuetan banatzeko prozesuak, ­aukera ematen du polimero horiek kalitatea galdu gabe berrerabiltzeko. Hidrolisia, glikolisia edo metanolisia bezalako metodoak aztertzen dira, baita horien eraginkortasuna eta eskalagarritasuna ere. Azkenik, lanak jasangarritasunaren ikuspegi orokorra ematen du: karbono-aztarna, baliabide fosilen murrizketa, eta zirkulartasun-printzipioak kontuan hartuz. Lan honen helburua poliesterren jasangarriagoak sortzeko bideak identifikatzea da, ekonomiaren eta ingurumenaren arteko oreka bilatuz.

Atmospheric water harvesting (AWH) is an emerging technology for collecting water from fog and humidity. We propose a novel thermoresponsive hydrogel polymer network coupled with organic transparent heater for AWH and voltage controlled release.

Taurine has the ability to promote the selective chemical recycling of polyhydroxybutyrate into high-value hydroxy acid.

Photoactive films made from poly(3-hexylthiophene)- graft -poly(ε-caprolactone) copolymers with tunable nanostructured morphologies through thermo-oxidation, modulating reactive oxygen species (ROS) generation upon photostimulation.

The development of new sustainable polymeric materials endowed with improved performances but minimal environmental impact is a major concern, with polyesters as primary targets. Lactones are key monomers thanks to ring-opening polymerization, but their use in step-growth polymerization has remained scarce and challenging. Herein, we report a powerful bis(γ-lactone) (γSL) that was efficiently prepared on a gram scale from malonic acid by Pd-catalyzed cycloisomerization. The γ-exomethylene moieties and the spiro structure greatly enhance its reactivity toward ring-opening and enable step-growth polymerization under mild conditions. Using diols, dithiols, or diamines as comonomers, a variety of regioregular (AB)_n copolymers with diverse linkages and functional groups (from oxo-ester to β-thioether lactone and β-hydroxy-lactame) have been readily prepared. Reaction modeling and monitoring revealed the occurrence of an original trans-lactonization process following the first ring-opening of γSL. This peculiar reactivity opens the way to regioregular (ABAC)_n terpolymers, as illustrated by the successive step-growth polymerization of γSL with a diol and a diamine.

Producing backbone degradable copolymers via free-radical copolymerization is a promising, yet challenging method to develop more sustainable materials for many applications. In this work, we present the copolymerization of 2-methylen-1,3-dioxepane (MDO) with crotonic acid derivative esters. MDO can copolymerize by radical ring-opening polymerization incorporating degradable ester moieties in the polymer backbone, although this can often be difficult due to the very unfavorable reactivity ratios. Crotonic acid derivatives, on the other hand, can be easily produced completely from biomass but are typically very difficult to (co)polymerize due to low propagation rates and very unfavorable reactivity ratios. Herein, we present the surprisingly easy copolymerization between MDO and butyl crotonate (BCr), which shows the ability to form alternating copolymers. The alternating nature of the copolymer was characterized by MALDI-TOF and supported by the reactivity ratios calculated experimentally (r_MDO = 0.105 and r_BCr = 0.017). The alternating nature of the copolymers favored the degradability that could be achieved under basic conditions (in 2 h, all chains have molar masses smaller than 2 kg/mol). Last, the work was expanded to other crotonate monomers to expand the portfolio and show the potential of this copolymer family.