Search Results (212)

Conventional anticorrosive coatings suffer from limitations of low solid content and rigorous surface pretreatment, posing environmental and cost challenges in field applications. In this study, a novel high-solid-content (>95%) epoxy-polysiloxane (Ep-PSA) ceramic metal coating was prepared that enables low-surface-treatment application. The originality lies in the synergistic combination of nano-sized ceramic powders, high-strength metallic powders, polysiloxane resin (PSA), and solvent-free epoxy resin (Ep), which polymerize through an organic–inorganic interpenetrating network to form a dense shielding layer. The as-prepared Ep-PSA coating system chemically bonds with indigenous metal substrate via Zn₃(PO₄)₂ and resin functionalities during curing, forming a conversion layer that reduces surface preparation requirements. Differentiating from existing high-solid coatings, this approach achieves superior long-term barrier properties, evidenced by |Z|_0.01Hz value of 9.64 × 10⁸ Ω·cm², after 6000 h salt spray exposure—four orders of magnitude higher than commercial 60% epoxy zinc-rich coatings (2.26 × 10⁴ Ω·cm², 3000 h salt spray exposure). The coating exhibits excellent adhesion (14.28 MPa) to standard sandblasted steel plates. This environmentally friendly, durable, and easily applicable composite coating demonstrates significant field application value for large-scale energy infrastructure. Full article

In recent years, the unsustainable consumption of fossil resources has been causing major ecological concerns, especially for the production of polymeric materials. 2,5-furandicarboxylic acid (FDCA) is one of the most appealing biobased chemical building blocks, because of its potential to replace the industrially widespread petrochemical, terephthalic acid. Camphoric acid (CA) is also an interesting biobased chemical derived from camphor, one of the most widespread fragrances. This work had the objective of combining CA, FDCA and biobased 1,6-hexanediol to synthesize random copolymers for sustainable food packaging applications by means of a solvent-free polycondensation process, obtaining poly(hexamethylene furanoate-co-camphorate)s (PHFC). The optimization of the synthesis made it possible to obtain high molecular weight polyesters with a percentage of camphoric acid up to 17 mol%, which could be compression-molded into films. They were subjected to molecular, structural, thermal and functional characterization via NMR, GPC, WAXS, DSC, and TGA analyses, as well as mechanical and gas permeability tests. Compared to the homopolymer of reference, it was possible to obtain higher flexibility, 430% higher elongation at break, and 223% higher toughness, with comparable, excellent gas permeability properties. Calorimetric evidence suggested that camphoric acid might have enhanced the formation of a partially ordered mesomorph phase in the copolymers under study. Full article

Driven by environmental concerns, the packaging industry is shifting toward high-performance and bio-based coating alternatives. In this research, poly(methylmethacrylate) (PMMA) and modified cellulose nanocrystal (m-CNC) were employed as reinforcing agents to develop sustainable poly (lactic acid)-based coatings for packaging applications. Various formulations, influenced by polymer matrix blends and m-CNC loadings (1–5%), were prepared using solvent and applied as protective coating on cardboard paper substrates. The grammage of polymeric coatings (CG) on paper was also investigated using various wet film thicknesses (i.e., 150–250 μm). Accordingly, key parameters including water contact angle, thermal behavior, mechanical performances and barrier properties were systematically evaluated to assess the effectiveness of the developed nanocomposite coatings. As a result, nonylphenol ethoxylate surfactant-modified cellulose nanocrystals exhibited good dispersion and stable suspension in chloroform for one hour, improving compatibility and interaction of polymer–CNC fillers. The water vapor permeability (WVP) of PLA-coated papers was significantly reduced by blending PMMA and increasing the content of m-CNC nanofillers. Furthermore, CNC incorporation enhanced the oil resistance of PLA/PMMA-coated cardboard. Pronounced improvements in barrier properties were observed for paper substrates coated with dry coat weight or CG of ~20 g/m² (corresponding to 250 μm wet film thickness). Coatings based on blended polymer—particularly those reinforced with nanofillers—markedly enhanced the hydrophobicity of the cardboard papers. SEM-microscopy confirmed the structural integrity and morphology of the nanocomposite coatings. Regarding mechanical properties, the upgraded nanocomposite copolymer (PLA-75%/PMMA-25%/m-CNC3%) exhibited the highest bending test and tensile strength, achieved on coated papers and free-standing polymeric films, respectively. Based on DSC analysis, the thermal characteristics of the PLA matrix were influenced to some extent by the presence of PMMA and m-CNC. Overall, PLA/PMMA blends with an optimal amount of CNC nanofillers offer promising sustainable coatings for the packaging applications. Full article

Polyelectrolyte microspheres based on a polymer containing sulfonate groups are considered promising drug delivery systems for encapsulating drugs and ensuring their prolonged release. In this study, gel microparticles based on various sulfonate-containing polymers were formed, and their potential as drug delivery systems was evaluated, particularly for the controlled administration of the cytotoxic anthracycline antibiotic doxorubicin and the antifungal drug fuchsine. An undeniable advantage of such gel microspheres is the presence in their structure of sulfonate groups localized both in the surface layer and in the volume. The main monomers used were styrene-4-sulfonic acid sodium salt and 3-sulfopropyl methacrylate potassium salt; spherical, porous microparticles were obtained via free-radical reverse suspension polymerization. Microsphere properties (size, porosity, pore structure, electrical surface properties, and swelling) were tailored by changing the nature of the sulfonate, using a comonomer (vinyl acetate or ethyl acrylate), adding a co-solvent, or modulating the crosslinker composition, which influenced drug loading efficiency (doxorubicin, fuchsine). The gel-like structure of the microspheres was confirmed, and the sulfonate groups were found to be distributed throughout both the surface layer and the internal volume of the microspheres. A comparison was also made with non-porous polymer particles containing sulfonate groups. The sorption capacity of the gel microspheres for doxorubicin was 2.2 mmol/g, significantly higher than the 0.4 mmol/g observed for the non-porous reference particles. The obtained values of doxorubicin sorption on gel microspheres are over 60 times higher than the values reported in the literature. Full article

Dielectric barrier discharge (DBD) plasma provides a solvent-free and energy-efficient approach for the in situ polymerization of styrene on cotton textiles. Traditional methods for polystyrene (PS) coating often require elevated temperatures, chemical initiators, or organic solvents, conditions that are incompatible with porous, heat-sensitive substrates such as cotton. In this work, we demonstrate that DBD plasma can initiate and sustain styrene polymerization directly on cotton fibers under ambient conditions. FT-IR spectroscopy confirms the consumption of the vinyl C=C bond and the formation of atactic, amorphous polystyrene. Thermogravimetric analysis indicates that the cotton coated with DBD polymerized PS exhibits enhanced thermal stability compared to cotton coated with commercial PS. Additionally, UV aging tests confirm that the plasma-deposited coating maintains its hydrophobicity after exposure to light. Together, these findings highlight DBD plasma as a sustainable and effective approach for producing hydrophobic, thermally robust, and UV-stable textile coatings without the need for solvents, initiators, or harsh processing conditions. Full article

This study compares the chemical modification and polymerization behavior of canola, carinata, and crambe oils to evaluate their suitability as renewable building blocks for polymer synthesis. The vegetable oils were characterized in terms of fatty-acid composition and oxidative stability, and the data showed distinct profiles: canola with 0% erucic acid, carinata around 42.08%, and crambe reaching 56.25%, differences that end up influencing how each one responds during the modification steps. Epoxidation and acrylation were confirmed by ¹H NMR, ¹³C NMR, and FTIR-ATR, mainly through the disappearance of the olefinic peaks and the appearance of oxirane- and acrylate-related signals (some of them quite clear, others less pronounced). After acrylation, the oils were subjected to solution polymerization, forming bulk crosslinked materials, whose properties reflected their original fatty-acid profiles: the canola-based polymer reached the highest glass transition temperature (T_g), 47.73 °C, followed by the carinata-based polymer (T_g = 41.86 °C), while the crambe-derived polymer, with lower functionality due to its high erucic acid content, showed a much lower T_g of 20.26 °C. Altogether, these differences highlight how variations in fatty-acid composition subtly shape the efficiency of functionalization and the architecture of the resulting networks. The polymers obtained here point to potential uses in renewable coatings, thermoset resins, and other applications that depend on bio-based crosslinked materials. Full article

This study reports the solvent-free synthesis, structural characterization, and performance evaluation of poly (methyl methacrylate-co-acrylic acid) [P(MMA-AA)] copolymers intended for use as sustainable concrete primers and industrial coatings. A series of copolymers with varying MMA-AA molar ratios were synthesized via bulk radical polymerization and characterized using ¹H and ¹³C nuclear magnetic resonance (NMR) spectroscopy, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The resulting materials were evaluated for their physical mechanical properties, including viscosity, tensile strength, surface hardness, and wettability. The findings revealed that higher MMA content improved the thermal stability, tensile strength, and hardness of the coatings, whereas increasing the AA content enhanced crosslinking density, hydrophilicity, and chemical resistance. These results demonstrate the potential of solvent-free P(MMA-AA) copolymers as environmentally friendly, high-performance alternatives to conventional solvent-based systems in protective coating applications. Full article

Sexually transmitted infections, notably herpes simplex virus, remain significant global health concerns. Localized delivery systems that provide sustained antiviral activity at mucosal surfaces offer an attractive alternative to systemic therapies. In this study, we developed electrohydrodynamically deposited coatings utilizing a covalent acyclovir–poly (lactic-co-glycolic acid) (ACV–PLGA) conjugate for potential antiviral functionalization of medical devices. The ACV–PLGA prodrug was synthesized via drug-initiated ring-opening polymerization, yielding a copolymer characterized by FTIR, NMR, GPC, and DSC, with controlled drug loading and biodegradable properties. Systematic optimization of electrospinning and electrospraying parameters enabled the fabrication of both particulate and nanofibrous coatings on silicone ring models. Morphological analysis by SEM demonstrated that polymer concentration, solvent composition, and applied voltage critically governed coating architecture, ranging from microparticle layers to uniform bead-free fibers. In vitro studies revealed morphology-dependent degradation profiles and sustained release of ACV over 56 days. This integrated approach combining covalent prodrug synthesis with tunable electrohydrodynamic deposition offers a promising strategy for long-acting local antiviral prophylaxis via functionalized medical surfaces. Full article

Traditional lithography processes use resist materials that require organic solvents during the development step but also often contain components derived from PFASs (per- and polyfluoroalkyl substances), raising concerns about environmental pollution and sustainability. PFASs are difficult to degrade, and their long-term effects on ecosystems and human health are the subject of international concern, making the development of alternative technologies an urgent priority. Lithography is a fundamental technology with applications beyond semiconductor manufacturing, electronics, biomedicine, and microfluidic devices. Addressing its environmental impact remains critical in both academic and industrial contexts. This study introduces a water-developable positive photoresist derived from a polymeric material incorporating plant-derived sugar chains as the resist backbone. The reactivity of the material to ultraviolet irradiation, enabled by a photoacid generator, allows microfabrication through water development. Moreover, successful micrometer-scale patterning demonstrated a superior resolution compared to previous sugar-derived water-developable resists. The dextrin-based resist exhibited the highest performance, achieving a sensitivity of 150 mJ/cm² and a resolution of 3.6 µm under an environmentally benign, PFAS-free process that enabled development with water. These findings propose a sustainable alternative to conventional petrochemical-derived photoresists, positioning it as a promising candidate for environmentally friendly photolithography processes. Full article

A chemical platform for post-polymerization methods was developed, starting from the ecodesign and enzymatic synthesis of safe and sustainable bio-based polyesters containing discrete units of itaconic acid. This unsaturated bio-based monomer enables the covalent linkage of molecules that can impart desired properties such as hydrophilicity, flexibility, permeability, or affinity for biological targets. Molecular descriptor-based computational methods, which are generally used for modeling the pharmacokinetic properties of drugs (ADME), were employed to predict in silico the hydrophobicity (LogP), permeability, and flexibility of virtual terpolymers composed of different polyols (1,4-butanediol, glycerol, 1,3-propanediol, and 1,2-ethanediol) with adipic acid and itaconic acid. Itaconic acid, with its reactive vinyl group, acts as a chemical platform for various post-polymerization functionalizations. Poly(glycerol adipate itaconate) was selected because of its higher hydrophilicity and synthetized via solvent-free enzymatic polycondensation at 50 °C to prevent the isomerization or crosslinking of itaconic acid. The ecotoxicity and marine biodegradability of the resulting oligoester were assessed experimentally in order to verify its compliance with safety and sustainability criteria. Finally, the viability of the covalent linkage of biomolecules via Michael addition to the vinyl pendant of the oligoesters was verified using four molecules bearing thiol and amine nucleophilic groups: N-acetylcysteine, N-Ac-Phe-ε-Lys-OtBu, Lys-Lys-Lys, and glucosamine. Full article

Mechanochemical methods have received much attention in the synthesis and design of all-solid-state battery materials in recent years due to their advantages of being green, efficient, easy to operate, and solvent-free. In this review, common mechanochemical methods, including high-energy ball milling, twin-screw extrusion (TSE), and resonant acoustic mixing (RAM), are introduced with the aim of providing a fundamental understanding of the subsequent material design. Subsequently, the discussion focuses on the application of mechanochemical methods in the construction of solid-state electrolytes, anode materials, and cathode materials, especially the research progress of mechanical energy-induced polymerization strategies in building flexible composite electrolytes and enhancing interfacial stability. Through the analysis of representative work, it is demonstrated that mechanochemical methods are gradually evolving from traditional physical processing tools to functional synthesis platforms with chemical reaction capabilities. This review systematically organizes its development and research trends in the field of all-solid-state battery materials and explores potential future breakthrough directions. Full article

In this study, alkali-treated wood flour/dynamic polyurethane composites were successfully prepared through a solvent-free one-pot method and in situ polymerization. The effects of the alkaline treatment process, changes in the flexible long-chain content in the dynamic polyurethane system, and the wood flour filling amount on the interface’s bonding, mechanical, and reprocessing properties were investigated. Partial removal of lignin and hemicellulose from the alkali-treated wood flour enhanced rigidity and improved interface bonding and mechanical strength when combined with dynamic polyurethane. The tensile strength was improved from 5.65–11.00 MPa to 13.08–23.53 MPa. As the composite matrix, dynamic polyurethane could not easily infiltrate all wood flour particles when its content was low or its fluidity was poor. Conversely, excessive content or overly high fluidity led to leakage and the formation of large pores, affecting the mechanical strength. As the polyol content increased, the matrix exhibited greater fluidity, which enabled it to accommodate more wood flour and penetrate the cell cavity or even the cell wall. This improved infiltration enhanced the interface bonding performance of the composites and made their mechanical properties sensitive to changes in wood flour content. The reprocessing ability of the prepared composites decreased with the increase in wood flour content, and the interface bonding was enhanced after reprocessing. The tensile strength retention rate of the composites prepared with alkali-treated wood flour was lower. This study provides a theoretical basis for optimizing the performance of wood fiber/dynamic polyurethane composites and an exploration path for developing self-healing and recyclable wood–plastic composites, which can be applied to building materials, automotive interiors, furniture manufacturing, and other fields. Full article

A series of Zn complexes containing guanidine– and amidine–phenolate ligands were synthesized and evaluated as catalysts for the polymerization of rac-lactide at 130 °C, under solvent-free conditions, giving rate constants in the range of 0.71–4.37 × 10^–4 s^–1. Polymerization under identical conditions with the guanidine– and amidine–phenol proligands themselves used as catalysts gave values in the range of 0.30–2.45 × 10^–4 s^–1. The stereoselective production of polylactic acid from either the Zn complexes or the proligands was limited (P_r = 0.47–0.62). The molecular weight of the polymers was lower than expected for living polymerizations due to chain transfer and/or transesterification but were comparable to those obtained in control experiments with Sn(Oct)₂. Full article

Hydrofluorocarbons (HFC) are today widely used as refrigerants, solvents, or aerosols for fire protection. Due to their non-negligible environmental impact, there exists an increasing interest towards their effective separation and recovery, which still remains a major challenge. This work presents a comprehensive thermodynamic and transport modeling approach able to describe HFC sorption and transport in different amorphous polymers, including glassy, rubbery, and copolymers, as well as in supported Ionic Liquid membranes (SILMs). In particular, the literature solubility data for refrigerants such as R-32, R-125, R-134a, and R-152a is analyzed by means of the Sanchez–Lacombe Equation of State (SL-EoS), and its non-equilibrium extension (NELF), to predict gas uptake in complex polymeric materials. The Standard Transport Model (STM) is then employed to describe permeability behaviors, incorporating concentration-dependent diffusion using a mobility coefficient and thermodynamic factor. Results demonstrate that fluorinated gases exhibit strong affinity to fluorinated and high free-volume polymers, and that solubility is primarily governed by gas condensability, molecular size, and polymer structure. The combined EoS–STM approach accurately predicts both solubility and permeability across different pressures in all polymers, including SILM. The thorough study of HFC transport in polymer membranes provided both systematic insights and predictive capabilities to guide the design of next-generation materials for refrigerant recovery and low-GWP separation processes. Full article

Poly(acrylic acid) (PAA) and hydroxypropylcellulose (HPC) hydrogels were synthesized in the absence of a crosslinker. Chemical crosslinking between PAA and HPC was demonstrated through free radical polymerization by a precipitation reaction in acetone as the solvent. These hydrogels exhibited smaller swelling ratios (1 to 5 g H₂O/g) than homo PAA hydrogels synthesized in water as the solvent. They were swollen in a 0.1 M NaOH solution and subsequently used to remove Ni²⁺ ions from aqueous solutions with concentrations ranging from 1000 to 4000 ppm. The absorption capacity of these hydrogels ranged from 91 to 340 mg of Ni²⁺/g in a rapid 1 h process, and from 122 to 435 mg of Ni²⁺/g in a 24 h process, demonstrating an improvement in Ni²⁺ absorption compared to previously reported hydrogels. The colored 1000 and 2000 ppm Ni²⁺ solutions became clear after treatment, while the PAA-HPC hydrogels turned green due to the uptake of Ni²⁺ ions, which were partially chelated by carboxylate groups as nickel polyacrylate and partially precipitated as Ni(OH)₂, resulting in an average absorption efficiency of 80%. The hydrogel was able to release the absorbed Ni²⁺ upon immersion in an HCl solution, with an average release percentage of 76.4%, indicating its potential for reuse. These findings support the use of PAA-HPC hydrogels for cleaning Ni²⁺-polluted water. The cost of producing 1 g of these hydrogels in laboratory conditions is approximately 0.2 USD. Full article