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The escalating demand for plastics has resulted in a surge of plastic waste worldwide, posing a monumental environmental challenge. To address this issue, a versatile photo‐oxidative degradation method applicable to seven distinct polymer families is proposed, comprising poly(isobutyl vinyl ether) (PIBVE), poly(2,3‐dihydrofuran) (PDHF), poly(vinyl acetate) (PVAc), poly(n‐butyl acrylate) (PBA), poly(methyl acrylate) (PMA), poly(vinyl chloride) (PVC), poly(dimethyl acrylamide) (PDMA), poly(ethylene oxide) (PEO), poly(oligo(ethylene glycol) methyl ether acrylate) (PEGMEA), and even poly(methyl methacrylate) (PMMA). This method employs photo‐mediated hydrogen atom transfer (HAT) followed by oxidation to promote polymer degradation. This reaction is carried out under aerobic condition in the presence of iron trichloride (FeCl3) as a photocatalyst in combination with low‐intensity purple light irradiation. The process can degrade up to 97% of the polymer in less than 3 h. This degradation process can be easily controlled by switching the light off, which allows for precise modulation of the degradation rate, enhancing the effectiveness of the method. Overall, this method provides a sustainable method for degrading various polymer types with low energy input. [ABSTRACT FROM AUTHOR]

Solvent‐free photopolymerization of vinyl monomers to produce high modulus materials with applications in 3D printing and photoswitchable materials is demonstrated. Polymerizable eutectic (PE) mixtures are prepared by simply heating and stirring various molar ratios of N‐isopropylacrylamide (NIPAM), acrylamide (AAm) and 2‐hydroxyethyl methacrylate (HEMA). The structural and thermal properties of the resulting mixtures are evaluated by 1D and 2D NMR spectroscopy as well as differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). UV photocuring kinetics of the PE mixtures is evaluated via in situ photo‐DSC and photorheology measurements. The PE mixtures cure rapidly and display storage moduli that are orders of magnitude greater than equivalent copolymers cured in an aqueous medium. The versatility of these PE systems is demonstrated through the addition of a photoswitchable spiropyran acrylate monomer, as well as applying the PE formulation as a stereolithography (SLA)‐based 3D printing resin. Due to the hydrogen‐bonding network in PE systems, 3D printing of the eutectic resin is possible in the absence of crosslinkers. The addition of a RAFT agent to reduce average polymer chain length enables 3D printing of materials which retain their shape and can be dissolved on demand in appropriate solvents. [ABSTRACT FROM AUTHOR]

The ability to revert polymers to their original monomers represents a crucial chemical recycling technique, promoting sustainability and offering the chance to convert used materials into valuable products. In recent years, numerous studies have explored the use of polymers synthesized via reversible deactivation radical polymerization (RDRP) techniques to facilitate efficient depolymerization reactions. Herein, we report the use of a photocatalyst, zinc tetraphenylporphyrin (ZnTPP), along with light irradiation to accelerate depolymerization of polymers prepared by reversible addition‐fragmentation chain transfer (RAFT) polymerization. We explore various parameters affecting depolymerization efficiency, including solvents, reaction temperature (80, 100, and 120°C), the presence of photocatalysts (ZnTPP and Eosin Y), and the type of RAFT end‐groups, namely trithiocarbonate, dithiobenzoate, and 1H‐pyrazole‐1‐carbodithioate. For instance, when PMMA was diluted to 25 mM in 1,4‐dioxane and heated to 120°C under green light irradiation in the presence of ZnTPP (200 ppm), rapid depolymerization exceeding 70% occurred within 1 h. Without ZnTPP, under similar conditions, the reaction required over 8 h to achieve a slightly lower yield. Furthermore, this method confers moderate oxygen tolerance to the system, enabling depolymerization to proceed without the need of deoxygenation, albeit at a lower rate and consequently lesser monomer recovery (31%). [ABSTRACT FROM AUTHOR]

More than two million people worldwide are affected by life-threatening, invasive fungal infections annually. Candida species are the most common cause of nosocomial, invasive fungal infections and are associated with mortality rates above 40%. Despite the increasing incidence of drug-resistance, the development of novel antifungal formulations has been limited. Here we investigate the antifungal mode of action and therapeutic potential of positively charged, synthetic peptide mimics to combat Candida albicans infections. Our data indicates that these synthetic polymers cause endoplasmic reticulum stress and affect protein glycosylation, a mode of action distinct from currently approved antifungal drugs. The most promising polymer composition damaged the mannan layer of the cell wall, with additional membrane-disrupting activity. The synergistic combination of the polymer with caspofungin prevented infection of human epithelial cells in vitro, improved fungal clearance by human macrophages, and significantly increased host survival in a Galleria mellonella model of systemic candidiasis. Additionally, prolonged exposure of C. albicans to the synergistic combination of polymer and caspofungin did not lead to the evolution of tolerant strains in vitro. Together, this work highlights the enormous potential of these synthetic peptide mimics to be used as novel antifungal formulations as well as adjunctive antifungal therapy. Fungal infections are severely underestimated as a cause of mortality, and alternative drugs are urgently needed. Here, Schaefer et al. show that a synthetic polymer mimicking defensins shows different, but synergistic activity with known antifungals. [ABSTRACT FROM AUTHOR]

Traditionally, combining carbon and ceramic materials has been challenging due to their different chemical and physical properties. Despite the development of numerous methodologies for their synthesis, these techniques frequently necessitate intricate, multi‐stage protocols and specialized equipment. This study introduces a novel approach for fabricating nanostructured carbon‐ceramic multimaterials through polymerization‐induced microphase separation 3D printing. By combining inorganic precursors, polycarbosilane, and acrylonitrile (AN) within a photocurable resin, heterogeneous nanostructured materials composed of PAN‐preceramic and sacrificial polymer phases are 3D printed. Upon pyrolysis, PAN‐preceramic domains transformed into a carbon‐ceramic matrix while sacrificial polymer domains thermally decomposed to yield nanoscale voids. The utilization of synchrotron X‐ray spectroscopy and microscopy techniques revealed that the phase compositions and microstructure of the resulting multi‐materials are significantly influenced by the initial composition of the resins. The co‐existence of ceramic and carbon phases within a single 3D printed material brought together a combination of properties from both phases, such as the low thermal conductivity of ceramics and the relatively high electrical conductivity of carbon, along with the exceptional chemical resistance. The insights into the microstructure, atomic configuration, and property relationships of the resulting materials have broad implications for the development of multi‐phase nanostructured hybrid materials. [ABSTRACT FROM AUTHOR]

Ion‐exchange materials are commonly composed of polyelectrolyte networks in which crosslinking preserves macroscopic geometry and prevents dissolution in aqueous conditions. However, crosslinking inherently inhibits efficient swelling and mass transfer during ion‐exchange processes. Herein, a one‐step polymerization‐induced microphase separation (PIMS) approach directly using water and linear polystyrene sulfonate macromolecular chain transfer agents (macroCTAs) is developed to engineer bicontinuous nanostructured materials with rapid ion‐exchange capabilities. These materials feature water‐swollen liquid‐like polyelectrolyte domain embedded in a rigid polymer network, where the domain spacing, as determined by small angle X‐ray scattering experiments, is precisely modulated between 15 and 89 nm based on the molecular weight of the macroCTA used. As the bicontinuous nanostructure enables rapid mass transfer throughout the material bulk, the 3D printed PIMS materials are able to rapidly remove model charged dyes from solution, exhibiting a mass transfer coefficient ≈35 times higher than commercially available counterparts. This work is the first example demonstrating direct self‐assembly of water into continuous nanochannels in a well‐controlled manner as supported by time‐resolved small‐angle neutron scattering experiments during polymerization. Moreover, these nanostructured materials are readily produced using commercially available 3D printers, enabling unparalleled high‐resolution fabrication of targeted complex structures, including accurately controllable macroporous geometries and surface areas. [ABSTRACT FROM AUTHOR]