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A recent comment by Boivin et al. urges academia and governments to address sexism and fight bias at higher education and research institutions as losing female academics is costing science and society too much. Herein, I discuss further underlying reasons of sexism in academia and the importance of a deep dive into the causes of inequity at individual faculty and school levels to develop bespoke and enforceable gender equity plans, the importance of not using basic statistic as the only tool to measure equity/inequity as well as how key performance indicators could be better used to advance gender equity and end sexism in academia. [ABSTRACT FROM AUTHOR]

Green chemistry, sustainable chemistry, and circular chemistry are important concepts for the modern lifestyle, current research directions, and worldwide industries. These three concepts are closely related and interconnected but cannot be used synonymously. In addition, they are addressing two different economic models, i.e., linear economy and circular economy. The current contribution focuses on the importance of these decisive chemistries for the development of a sustainable future and their role in the realm of circular economy and the planetary boundaries framework—especially for the planetary boundary of "novel entities." Researchers active in the field of polymer chemistry play an important role as plastic pollution and resource in addition to environmental depletion, caused by the still increasing production of polymers and plastics, become more and more pronounced. It is also reported that multi‐ and interdisciplinary approaches are needed to develop solutions for a sustainable future. [ABSTRACT FROM AUTHOR]

This article categorizes and evaluates how regulatory regimes conceptualize plastics, and how such conceptualizations affect the production, consumption, and disposal of plastics. Taking a doctrinal and policy-oriented approach, it identifies four 'frames' – that is, four distinct and coherent sets of meanings attributed to plastics within transnational regulation – namely, plastics as waste to be managed; a material to be prevented; a good (or waste) to be traded freely; and inputs or outputs in production-consumption systems. Based on this analysis, three significant deficiencies in the transnational regulation of plastics are identified: the failure to frame plastics in terms of environmental justice and human rights issues; insufficient focus on plastics prevention (rather than management); and the role of law in reinforcing its production and consumption. [ABSTRACT FROM AUTHOR]

The plastic economy, despite offering unique properties in fulfilling the functions of products in different industrial sectors over decades, has so far been mainly linear, that is, "take‐make and dispose" with only a small fraction of plastics being recycled worldwide. With ever‐increasing circular economy initiatives and the urge to conserve resources and prevent plastic pollution from affecting ecosystems, more emphasis on the resource recovery of plastic products after its use has been made over the last few years. It is necessary for manufacturers to understand the value chain as early as the design phase while manufacturing and distributing plastic products across the world. The current study provides an overview of the status quo of plastic waste management and analyzes the Life Cycle Assessment (LCA) studies of different End‐of‐Life (EoL) options for plastics. Based on the LCA studies, a preliminary, country‐specific Circular Footprint (CF) is calculated and Design for Recycling (DfR) strategies are identified. Results show that the environmental impacts of different EoL options differ significantly for different plastics. The CF highlights the lack of data regarding the composition and recovery of plastics in different countries thus showing the necessity to consider the whole lifecycle when quantifying the environmental impacts of plastics. [ABSTRACT FROM AUTHOR]

The world's first-ever human-made synthetic polymer, "Parkesine", as it was called, was introduced in 1862 by Alexander Parkes at the London International Exhibition. An aromatic polyether network of lignin inspired Frederik Diness and colleagues (2100484) to design and synthesize high-temperature polymers similar to poly(bisphenol A sulfone) or polyether sulfone from lignin-derived small molecule, i.e. 4-hydroxybenzyl alcohol (4-HBA), via S SB N sb Ar reaction. [Extracted from the article]

Polyserotonin-based nanoparticles are a new class of bioinspired nanomaterial with recently demonstrated therapeutic potential for future clinical applications. It is therefore important to establish a robust and rapid method of synthesizing polyserotonin nanoparticles (PSeNP) in the size range ideal for in vivo utilization. Since the formation of PSeNP is base-catalyzed, here we report the influence of solution pH, in the presence of different base systems, on the kinetics of PSeNP formation and physico-chemical properties of the resulting nanoparticles. We show that the rate of formation and the size of PSeNP depend on both the nature of the base and the initial pH of the reaction. We have also improved the kinetics of particle formation by performing the synthesis at an elevated temperature (60 °C), leading to a dramatic reduction in synthesis time from days to hours. This presents a significant advance in the efficiency of PSeNP synthesis and provides a facile approach in tuning the size of nanoparticles to suit various applications. Furthermore, we show that similar to serotonin, PSeNP also exhibits free radical scavenging property. Our results demonstrate that PSeNP has the potential to become a key player in the advancement of nanotechnology-mediated antioxidative therapy. [ABSTRACT FROM AUTHOR]

A series of poly(sodium methacrylate) hydrogels, also called superabsorbents, having a theoretical degree of neutralization of 100 mol%, and degree of crosslinking varying from 0.6 to 20 mol%, are synthesized via conventional free radical polymerization. The networks are characterized in detail by inverse size‐exclusion chromatography and 1H‐NMR relaxometry in order to place particular emphasis on the investigation of the pore size distribution (PSD) and the chain mobility, respectively. The two previously mentioned parameters are compared to understand the correlation between the elastic chain mobilities and the average pore size of the hydrogel. From the resulting data, a new empirical equation is proposed, which is valid under the given experimental conditions and permits a rough estimation of the average PSD from the relaxation data. Thus, the equation permits to reduce the number of analytical techniques needed for the characterization of complex systems such as polymer networks. [ABSTRACT FROM AUTHOR]

We exploit the fluoride that is released via the para-fluoro-thiol reaction (PFTR) to cleave silyl ethers, turning the PFTR into an effective self-reporting chemiluminescence (CL) probe. The cleavage induces chemiluminescence and hence provides an optical read-out for the conversion of the PFTR. The PFTR chemiluminescence read-out is established on small molecule thiols, and subsequently expanded to polymers and networks. [ABSTRACT FROM AUTHOR]

Polymers and plastics play a very important part in the modern world and contribute to people's wellbeing and comfort. However, products made of them are contributing to land‐ and marine‐based environmental pollution due to littering and other ways of emission, and therefore threaten ecosystems worldwide. However, waste management and responses by governments and the consumer differ strongly from country to country. The current article provides an overview of several important aspects of polymer waste and plastic pollution as well as describes selected strategies to mitigate these using examples from Germany and Australia, and therefore aims to contribute to the resolution of the ever‐increasing problem of unsustainable plastic consumption, disposal, and pollution. [ABSTRACT FROM AUTHOR]

A new strategy for particle synthesis is enabled by utilizing modern synthetic, polymer, and photochemical techniques to facilitate the synthesis of highly narrow–disperse multifunctional microspheres from visible‐light induced crosslinking of prepolymers in both a single and dual polymer system. The approach requires no stabilizers, bases, or initiators, and proceeds at ambient temperature to yield microspheres with a tunable size range (0.25–5 µm) in less than 4 h, depending largely on solvent composition, but also polymer concentration (2–10 mg mL−1), ratio, and irradiation intensity (3–20 W). Critically, the visible‐light induced dimerization reaction exploited herein enables simple functional particle syntheses via a single polymer system. Underpinned by an in‐depth kinetic analysis of the particle formation as well as a detailed small molecule study, the mechanism for particle formation is also elucidated. Importantly, inherent advantages of the system are exploited for surface functionalization of residual acrylate and hydroxyl groups (generating inherently fluorescent particles). [ABSTRACT FROM AUTHOR]

Herein, we introduce a fast, additive-free, ambient temperature photochemical approach – utilising the novel Diels–Alder cycloaddition of a photo-active ortho-methylbenzaldehyde (oMBA) with a terminal alkyne – for preparing functional acid-sensitive profluorescent nano-/microspheres in one step. Not previously reported, the possibility of applying such a reaction in the context of particle synthesis provides new possibilities for particle design, where multi-step reactivity can be gated into distinct steps. First, a photochemically-gated particle formation step yields a material possessing a reactive, spring-loaded intermediate at every cross-linking point. A second, on-demand step to initiate fluorescence generation subsequently imparts the properties of the chemical transformation to the material itself. The synthesised particles are narrow-disperse with an average diameter ranging from 170–380 nm. [ABSTRACT FROM AUTHOR]

The peroxyoxalate chemiluminescence (PO‐CL) reaction is among the most powerful and versatile techniques for the detection of hydrogen peroxide (H2O2) and has been employed in various biological and chemical applications over the past 50 years. However, its two‐component nature (peroxyoxalate and fluorophore) limits its use. This contribution introduces an innovative and versatile photochemical platform technology for the synthesis of inherently fluorescent PO probes by exploiting the nitrile imine‐mediated tetrazole‐ene cycloaddition (NITEC) reaction. In the presence of hydrogen peroxide, the pioneered "2‐in‐1" molecule emits either yellow or blue light, depending on tetrazole (Tz) structure. Even in the absence of base, the emitted light remains visible and H2O2 could be detected in the nanomolar range. Critically, the PO‐Tz can be readily incorporated into polymeric materials. As a first application of this promising material, a tailor‐made PO‐Tz is grafted on poly(divinylbenzene) (PDVB) particles to enable solid‐phase chemiluminescence on microspheres. [ABSTRACT FROM AUTHOR]

We introduce a protecting‐group‐free concept for the powerful para‐fluoro‐thiol reaction (PFTR) employing a source of fluoride ions as base. The reaction is shown to be self‐propagating, with under‐stoichiometric amounts of base, thus effectively foregoing the need for high base concentrations. Careful tuning of the solvent–thiol combination allows for quantitative conversion, in some cases within a short timeframe, when only minimal amounts of base are used, allowing the PFTR reaction to essentially proceed base‐free. [ABSTRACT FROM AUTHOR]

A substrate‐independent and versatile coating platform for (spatially resolved) surface functionalization, based on nitroxide radical coupling (NRC) reactions and the formation of thermo‐labile alkoxyamine functional groups, was introduced. Nitroxide‐decorated poly(glycidyl methacrylate) (PGMA) microspheres, obtained through bioinspired copolymer surface deposition using dopamine and a nitroxide functional dopamine derivative as monomers, were conjugated with small functional groups in a rewritable process. Reversible coding of the nitroxide functional microspheres by NRC and decoding through thermal alkoxyamine fission were monitored and characterized by electron paramagnetic resonance (EPR) spectroscopy and X‐ray photoelectron spectroscopy (XPS). In addition, this nitroxide coating system was exploited in "grafting‐to" polymer surface ligations of poly(methyl methacrylate) (PMMA) and poly(2,2,2‐trifluoroethyl methacrylate) (PTFEMA) in spatially confined areas. Polymer strands terminated with an Irgacure 2959 (2‐hydroxy‐4′‐(2‐hydroxyethoxy)‐2‐methylpropiophenone) photoinitiator were obtained through chain‐transfer polymerization, and subsequently coupled to nitroxide‐immobilized poly(dopamine) (PDA)‐coated silicon substrates by using rapid photoclick NRC reactions. Light‐driven polymer surface coding was visualized by time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) and XPS imaging. Coating with nitroxide: A versatile, bioinspired nitroxide functional coating platform is presented for precise programming of various materials. Nitroxide‐coated polymeric microspheres with rewritable properties were manufactured, exemplified in consecutive nitroxide radical coupling (coding) and thermal alkoxyamine fission (decoding) reaction steps. Photoinduced dual‐polymer‐patterned surfaces were further generated highlighting the broad applicability of our nitroxide coating system. [ABSTRACT FROM AUTHOR]

Abstract: The synthesis of crosslinked polymeric microspheres (3.8–15.0 µm) via (2,2,6,6‐tetramethylpiperidin‐1‐yl)oxyl (TEMPO) initiated thiol‐ene dispersion polymerization under ambient conditions is reported for the first time. The initiating ability of TEMPO for the thiol‐ene reaction is validated by electron paramagnetic resonance (EPR) and 1H nuclear magnetic resonance (NMR) spectroscopy on model reactions between 1‐octadecanethiol and two electron deficient enes, n‐butylacrylate and divinyl sulfone. Critically, the TEMPO resonance observed in the EPR spectra decreases with time when TEMPO is mixed with thiol and an electron deficient ene. The 1H NMR spectra demonstrate formation of up to 90% of thioether under ambient conditions. Based on these model reactions, a variety of crosslinked polymeric microspheres are synthesized with excellent morphological stability using poly(vinyl pyrrolidone) as surfactant. The ability of the microspheres for a second TEMPO initiated thiol‐ene reaction is demonstrated by the ligation of fluorescein‐5‐maleimide (an ene) to the microspheres' surface containing excess of thiol functionality and by ligation of cysteine (containing a thiol group) to the microspheres' surface containing an excess of ene functionality. The synthesized polymeric microspheres are characterized using scanning electron microscopy, differential scanning calorimetry, Fourier‐transform infrared spectroscopy, zeta potential, and X‐ray photoelectron spectroscopy. [ABSTRACT FROM AUTHOR]

Abstract: We introduce a fluorescence‐based methodology enabling the quantification of ligation points in photochemically prepared polymer networks. Well‐defined α,ω‐tetrazole‐capped polymer strands prepared via RAFT polymerization are crosslinked under UV irradiation by a trimaleimide via nitrile imine mediated tetrazole–ene cycloaddition. Thus, for each linkage point a fluorescent pyrazoline ring is formed, resulting in fluorescent networks, which are degradable by aminolysis of the trithiocarbonate functionalities, leading to soluble fragments. The fluorescence emission of the soluble network fragments correlates directly with the number of pyrazoline moieties originally present in the network, thus providing a direct measure of the number of ligation points constituting the network. The herein introduced strategy based on a fluorescence readout is a powerful yet simple approach to quantify network formation processes applicable to a wide class of polymers accessible via RAFT. [ABSTRACT FROM AUTHOR]

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