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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.

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.

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.

The Centre for a Waste-Free World supports the Productivity Commission’s examination of the ‘right to repair’ and the draft recommendations that have followed from its inquiry. We understand that this inquiry into the right to repair is being undertaken in conjunction with other actions by the Federal Government in support of the circular economy, including: the Treasury’s proposed scheme for the mandatory sharing of car repair information, the recent review of the Product Stewardship Act 2011(Cth), and the ACCC’s 2020 enquiry into agricultural machinery and the after-sales market (which includes examination of an agricultural right to repair). This inquiry also coincides with significant ongoing US policy developments on the ‘right to repair’ The Centre broadly supports the reform recommendations made by the Commission and believes that the adoption of these recommendations, via legislative changes and supporting frameworks, would positive contribute to slowing the consumption of resources/materials in line with the aim of a circular economy. We also support the Productivity Commission’s recognition of the fact that various factors currently restrict the ability and capacity of citizen- consumers to utilise ‘repair’ options. For example, corporate practices, design considerations, and lack of infrastructure and knowledge. The Productivity Commission subsequently acknowledges that enabling the right to repair is multi-faceted, requiring various regulatory, cultural and economic changes. We agree that progress towards a right to repair engages consumer and competition law, intellectual property, product design, labelling standards, and environmental and resource management. We also agree that Australia needs to implement appropriate legislative and policy responses that aim to generate, support and encourage the right to repair generally, and the right for consumers to access domestic repair services specifically. The implementation of such laws would bring

The Gold Coast City Marina & Shipyard (GCCM) embarked on an ambitious strategic action plan in 2021 to manage, recover and convert waste into valuable commodities. It represents a deeper endeavour to help the Marina and its associates steer towards a cleaner and healthier future. GCCM and the Australian Government commissioned the Centre for a Waste-Free World at Queensland University of Technology to provide leading research into transformative solutions to advance new economies for waste. A holistic program was designed to transition to sustainable resource use over one year for future extension. The scope of the project covers three phases, beginning with an evaluation of the existing waste products and processes for disposal and recycling to determine the new measures for landfill diversion and sustainable resource use that lend commercial opportunities.

Boat repair and maintenance effect surrounding coastal environments. Facility operators are often unaware of the environmental risks posed by their practices regarding wastes, particularly the harm caused by toxic paint chips, paint residues and other solid and liquid wastes containing heavy metals, acids, oil, hydrocarbons, and marine pest species. Key to this transformation is finding solutions to lower the impacts and turn waste into valuable resources through innovation and technology. Current challenges that have been identified on site at the Gold Coast City Marina & Shipyard include: lack of access to recycling options across the yard due to the large area and limitations of only having mainstream recycling options; lack of understanding by businesses about waste resources and how they can be recycled or repurposed in other ways; and lack of ability to translate the initial costs of investment into alternative waste management options for short-term savings in lower landfill fees and long-term savings in finding markets for reusable materials. GCCM has stepped up to join fellow industry leaders worldwide that are taking initiatives for responsible consumption and production. It facilitated an engagement workshop with its key target publics to determine optimal and concrete pathways to bring this agenda to fruition. This report was prepared on the research findings. It outlines a plan, spanning design, use, disposal, and collection of end-of-life materials for repurposing that is fundamental to drive linear thinking towards actualising meaningful circular practices over one, five, and twenty-five years.

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.

Visible light-triggered reversible triazolinedione (TAD) chemistry was already reported in the 1970s but it has only recently been introduced into the field of materials science, and as such remains relatively unexplored. Here, we exploit the reversible naphthalene-TAD Diels-Alder couple to crosslink pre-synthesized polymers in a precipitation-like polymerization to form narrow disperse microparticles. The approach does not require additives such as stabilizers or initiators and proceeds to deliver particles under relatively mild conditions in less than 1 h. While the crosslinked particles maintain their shape upon continuous irradiation with green light, the particles can be readily degraded in the dark at ambient temperature through a spontaneous cycloreversion process. In addition, the formation and degradation rate can be tuned by employing shorter or longer prepolymers, with particles synthesized from larger polymers degrading slower compared to their shorter polymer counterparts. The particle formation, light-stabilization and degradation were characterized in-depth by scanning electron microscopy (SEM) and online static light scattering experiments. In particular the particles' tuneable intrinsic degradation behaviour could hold key potential, for instance, in long term drug or fertilizer delivery systems.

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.

An average of 1.6 to 1.8 million mattresses are disposed of annually in Australia (Planet Ark Recycling, 2020). Only a small percentage are recycled. The majority of mattresses post-consumer use wind up in landfill. Each one amounts to .75m3 space (soft landing, n.d.), and the leeching of flammable chemicals may precipitate fires on site. Collectively, this practice has contributed to a waste crisis that requires better solutions. This report looks at mattress components, disposal practices post-consumer use, and waste recycling methods. Manual to technological recycling processes have been evaluated to show opportunities through research and development for improved health, safety, reduced environmental risks, and extended life cycle of resources.

The strength of combining experimental design and advanced kinetic Monte Carlo (kMC) modeling to understand step-growth network synthesis, commencing with a linear/star polymeric precursor, is illustrated considering three chemistries: (i) para-fluoro-thiol reaction (PFTR); (ii) nitrile imine-mediated tetrazole-ene cycloaddition (NITEC); and (iii) star poly(ethylene oxide-stat-propylene oxide) (sPEG)-amine-epoxy click reaction. Chemical parameters are determined based on small-molecule systems (monofunctional analogues) and diffusion parameters based on literature data and higher-network-yield data. Overall model validation is performed considering molar mass and spectroscopic experimental data. As basic support, kMC modeling provides the evolution of the complete size exclusion chromatography trace for both the soluble and the insoluble fraction at any time. In more detail, kMC modeling allows one to construct, whenever desired, two-dimensional traces such as the distribution of species with a given molar mass and number of cross-linking points (CPs) of a given type (e.g., with at least three cross-links), still differentiating between the soluble and insoluble fractions. Ultimately, postprocessing of kMC modeling results allows one to calculate distributions regarding distances between specific functional groups and the molecular pore size distribution upon considering a three-dimensional representation of the molecular buildup of individual network molecules. Also, the (relative) importance of reaction pathways can be assessed. It is, for instance, shown that diffusional limitations on intermolecular reactions determine how far a polymer network yield can be pushed, with a strong effect due to an intrinsically fast maleimide incorporation step, specifically for NITEC. Too long linear precursor building blocks should be avoided as they induce too prominent diffusional limitations. Too short linear precursor building blocks promote intramolecular reactions. With

The synthesis of single chain nanoparticles (SCNPs) is a vibrant field in macromolecular science, enabled by a rich variety of synthetic strategies to induce macromolecular chain folding. Due to the decrease of the hydrodynamic volume upon folding, SCNP formation is typically characterized by a shift towards higher elution volumes in size exclusion chromatography (SEC). However, a step-change in the methodologies for SCNP analysis is required for the in-depth understanding of the nature of intramolecular polymer folding and internal SCNP structure, which is critical to enable their application as catalytic nanoreactors. Herein, we exploit a unique combination of small-angle neutron scattering (SANS), 19F NMR spectroscopy, and quadruple detection SEC to generate an encompassing and systematic view of the folded morphology of poly(tert-butyl acrylate) based-SCNPs as a function of their reactive group density (5, 15, and 30 mol%) and absolute molar mass (20, 50, 100 kDa). In addition to detailed morphological insights, we establish that the primary factor dictating the compaction of SCNPs is their reactive group density, which is ineffective below 5 mol%, reaching maximum compaction close to 30 mol%. The molar mass of the precursor polymers has a minor impact on how an SCNP compacts for molar masses above 20 kDa. This journal is

The intramolecular chain collapse of linear precursors with systematic variation of molar mass and ligation group density (5, 15, and 30 mol %) into single-chain nanoparticles (SCNPs) was studied by two different separation approaches. The efficiency of size exclusion chromatography with quadruple detection (SEC-D4) was compared to asymmetrical field flow fractionation hyphenated to quintuple detection (AF4-D5) in organic solvent. The application of the unique combination of advanced detection to different separation principles opens up the opportunity to critically evaluate the determination of molar masses and different types of radii for an in-depth understanding of the structural properties affected by the internal folding process. This is achieved by a detailed comparison of assets, drawbacks, and limitations of these approaches based on the systematical screening of different chain lengths and sizes of the precursors and the SCNPs. Furthermore, an alternative strategy for quantitative determination of intramolecular ligation density by a combination of AF4 and UV detection is introduced.

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. This journal is

Herein, we introduce a comprehensive methodology to map the reactivity of photochemical systems on surfaces. The reactivity of photoreactive groups in solution often departs from their corresponding solution absorption spectra. On surfaces, the relationship between the surface absorption spectra and reactivity remains unexplored. Thus, herein, the reactivity of an o-methylbenzaldehyde and a tetrazole, as ligation partners for maleimide functionalized polymers, was investigated when the reactive moieties are tethered to a surface. The ligation reaction of tetrazole functionalized surfaces was found to proceed rapidly leading to high grafting densities, while o-methylbenzaldehyde functionalized substrates required longer irradiation times and resulted in lower surface coverage at the same wavelength (330 nm). Critically, wavelength resolved reactivity profiles were found to closely match the surface absorption spectra, contrary to previously reported red shifts in solution for the same chromophores.

The morphology of surfaces critically influences their interaction with the surrounding phase. Herein, we report a modular approach for the synthesis of organic-inorganic raspberry-, strawberry-, and seedpod-like particles to template the porosity of superficially porous particles. Divinylbenzene (DVB) microspheres were employed as core particles, which were modified with polar and nonpolar polymer shells. Subsequently, silica nanoparticle templates were covalently tethered to said particles. Further grafting of polymer shells and subsequent template removal yielded superficially porous core-shell particles. In addition, we introduce a facile procedure for the synthesis of superficially porous particles without distinguishable core-shell morphology. Organic seedpod-like particles were prepared from DVB and silica templates, yielding superficially porous particles after template removal. The surface morphology of the templated particles was investigated via scanning electron microscopy (SEM), transmission electron microscopy (TEM), and atomic force microscopy (AFM). X-ray photoelectron spectroscopy (XPS) was performed to prove the chemical modification of the particle surfaces.

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.

Herein, we introduce a fast, additive-free, ambient temperature photochemical approach - utilising the novel Diels-Alder cycloaddition of a photo-activeortho-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.

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).

An in-depth investigation of the network topology for a series of sodium acrylate hydrogels synthesized via conventional free radical polymerization (FRP) and reversible addition–fragmentation chain transfer (RAFT) polymerization is conducted. The role of the RAFT agent on the crosslinking process is demonstrated on a model system upon analysis of the reaction mixture via size-exclusion chromatography before the gelation point. For a comprehensive study, both the impact of the amount of RAFT agent and of the degree of crosslinking on the microstructure of the final product are systematically investigated. In addition to swelling experiments and oscillatory shear rheology measurements, the resulting networks are analyzed via low-field proton nuclear magnetic resonance (1H-NMR) techniques such as transverse relaxation and double-quantum coherence to evaluate the network mobility, which is then correlated to structural inhomogeneity. A broader mobility distribution is observed for the RAFT mediated networks compared to the FRP samples, which can be assigned to a higher content of dangling ends in the former case. The results are further elaborated to propose a mechanism for network formation in presence of a RAFT agent. Special Issue: 100 Years of Macromolecular Chemistry and Physics