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Photocatalytic upcycling and depolymerization of vinyl polymers have emerged as promising strategies to combat plastic pollution and promote a circular economy. This mini review critically summarizes current developments in the upcycling and degradation of vinyl polymers including polystyrene and poly(meth)acrylates. Of these material classes, polymethacrylates possess the unique possibility to undergo a photocatalytic depolymerization back to monomer under thermodynamically favourable conditions, thus presenting significant advantages over traditional thermal strategies. Our perspective on current formidable challenges and potential future directions are also discussed. [ABSTRACT FROM AUTHOR]

ABSTRACT Block copolymer/nanoparticle (BCP/NP) composites have attracted much attention due to their easiness of fabricating nanoscopic hierarchical structures, and significantly enhanced chemical and physical properties of the nanocomposites. Most of the focus in co-assembly of BCPs and NPs has been placed on the controlled alignment of NPs, 'passively,' in the BCP domain. However, NPs with carefully designed interfacial properties 'actively' direct self-assembled structure of BCP in a nonconventional route. Herein, we review recent investigations of the self-assembly of BCP domains in thin films via the addition of structure-directing organic and inorganic NPs. Understanding the phase behavior of BCP/NP co-assembly along with the theoretical description can shed a light on the far-reaching potentials to creating nonconventional nanostructures rarely obtained via traditional fabrication tools. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016, 54, 118-127 [ABSTRACT FROM AUTHOR]

Block copolymer thin films are highly versatile and accessible materials capable of producing nanofeatures in the size regime of a few to hundreds of nanometers by a simple spin‐coating‐and‐anneal process. Unfortunately, this simple protocol usually leads to parallel microdomains, which limits the applicability of such nanofeatures. A great deal of effort has been put into achieving perpendicular microdomains, but those that incorporate thermal annealing are arguably the most practical and reproducible in the lab and industry. This review discusses the recent ongoing efforts on various thermal approaches to achieving perpendicular microdomains in order to provide the readers with a toolbox to work with. Thermally producing perpendicular block copolymer (BCP) microdomains in thin films is key to the further development of these materials in both academia and industry. In particular, doing so with non‐polystyrene‐block‐poly(methyl methacrylate) BCPs is important. This review discusses recent approaches to achieving this goal with various BCPs. [ABSTRACT FROM AUTHOR]

Retrieving the starting monomers from polymers synthesized by reversible deactivation radical polymerization has recently emerged as an efficient way to increase the recyclability of such materials and potentially enable their industrial implementation. To date, most methods have primarily focused on utilizing high temperatures (typically from 120 °C to 180 °C) to trigger an efficient depolymerization reaction. In this work, we show that, in the presence of Eosin Y under light irradiation, a much faster depolymerization of polymers made by reversible addition-fragmentation chain-transfer (RAFT) polymerization can be triggered even at a lower temperature ( i.e. 100 °C). For instance, green light, in conjunction with ppm amounts of Eosin Y, resulted in the accelerated depolymerization of poly(methyl methacrylate) from 16% (thermal depolymerization at 100 °C) to 37% within 1 hour, and finally 80% depolymerization after 8 hours, as confirmed by both 1 H-NMR and SEC analyses. The enhanced depolymerization rate was attributed to the activation of a macroCTA by Eosin Y, thus resulting in a faster macroradical generation. Notably, this method was found to be compatible with different wavelengths ( e.g. blue, red and white light irradiation), solvents, and RAFT agents, thus highlighting the potential of light to significantly improve current depolymerization approaches., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)