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A depolymerizable vitrimer that allows both reprocessability and monomer recovery by a simple and scalable one‐pot two‐step synthesis of vitrimers from cyclic lactones is reported. Biobasedδ‐valerolactone with alkyl substituents (δ‐lactone) has low ceiling temperature; thus, their ring‐opening‐polymerized aliphatic polyesters are capable of depolymerizing back to monomers. In this work, the amorphous poly(δ‐lactone) is solidified into an elastomer (i.e.,δ‐lactone vitrimer) by a vinyl ether cross‐linker with dynamic acetal linkages, giving the merits of reprocessing and healing. Thermolysis of the bulkδ‐lactone vitrimer at 200 °C can recover 85–90 wt% of the material, allowing reuse without losing value and achieving a successful closed‐loop life cycle. It further demonstrates that the new vitrimer has excellent properties, with the potential to serve as a biobased and sustainable replacement of conventional soft elastomers for various applications such as lenses, mold materials, soft robots, and microfluidic devices.

A new di‐tert‐butyl acrylate (diTBA) monomer for controlled radical polymerization is reported. This monomer complements the classical use oftert‐butyl acrylate (TBA) for synthesis of poly(acrylic acid) by increasing the density of carboxylic acids per repeat unit, while also increasing the flexibility of the carboxylic acid side‐chains. The monomer is well behaved under Cu(II)‐mediated photoinduced controlled radical polymerization and delivers polymers with excellent chain‐end fidelity at high monomer conversions. Importantly, this new diTBA monomer readily copolymerizes with TBA to further the potential for applications in areas such as dispersing agents and adsorbents. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem.2017,55, 801–807

The synthesis and systematic comparison of a comprehensive library of well‐defined polymer architectures based on poly(acrylic acid) is reported. Through the development of new synthetic methodologies, linear, single branched, precision‐branched comb, and star polymers were prepared and their performance as dispersants was evaluated. The ability to accurately control chain lengths and branch points allows the subtle interplay between structure and dispersant performance to be defined and affords critical insights into the design of improved polymeric additives for coating formulations. The general industrial relevance of ionic polymers and branched macromolecular architectures supports these design rules for a wide range of other applications and materials, including as additives for personal care products and in water treatment. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem.2019,57, 716–725