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Access to block copolymers from monomers that do not polymerize via a common mechanism requires initiation from a multifunctional species that allows orthogonal polymerization chemistries. We disclose a strategy to provide well‐defined polyacrylamido‐b‐polyether block copolymers by a one‐pot combination of photoiniferter polymerization and organocatalytic ring‐opening polymerization (ROP) using a hydroxy‐functionalized trithiocarbonate photoiniferter as the dual initiator at ambient temperature. Our results reveal good compatibility between the two polymerization systems and highlight that they can be performed in arbitrary order or simultaneously with good retention of the thiocarbonylthio functionality. We also demonstrate selective temporal control over the photoiniferter polymerization during concurrent ROP. We harnessed the efficiency of combining these polymerization systems to provide tailor‐made block copolymers from chemically distinct monomers.

A series of Diels–Alder (DA) crosslinked polymethacrylate networks covering a broad range of glass‐transition temperatures (T_g) was prepared to establish the relationship between theT_gand the thermal decrosslinking behavior of these networks. A series of permanently crosslinked and uncrosslinked analogues were also prepared to better understand the thermoset‐to‐thermoplastic transition occurring in the DA networks at elevated temperatures. The network series were studied using dynamic mechanical analysis, which established an inverse relationship betweenT_gand decrosslinking ability. Differential scanning calorimetry confirmed the viability of the DA linkages in all formulations, and a trapping experiment with 9‐anthracenemethanol demonstrated that even the least responsive network was capable of undergoing decrosslinking given appropriate thermal treatment. While polymer chain mobility has long been understood to be a critical factor in healable materials, this work verifies the importance of this parameter in the decrosslinking of DA networks. © 2019 Wiley Periodicals, Inc. J. Polym. Sci.2020,58, 193–203

Herein, we report the photoinitiated polymerization‐induced self‐assembly (photo‐PISA) of spherical micelles consisting of proapoptotic peptide–polymer amphiphiles. The one‐pot synthetic approach yielded micellar nanoparticles at high concentrations and at scale (150 mg mL⁻¹) with tunable peptide loadings up to 48 wt. %. The size of the micellar nanoparticles was tuned by varying the lengths of hydrophobic and hydrophilic building blocks. Critically, the peptide‐functionalized nanoparticles imbued the proapoptotic “KLA” peptides (amino acid sequence: KLAKLAKKLAKLAK) with two key properties otherwise not inherent to the sequence: 1) proteolytic resistance compared to the oligopeptide alone; 2) significantly enhanced cell uptake by multivalent display of KLA peptide brushes. The result was demonstrated improved apoptosis efficiency in HeLa cells. These results highlight the potential of photo‐PISA in the large‐scale synthesis of functional, proteolytically resistant peptide–polymer conjugates for intracellular delivery.