Palladium-catalyzed Suzuki−Miyaura cross-coupling was demonstrated to be a versatile reaction platform to install functional groups onto well-defined polymers derived from reversible addition−fragmentation chain-transfer (RAFT) polymerization. Cross-coupled products were achieved utilizing a range of functional boronic acids including, but not limited to, furan, alkyloxyphenyl, methacrylamide, trifluorophenyl, anthracene, and dimethylaminophenyl. High to quantitative degrees of functionalization were obtained by employing convenient reaction conditions at low to moderate temperatures (23−60 °C), within short reaction times (2−16 h), while using air-stable reagents at 1.5−3.0 equiv. of boronic acid. Specifically, a custom monomer, N-[2-(4-bromophenyl)ethyl]acrylamide (BPEA), was synthesized bearing a reactive handle for subsequent cross-coupling, and its chemical structure was verified using nuclear magnetic resonance. RAFT polymerization of BPEA revealed attributes of a successful reversible-deactivation radical polymerization (RDRP) yielding polymers with predetermined molecular weights and narrow dispersity values (Đ < 1.3). The retention of living chain ends was evidenced by efficient chain extension of poly(BPEA) with N-isopropylacrylamide producing a low dispersity diblock copolymer. Optimal functionalizations were found to be achieved through removal of the RAFT chain transfer agent and, in specific instances, by functionalizing statistical copolymers. The utility of this functionalization strategy, when combined with RDRP, has the ability to provide potentially thousands of structurally diverse functionalized polymers, elucidate quantitative structure−property relationships, and create new avenues to advanced polymeric architectures.

Nanoparticle synthesis was demonstrated via functionalization-induced self-assembly (FISA) of block copolymers using Suzuki–Miyaura cross-coupling. In situ self-assembly was triggered in organic media by the progressive installation of solvophobic pendant groups onto an initially soluble diblock copolymer, rendering the reactive block insoluble and causing the formation of spherical polymeric micelles. Self-assembly was found to depend on the percent functionalization (f %), where after a critical threshold micelles were accessible that increased in size with increasing f % values. We found the chemical nature of the installed functional group to be crucial for conducting FISA and for controlling the solution morphology, with relatively solvophilic adducts remaining as unimers and increasingly solvophobic adducts trending toward larger micelles, from ca. 40 to 100 nm in diameter. The core and corona of the anticipated micellar structure were visualized using fluorine mapping through electron energy loss spectroscopy, in conjunction with FISA achieved through pendent trifluorophenyl functionality. This work establishes FISA as a new, versatile synthetic strategy to create nanoparticles having tunable morphologies with potential application as molecular payload delivery vehicles.

Polymer micelles were formed using thiol-epoxide “click” chemistry to trigger functionalization-induced self-assembly (FISA) of block copolymers by modifying a reactive glycidyl methacrylate block with solvophobes.

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We report on the Falcon neuro event-based sensor (EBS) instrument that is designed to acquire data from lightning and sprite phenomena and is currently operating on the International Space Station. The instrument consists of two independent, identical EBS cameras pointing in two fixed directions, toward the nominal forward direction of flight and toward the nominal Nadir direction. The payload employs stock DAVIS 240C focal plane arrays along with custom-built control and readout electronics to remotely interface with the cameras. To predict the sensor's ability to effectively record sprites and lightning, we explore temporal response characteristics of the DAVIS 240C and use lab measurements along with reported limitations to model the expected response to a characteristic sprite illumination time-series. These simulations indicate that with appropriate camera settings the instrument will be capable of capturing these transient luminous events when they occur. Finally, we include initial results from the instrument, representing the first reported EBS recordings successfully collected aboard a space-based platform and demonstrating proof of concept that a neuromorphic camera is capable of operating in the space environment.