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Fluorinated polymers are important materials that are widely used in many areas. Herein, we report the development of a metal-free photocontrolled radical polymerization of semifluorinated (meth)acrylates with a new visible-light-absorbing organocatalyst. This method enabled the production of a variety of semifluorinated polymers with narrow molar-weight distributions from semifluorinated trithiocarbonates or perfluoroalkyl iodides. The high performance of "ON/OFF" control and chain-extension experiments further demonstrate the utility and reliability of this method. Furthermore, to streamline the preparation of semifluorinated polymers, a scalable continuous-flow approach has been developed. Given the broad interest in fluorinated materials and photopolymerization, we expect that this method will facilitate the development of advanced materials with unique properties.

The reactions 12 Cϩ 116 Sn, 22 NeϩAg, 40 Arϩ 100 Mo, and 64 Znϩ 89 Y have been studied at 47A MeV projectile energy. For these reactions the most violent collisions lead to increasing amounts of fragment and light particle emission as the projectile mass increases. This is consistent with quantum molecular dynamics ͑QMD͒ model simulations of the collisions. Moving source fits to the light charged particle data have been used to gain a global view of the evolution of the particle emission. Comparisons of the multiplicities and spectra of light charged particles emitted in the reactions with the four different projectiles indicate a common emission mechanism for early emitted ejectiles even though the deposited excitation energies differ greatly. The spectra for such ejectiles can be characterized as emission in the nucleon-nucleon frame. Evidence that the 3 He yield is dominated by this type of emission and the role of the collision dynamics in determining the 3 H/ 3 He yield ratio are discussed. Self-consistent coalescence model analyses are applied to the light cluster yields, in an attempt to probe emitter source sizes and to follow the evolution of the temperatures and densities from the time of first particle emission to equilibration. These analyses exploit correlations between ejectile energy and emission time, suggested by the QMD calculations. In this analysis the degree of expansion of the emitting system is found to increase with increasing projectile mass. The double isotope yield ratio temperature drops as the system expands. Average densities as low as 0.36 0 are reached at a time near 100 fm/c after contact. Calorimetric methods were used to derive the mass and excitation energy of the excited nuclei which are present after preequilibrium emission. The derived masses range from 102 to 116 u and the derived excitation energies increase from 2.6 to 6.9 MeV/nucleon with increasing projectile mass. A caloric curve is derived for these expanded Aϳ110 nuclei. This caloric curve exhibits a plateau at temperatures near 7 MeV. The plateau extends from ϳ3.5 to 6.9 MeV/nucleon excitation energy.PACS number͑s͒: 25.70.Mn, 24.10.Lx

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Fluoropolymers have found broad applications for many decades. Considerable efforts have focused on expanding access toward main-chain fluorinated polymers. In contrast to previous polymerizations of gaseous fluoroethylenes conducted at elevated temperatures and with high-pressure metallic vessels, we here report the development of a photoorganocatalyzed reversible-deactivation radical alternating copolymerization of chlorotrifluoroethylene (CTFE) and vinyl ethers (VEs) at room temperature and ambient pressure by exposing to LED light irradiation. This method enables the synthesis of various fluorinated alternating copolymers with low Đ and high chain-end fidelity, allowing an iterative switch of the copolymerization between “ON” and “OFF” states, the preparation of fluorinated block alternating copolymers, as well as postsynthetic modifications.

Solid polymer electrolytes (SPEs) that can offer flexible processability, highly tunable chemical functionality, and cost effectiveness are regarded as attractive alternatives for liquid electrolytes (LE) to address their safety and energy density limitations. However, it remains a great challenge for SPEs to stabilize Li+ deposition at the electrolyte–electrode interface and impede lithium dendrite proliferation compared with LE‐based systems. Herein, a design of solid‐state fluorinated bifunctional SPE (FB‐SPE) that covalently tethers fluorinated chains with polyether‐based segments is proposed and synthesized via photo‐controlled radical polymerization (photo‐CRP). In contrast to the conventional non‐fluorinated polyether‐derived SPEs, FB‐SPE is able to provide conducting Li+ transport pathways up to ≈5.0 V, while simultaneously forming a LiF interaction that can enhance Li anode compatibility and prevent Li dendrites growth. As a result, the FB‐SPE exhibits outstanding cycling stability in Li||Li symmetrical cells of over 1500 operating hours at as high current density as 0.2 mA cm−2. A thin and uniform Li deposition layer and LiF‐rich SEI at the surface of Li anode are found, and stable cycling with average coulombic efficiencies of 99% is demonstrated in Li||LFP and Li||NCM all‐solid‐state batteries based on such bifunctional fluorinated SPEs. The interesting fluorine effect and effective self‐suppression of lithium dendrites will inform rational molecular design of novel electrolytes and practical development of all‐solid‐state Li metal batteries.