Poly(2-methoxyethyl acrylate) (PMEA) shows excellent blood compatibility because of the existence of intermediate water. Various modifications of PMEA by changing its main or side chain's chemical structure allowed tuning of the water content and the blood compatibility of numerous novel polymers. Here, we exploit a possibility of manipulating the surface hydration structure of PMEA by incorporation of small amounts of hydrophobic fluorine groups in MEA polymers using atom-transfer radical polymerization and the (macro) initiator concept. Two kinds of fluorinated MEA polymers with similar molecular weights and the same 5.5 mol % of fluorine content were synthesized using the bromoester of 2,

Development of high-performance electret materials is required to obtain a large power output of the electrostatic vibration-driven energy harvesters. In this study, by introducing aminosilane derivatives into CYTOP-based perfluorinated polymer film, we have successfully formed nano-clusters containing the organic siloxanes in the polymer electrets. Using small-angle x-ray scattering, tapping mode AFM and SEM analysis, the existence of such nano-clusters has been directly observed in the CYTOP film. It is suggested that the observed nano-clusters serve as the charge trap site and enhance the surface charge density and the thermal stability of the trapped charges. As a polymer electret, an extremely high surface charge potential of −1.6 kV with the 15 µm thick film has been obtained under the optimum condition of corona charging.

Atomistic computer simulations can provide insights into silicate glass‐environment interactions with the recent development of reactive potentials. However, the accuracy of generated glass structures with these potential was usually not fully examined. In this paper, the capability of the reactive force field (ReaxFF) to describe the short and medium range structure features of sodium silicate glasses in molecular dynamics simulations is investigated by comparing a widely used partial charge pairwise potential and available experimental data. Glass structure information such as pair distribution function (PDF), coordination number, Qn species, neutron broadened structure factor, and X‐ray broadened structure factor of the glass structures from ReaxFF simulations were calculated and compared to evaluate the generated glass structure. Advantages and limitations of the potentials and glass forming procedures, as well as areas of further improvement, were discussed. The results show that the recently refined ReaxFF parameters through the proposed procedure enable the simulations of sodium silicate glass structures with minimal defects, which paves the way to investigate water‐glass interaction mechanisms with the reactive enabled potentials.

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Air/fluoroalkyl acrylate polymer interfaces have been investigated by heterodyne-detected vibrational sum frequency generation (HD-VSFG) spectroscopy. As fluoroalkyl acrylate polymers, poly­(2-perfluorohexylethlyl acrylate) (p-C6FA) with the C6F13 group in its side chain and poly­(2-perfluorooctylethlyl acrylate) (p-C8FA) with the C8F17 group were examined. Although the two polymers differ only in the length of the fluoroalkyl group in their side chains, air/polymer interfaces of them gave quite different VSFG spectra. In the spectral range from 1300 to 1550 cm–1, the VSFG spectrum of the air/p-C8FA interface was dominated by a vibrational band at 1370 cm–1, whereas that of the air/p-C6FA did not show any discernible vibrational band. By reference to polarized HD-VSFG spectra of an air/fluorosurfactant interface combined with Raman measurements and quantum chemical calculations of the surfactant, the 1370 cm–1 VSFG band was ascribed to the terminal C–C stretch of the fluoroalkyl group coupled with the terminal CF3 symmetric stretch. Based on the assignment, we deduced that the orientation of the perfluoroalkyl side chains of p-C8FA is almost perpendicular to the interface. In contrast, we concluded that the perfluoroalkyl side chains of p-C6FA orient randomly with gauche defects or orient parallel to the interface. This difference in molecular structures and conformations may give rise to the differences in macroscopic properties at the interfaces. This study demonstrates that the 1370 cm–1 band observed in HD-VSFG spectroscopy can be used as a marker for the orientation and conformation of the CF3 groups in fluorinated compounds.