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Dielectric polymer film capacitors having high energy density, low loss and fast discharge speed are highly desirable for compact and reliable electrical power systems. In this work, we study the confined ferroelectric properties in a series of poly(vinylidene fluoride‐co‐chlorotrifluoroethylene)‐graft‐polystyrene [P(VDF‐CTFE)‐g‐PS] graft copolymers, and their potential application as high energy density and low loss capacitor films. Thin films (ca. 20 μm) are prepared by different processing methods, namely, hot‐pressing or solution‐casting followed by mechanical stretching at elevated temperatures. After crystallization‐induced microphase separation, PS side chains are segregated to the periphery of PVDF crystals, forming a confining interfacial layer. Due to the low polarizability of this confining PS‐rich layer at the amorphous–crystalline interface, the compensation polarization is substantially decreased resulting in a novel confined ferroelectric behavior in these graft copolymers. Both dielectric and ferroelectric losses are significantly reduced at the expense of a moderate decrease in discharged energy density. Our study indicates that the best performance is achieved for a P(VDF‐CTFE)‐g‐PS graft copolymer with 34 wt‐% PS; a relatively high discharged energy density of approximately 10 J cm−3 at 600 MV m−1, a low dielectric loss (tanδ = 0.006 at 1 kHz), and a low hysteresis loop loss (17.6%) at 550 MV m−1.

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Six different anionic species (fluoride, chloride, bromide, iodide, nitrate, and acetate) are tested for their abilities to form anionic adducts with neutral oligosaccharides that are detectable by MALDI-TOF mass spectrometry. Fluoride and acetate cannot form anionic adducts with the oligosaccharides in significant yields. However, bromide, iodide, and nitrate anionic adducts consistently appear in higher abundances relative to [M Ϫ H] Ϫ , just like the highly stable chloride adducts. Post-source decay (PSD) decompositions of Br Ϫ , IϪ , and NO 3 Ϫ adducts of oligosaccharides provide no structural information, i.e., they yield the respective anions as the main product ions. However, determination of linkage types is achieved by analysis of structurally-informative diagnostic peaks offered by negative ion PSD spectra of chloride adducts of oligosaccharides, whereas the relative peak intensities of pairs of diagnostic fragment ions allow differentiation of anomeric configurations of glycosidic bonds. Thus, simultaneous identification of the linkage types and anomeric configurations of glycosidic bonds is achieved. Our data indicate that negative ion PSD fragmentation patterns of chloride adducts of oligosaccharides are mainly determined by the linkage types. Correlation may exist between the linkage positions and fragmentation mechanisms and/or steric requirements for both cross-ring and glycosidic bond fragmentations. PSD of the chloride adducts of saccharides containing a terminal Glc␣1-2Fru linkage also yields chlorine-containing fragment ions which appear to be specifically diagnostic for a fructose linked at the 2-position on the reducing end. This also allows differentiation from saccharides with a 1-1 linked pyranose on the same position. ollowing the advances in proteomics, there is a growing interest in the importance of glycomics, i.e., the study of the breadth of sugar forms (structure and function of glycans) in biological organisms. Carbohydrates (or saccharides) are the most abundant biological compounds found on earth. They are well known as energy reservoirs and structural materials in cell walls. However, it has become clear that oligosaccharides and glycoconjugates (e.g., glycoproteins and glycolipids) serve as crucial mediators for a wide variety of complex cellular events [1]. Carbohydrates also play an important role in specific molecular recognition, protein folding, stability, and pharmacokinetics due to their great structural diversity. Moreover, glycosylation is a ubiquitous form of post-translational modification to both proteins and lipids.Gaining a clear understanding of the crucial biological roles of oligosaccharides requires complete structural characterization of carbohydrates or glycoconjugates, which includes determinations of the numbers and types of monosaccharide units, ring substituents, sequences, branching, linkage positions, and anomeric configurations between adjacent monosaccharide units. In most cases, merely knowing the monosaccharide sequence is inadequate; thus, unam...