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This review provides a detailed overview of the latest developments using nanoscale strategies in the field of polymeric and polymer nanocomposite materials for emerging dielectric capacitor-based energy storage applications. Among the various energy storage devices, solid-state dielectric capacitors possess the advantage of high-power density which makes them highly attractive for pulsed power applications. Polymers are particularly suitable for dielectric energy storage applications because of their high breakdown strength, low dielectric loss, formability, self-healing capability, flexibility, solvent processability, and graceful breakdown failure. Strategies to enhance the dielectric breakdown strength of polymeric dielectric capacitors are emphasized in this review. General background on breakdown mechanism, breakdown characteristics, and factors influencing polymer dielectrics breakdown are introduced. Given that polymers have low permittivity, strategies to substantially enhance dipole mobility and hence the permittivity, are highlighted. We discuss strategies to address permittivity contrast between nanofillers and the polymer matrix including the potential for developing gradient permittivity structured nanofillers. To improve the compatibility of nanofiller with polymer and minimize nanofiller aggregation, different routes to surface functionalize nanoparticles are presented. An outlook and future perspectives section are provided for the design of high energy density polymer film capacitors. [ABSTRACT FROM AUTHOR]

Block copolymers (BCPs) have received significant attention as promising candidates for sequestering nanoparticles and fabrication of aligned nanostructures with optimal optical or electrical properties. We investigate the influence of static and dynamic thermal field on the alignment of polystyrene‐block‐poly(methyl methacrylate) (PS‐b‐PMMA) BCP morphology with the loading of novel poly(methyl methacrylate‐block‐Polystyrene) (PMMA‐b‐PS)‐grafted‐TiO2 nanoparticles (BCP‐g‐TiO2). Observation of characteristics IR peaks for PMMA and PS in BCP‐g‐TiO2 nanoparticles and Transmission Electron Microscopy (TEM) results of the outer coating of core nanoparticle, validate the grafting to approach in synthesizing BCP‐g‐TiO2. Here we report that under the sharp dynamic thermal field, at low loading of BCP‐g‐TiO2, there is good dispersion of nanoparticles in unidirectionally aligned BCP matrix in film interior probed by GISAXS, while, at high nanoparticle loading (~10 wt%), there is local frustration in the unidirectional alignment of the BCP matrix due to aggregation of BCP‐g‐TiO2 nanoparticles. However, Grazing incidence small angle X‐ray scattering (GISAXS) shows clearly that the BCP films remain largely locally ordered at the domain scale, despite these large perturbations to long‐range ordering even at high loading level, while bringing in new TiO2 functionality to the BCP films, such as UVO absorptivity or biofouling prevention, important to potential new applications of such membranes. [ABSTRACT FROM AUTHOR]

ABSTRACT The objective of the study is to formulate exclusive block copolymer (BCP) nanocomposites by dispersing bcp end-grafted nanoparticles (bcp- g-nps) of PMMA- b-PS- g-TiO2 within PS- b-PMMA matrix. PMMA- b-PS- g-TiO2 is synthesized using a 'grafting-to' approach and characterized by XPS and TGA to establish that the copolymer chains were bonded to NPs. Good dispersion of bcp- g-nps in PMMA and PS-PMMA bcp films is observed, in contrast to poor dispersion in PS films. In PS-PMMA films, the compatible and identical bcp nature of the end-grafted polymer, and large NP size caused it to span across entire PS-PMMA domains. Poor and good dispersion in PS and PMMA matrices, respectively, can be rationalized by the fact that NPs interactions are driven by the PMMA at the outer corona of the bcp- g-nps. Developing bcp- g-nps as a strategic route to preparation of highly dispersed high permittivity NPs like titanium dioxide (TiO2) in bcp matrix can have important ramifications for energy storage devices. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 468-478 [ABSTRACT FROM AUTHOR]