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Title: Dielectric performance of high permitivity nanocomposites: impact of polystyrene grafting on BaTiO 3 and TiO 2

Abstract

Polymer nanocomposites are a promising concept to improve energy storage density of capacitors, but realizing their hypothetical gains has proved challenging. The introduction of high permittivity fillers often leads to reduction in breakdown strength due to field exclusion, which intensifies the applied electric field within the polymer matrix near nanoparticle interfaces. This has prompted research in developing new nanoparticle functionalization chemistries and processing concepts to maximize particle separation. Herein, we compare the dielectric performance of blended nanocomposites to matrix free assemblies of hairy (polymer-grafted) nanoparticles (HNPs) that exhibit comparable overall morphology. The dielectric breakdown strength of polystyrene-grafted BaTiO3 (PS@BaTiO3) systems was over 40% greater than a blended nanocomposite with similar loading (~25% v/v BaTiO3). Hairy nanoparticles with TiO2 cores followed similar trends in breakdown strength as a function of inorganic loading up to 40% v/v. Dielectric loss for PS@BaTiO3 HNPs was 2-5 times lower than analogous blended films for a wide frequency spectrum (1 Hz to 100 kHz). For BaTiO3 content above 7% v/v, grafting the polymer chains to the nanoparticle significantly improved energy storage density and efficiency, likely due to the polymer canopy mitigating interfacial transport and restricting particle-particle hot-spots by establishing a finite minimum particle separation.

Authors:
 [1];  [1];  [1];  [1];  [1];  [2];  [2];  [1];  [1]
  1. Air Force Research Lab. (AFRL), Wright-Patterson AFB, OH (United States)
  2. Univ. of Southern California, Los Angeles, CA (United States)
Publication Date:
Research Org.:
Univ. of Southern California, Los Angeles, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1374189
Grant/Contract Number:
SC0006812
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nanocomposites
Additional Journal Information:
Journal Volume: 2; Journal Issue: 3; Journal ID: ISSN 2055-0324
Publisher:
Taylor & Francis
Country of Publication:
United States
Language:
English
Subject:
25 ENERGY STORAGE; 36 MATERIALS SCIENCE; 77 NANOSCIENCE AND NANOTECHNOLOGY; polymer nanocomposites; hairy nanoparticles; dielectric breakdown; barium titanate; titanium dioxide

Citation Formats

Grabowski, Christopher A., Fillery, Scott P., Koerner, Hilmar, Tchoul, Maxim, Drummy, Lawrence, Beier, Christopher W., Brutchey, Richard L., Durstock, Michael F., and Vaia, Richard A. Dielectric performance of high permitivity nanocomposites: impact of polystyrene grafting on BaTiO 3 and TiO 2. United States: N. p., 2016. Web. doi:10.1080/20550324.2016.1223913.
Grabowski, Christopher A., Fillery, Scott P., Koerner, Hilmar, Tchoul, Maxim, Drummy, Lawrence, Beier, Christopher W., Brutchey, Richard L., Durstock, Michael F., & Vaia, Richard A. Dielectric performance of high permitivity nanocomposites: impact of polystyrene grafting on BaTiO 3 and TiO 2. United States. doi:10.1080/20550324.2016.1223913.
Grabowski, Christopher A., Fillery, Scott P., Koerner, Hilmar, Tchoul, Maxim, Drummy, Lawrence, Beier, Christopher W., Brutchey, Richard L., Durstock, Michael F., and Vaia, Richard A. 2016. "Dielectric performance of high permitivity nanocomposites: impact of polystyrene grafting on BaTiO 3 and TiO 2". United States. doi:10.1080/20550324.2016.1223913. https://www.osti.gov/servlets/purl/1374189.
@article{osti_1374189,
title = {Dielectric performance of high permitivity nanocomposites: impact of polystyrene grafting on BaTiO 3 and TiO 2},
author = {Grabowski, Christopher A. and Fillery, Scott P. and Koerner, Hilmar and Tchoul, Maxim and Drummy, Lawrence and Beier, Christopher W. and Brutchey, Richard L. and Durstock, Michael F. and Vaia, Richard A.},
abstractNote = {Polymer nanocomposites are a promising concept to improve energy storage density of capacitors, but realizing their hypothetical gains has proved challenging. The introduction of high permittivity fillers often leads to reduction in breakdown strength due to field exclusion, which intensifies the applied electric field within the polymer matrix near nanoparticle interfaces. This has prompted research in developing new nanoparticle functionalization chemistries and processing concepts to maximize particle separation. Herein, we compare the dielectric performance of blended nanocomposites to matrix free assemblies of hairy (polymer-grafted) nanoparticles (HNPs) that exhibit comparable overall morphology. The dielectric breakdown strength of polystyrene-grafted BaTiO3 (PS@BaTiO3) systems was over 40% greater than a blended nanocomposite with similar loading (~25% v/v BaTiO3). Hairy nanoparticles with TiO2 cores followed similar trends in breakdown strength as a function of inorganic loading up to 40% v/v. Dielectric loss for PS@BaTiO3 HNPs was 2-5 times lower than analogous blended films for a wide frequency spectrum (1 Hz to 100 kHz). For BaTiO3 content above 7% v/v, grafting the polymer chains to the nanoparticle significantly improved energy storage density and efficiency, likely due to the polymer canopy mitigating interfacial transport and restricting particle-particle hot-spots by establishing a finite minimum particle separation.},
doi = {10.1080/20550324.2016.1223913},
journal = {Nanocomposites},
number = 3,
volume = 2,
place = {United States},
year = 2016,
month = 9
}

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  • Noble fluorescence nanocomposite compound based on barium titanate nanoparticles (BTO), polystyrene (PSt), and terbium ion (Tb{sup 3+}) was synthesized by a combination of surface-initiated reversible addition-fragmentation chain transfer (RAFT) polymerization, Friedel-Crafts alkylation reaction and coordinate chemistry. Initially, a modification of surface of BTO was conducted by an exchange process with S-benzyl S’-trimethoxysilylpropyltrithiocarbonate to create macro-initiator for polymerization of styrene. Subsequently, aryl carboxylic acid functionalized polystyrene grafted barium titanate (BTO-g-PSt-COOH) was generated by substitution reaction between 4-(Chloromethyl) benzoic acid and PSt chains. The coordination of the nanohybrids with Tb{sup 3+} ions afforded fluorescent Tb{sup 3+} tagged aryl carboxylic acid functionalized polystyrenemore » grafted barium titanate (BTO-g-PSt-Tb{sup 3+}) complexes. Structure, morphology, and fluorescence properties of nanohybrid complexes were investigated by respective physical and spectral studies. FT-IR and SEM analyses confirmed the formation of BTO-g-PSt-Tb{sup 3+}nanohybrids. Furthermore, TGA profiles demonstrated the grafting of aryl carboxylic acid functionalized polystyrene on BTO surface. Optical properties of BTO-g-PSt-Tb{sup 3+} complexes were investigated by fluorescence spectroscopy.« less
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