skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Breakdown properties of epoxy nanodielectric

Abstract

Recent developments in polymeric dielectric nanocomposites have shown that these novel materials can improve design of high voltage (hv) components and systems. Some of the improvements can be listed as reduction in size (compact hv systems), better reliability, high energy density, voltage endurance, and multifunctionality. Nanodielectric systems demonstrated specific improvements that have been published in the literature by different groups working with electrical insulation materials. In this paper we focus on the influence of in-situ synthesized titanium dioxide (TiO{sub 2}) nanoparticles on the dielectric breakdown characteristics of an epoxy-based nanocomposite system. The in-situ synthesis of the particles creates small nanoparticles on the order of 10 nm with narrow size distribution and uniform particle dispersion in the matrix. The breakdown strength of the nanocomposite was studied as a function of TiO{sub 2} concentration at cryogenic temperatures. It was observed that between 2 and 6wt% yields high breakdown values for the nanodielectric.

Authors:
 [1];  [1];  [1];  [1];  [1];  [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
OE USDOE - Office of Electric Transmission and Distribution
OSTI Identifier:
991183
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Conference
Resource Relation:
Conference: IEEE Conference on Electrical Insulation and Dielectric Phenomenon, LaFayette, IN, USA, 20101018, 20101018
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; BREAKDOWN; CRYOGENICS; DESIGN; DIELECTRIC MATERIALS; DISTRIBUTION; ELECTRICAL INSULATION; ENERGY DENSITY; RELIABILITY; SYNTHESIS; TITANIUM

Citation Formats

Tuncer, Enis, Cantoni, Claudia, More, Karren Leslie, James, David Randy, Polyzos, Georgios, Sauers, Isidor, and Ellis, Alvin R. Breakdown properties of epoxy nanodielectric. United States: N. p., 2010. Web.
Tuncer, Enis, Cantoni, Claudia, More, Karren Leslie, James, David Randy, Polyzos, Georgios, Sauers, Isidor, & Ellis, Alvin R. Breakdown properties of epoxy nanodielectric. United States.
Tuncer, Enis, Cantoni, Claudia, More, Karren Leslie, James, David Randy, Polyzos, Georgios, Sauers, Isidor, and Ellis, Alvin R. 2010. "Breakdown properties of epoxy nanodielectric". United States. doi:.
@article{osti_991183,
title = {Breakdown properties of epoxy nanodielectric},
author = {Tuncer, Enis and Cantoni, Claudia and More, Karren Leslie and James, David Randy and Polyzos, Georgios and Sauers, Isidor and Ellis, Alvin R},
abstractNote = {Recent developments in polymeric dielectric nanocomposites have shown that these novel materials can improve design of high voltage (hv) components and systems. Some of the improvements can be listed as reduction in size (compact hv systems), better reliability, high energy density, voltage endurance, and multifunctionality. Nanodielectric systems demonstrated specific improvements that have been published in the literature by different groups working with electrical insulation materials. In this paper we focus on the influence of in-situ synthesized titanium dioxide (TiO{sub 2}) nanoparticles on the dielectric breakdown characteristics of an epoxy-based nanocomposite system. The in-situ synthesis of the particles creates small nanoparticles on the order of 10 nm with narrow size distribution and uniform particle dispersion in the matrix. The breakdown strength of the nanocomposite was studied as a function of TiO{sub 2} concentration at cryogenic temperatures. It was observed that between 2 and 6wt% yields high breakdown values for the nanodielectric.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2010,
month = 1
}

Conference:
Other availability
Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that hold this conference proceeding.

Save / Share:
  • Physical properties of a nanodielectric composed of in situ synthesized titanium dioxide (TiO{sub 2}) nanoparticles ({le} 5 nm in diameter) and a cryogenic resin are reported. The dielectric losses were reduced by a factor of 2 in the nanocomposite, indicating that the presence of small TiO{sub 2} nanoparticles restricted the mobility of the polymer chains. Dielectric breakdown data of the nanodielectric was distributed over a narrower range than that of the unfilled resin. The nanodielectric had 1.56 times higher 1% breakdown probability than the resin, yielding 0.64 times thinner insulation thickness for the same voltage level, which is beneficial inmore » high voltage engineering.« less
  • This study employed various butadiene-acrylonitrile rubbers and showed that both the functionality of the end groups and the acrylonitrile content have a strong influence on the microstructure and the interfacial bonding that are observed in the resulting rubber-toughened epoxy. For the rubbers examined, significant toughening is recorded only when the rubber forms a separate phase in the epoxy matrix with a particle size on the order of micrometers. These microstructural features are affected by both the functionality of the end groups and the acrylonitrile content of the rubber employed. However, once phase separation of the rubber has been achieved tomore » give particles on the order of micrometers in size, then the interfacial bonding between the rubber particles and the epoxy matrix has only a small effect on the fracture properties of the rubber-toughened epoxy polymers. 28 refs., 6 figs., 3 tabs.« less
  • Effects of through-the-thickness stitching on the impact damage resistance, impact damage tolerance and interlaminar fracture toughness (Mode I and Mode II) of plain woven and uniweave textile graphite/epoxy laminates are investigated. The laminates were manufactured using resin-infusion-molding and resin-transfer-molding processes. Kevlar{reg_sign} and glass yarns of different yam numbers were used for stitching. Static Indentation-flexure (SI), Compression-After-Impact (CAI), Double-Cantilever-Beam (DCB) and End-Notched-Flexure (ENF) tests were conducted. Stitching did not have any significant effect on impact damage resistance. However, stitching leads to significant improvement (25-40%) in impact damage tolerance as measured by CAI strength and impact damage area. Mode I fracture toughnessmore » as characterized by critical strain energy release rate (G{sub Ic}) was found to increase by at least an order higher (15--30 times) than the unstitched laminates. Mode II fracture toughness (G{sub Ic}) increased by 5--15 times over the unstitched laminates. New methods to estimate Mode 11 critical strain energy release rate in the stitched laminates are presented.« less
  • The mechanical behavior of quasi-isotropic and unidirectional epoxy-matrix carbon-fiber laminated composites subjected compressive loading at strain rates of 10{sup {minus}3} and 2000 s{sup {minus}1} are described. Failure in the studied composites was dominated by delamination which proceeded by brittle fracture of the epoxy-matrix. The matrix-fiber bonding in these composites is very strong and prevented the occurrence of significant fiber-pullout. The mode I delamination strain energy release rate of the unidirectional composites was determined using the double cantilever beam and hole in plate compression method. The DCB method indicated a significant R curve effect attributed to fiber bridging while the presentlymore » available hole in plate analytical methods show questionable validity for highly anisotropic materials.« less
  • Fatigue tests at 5 Hz, ambient temperature, were performed until rupture on carbon fiber unidirectional composites based on two types of matrix: epoxy network (Tg = 483 K) and semicrystalline polyetheretherketone (PEEK). Similar tests were also made on the unreinforced matrices. All the fatigue test made on pure matrices were run in the alternate mode. The fatigue tests on composites has been run in the ondulated mode with a minimum/maximum stress ratio of 0.1. Two loading configurations, respectively 3 and 4 points bending, were compared in conditions where flexural and shear stress-levels were identical for both materials. The results canmore » be summarized as follows: for both composites, there is a wide scatter of lifetimes, typically from 10{sup 3} to 10{sup 5} cycles for stress levels ranging from 1700 to 2000 MPa in the 3 points bending configuration and 1300-1700 MPa in the 4 points configuration. The scatter is presumably due to a random crack initiation by fiber rupture. The systematic difference between 3 and 4 points bending was previously observed in the case of glass fiber composites and interpreted in terms of difference of loaded volume. These interpretations are supported by SEM observations revealing also the existence of a preferential initiation in the interply region. Testing in pure matrix samples reveals a big difference between both polymers since, in the 10{sup 3} 10{sup 5} cycles lifetime interval, the stress varies between 105 and 80 MPa for PEEK and 50 and 30 MPa for epoxy. It appears thus that, in the case under study, the intrinsic fatigue behavior of the matrix plays practically no role on the composite fatigue.« less