Use of dielectric spectroscopy to assess adhesively bonded composite structures, Part II: Dielectric study

A study of the sorption and desorption of moisture in a structural adhesively bonded composite structure using low- and high-frequency dielectric spectroscopy is reported when the adhesive is subjected to a hot and wet environment. As water penetrates the structure, variations in the dielectric permittivity and dielectric loss can be used to understand the nature of the absorption process. A new dielectric tool is introduced to aid interpretation of the dielectric data based on the Kirkwood-Fröhlich equation of the dipolar activity. The data are correlated with gravimetric and dynamic mechanical thermal analysis of the adhesive during exposure to moisture reported in Part I of this series of three articles.

[1]  N. E. Hill,et al.  Dielectric properties and molecular behaviour , 1969 .

[2]  T. Saunders,et al.  Mechanism of the tertiary amine‐catalyzed dicyandiamide cure of epoxy resins , 1967 .

[3]  R. Pethrick,et al.  Real-time dielectric studies of network formation in thermally activated epoxy-amine and isocyanate-triol systems , 1995 .

[4]  Michael J. Adamson,et al.  Thermal expansion and swelling of cured epoxy resin used in graphite/epoxy composite materials , 1980 .

[5]  Y. Balagurunathan,et al.  Insight into redox-regulated gene networks in vascular cells , 2007, Bioinformation.

[6]  H. Thomas Hahn,et al.  Residual Stresses in Polymer Matrix Composite Laminates , 1976 .

[7]  Shin Yagihara,et al.  Dielectric relaxation time and structure of bound water in biological materials , 1987 .

[8]  G. G. Stokes.  "J." , 1890, The New Yale Book of Quotations.

[9]  N. Shinyashiki,et al.  Dielectric study of water structure in polymer solution , 1994 .

[10]  G. P. Johari,et al.  Physico-chemical aspects of dielectric and thermodynamic changes during high-temperature polymerization and their technical use , 1999 .

[11]  Z. Kolek.  Characterization of water penetration inside organic coatings by capacitance measurements , 1997 .

[12]  S. Mashimo,et al.  In vivo dielectric analysis of free water content of biomaterials by time domain reflectometry. , 1997, Analytical biochemistry.

[13]  L. Nicolais,et al.  Characterization of the morphological fine structure of commercial thermosetting resins through hygrothermal experiments , 1985 .

[14]  S. Mashimo,et al.  High order and local structure of water determined by microwave dielectric study , 1993 .

[15]  A. Tourlidakis,et al.  The design and analysis of pipe diffusers for centrifugal compressors , 2000 .

[16]  R. M. Scott.  ‘Plastics’ , 1952, Commodity Derivatives.

[17]  Time domain reflection dielectric spectroscopy for durability assessment of adhesively bonded composite structures , 2000 .

[18]  I. H. Marshall,et al.  Non-destructive Testing of Fibre-reinforced Plastics Composites: Volume 1. Edited by John Summerscales, 1987. Elsevier Applied Science Publishers, London. ISBN 1 85166 093 3. Price: £42·00 , 1988 .

[19]  William M. Banks,et al.  High-frequency dielectric investigations of adhesive bonded structures , 1995 .

[20]  H. Leidheiser,et al.  High-frequency time-domain dielectric spectrometer for the determination of water in polymer coatings on metal substrates , 1985 .

[21]  Richard A. Pethrick,et al.  High frequency electrical measurements of adhesive bonded structures : An investigation of model parallel plate waveguide structures , 1997 .

[22]  P. Hedvig.  Electrical properties of polymers , 1977, Digest of Literature on Dielectrics Volume 42 1978.

[23]  F. Ainger,et al.  Improvements to Microcircuit Reliability by the Use of Inhibited Encapsulants , 1984 .

[24]  K. Dušek.  Epoxy Resins and Composites III , 1986 .

[25]  A. Maradudin,et al.  Theory of dielectrics , 1949 .

[26]  Graham Williams,et al.  Anelastic and Dielectric Effects in Polymeric Solids , 1991 .