Effect of Resin/Hardener Stoichiometry on Electrical Behavior of Epoxy Networks

F. N. Alhabill, R. Ayoob, T. Andritsch, A. S. Vaughan

Research output: Contribution to journalArticlepeer-review

41 Citations (Scopus)


By changing the ratio of resin to hardener, a series of epoxy resin samples has been produced with differing network structures and different retained chemical functionalities. The resulting materials were characterized by thermal analysis, dielectric spectroscopy, DC conductivity, and DC and AC breakdown strength measurements, to explore the effect of network structure and chemical composition on molecular dynamics and electrical properties. Differential scanning calorimetry showed that the glass transition temperature is primarily determined by the crosslinking density and indicates that, under the range of conditions employed here, side reactions, such as etherification or homopolarization, are negligible. Conversely, changes in DC conductivity with resin stoichiometry appear to occur as a result of changes in the chemical content of the system, rather than variations in network structure or dynamics. Specifically, we suggest that the DC conductivity is markedly affected by the residual amine group concentration in the system. While DC conductivity and DC breakdown appear broadly to be correlated, AC breakdown results indicated that this parameter does not vary with changing stoichiometry, which suggests that the AC and DC breakdown strengths are controlled by different mechanisms.

Original languageEnglish
Article number8315297
Pages (from-to)3739-3749
Number of pages11
JournalIEEE Transactions on Dielectrics and Electrical Insulation
Issue number6
Publication statusPublished - 1 Dec 2017
Externally publishedYes


Dive into the research topics of 'Effect of Resin/Hardener Stoichiometry on Electrical Behavior of Epoxy Networks'. Together they form a unique fingerprint.

Cite this