Nanocharacterization of Surface and Interface of Different Epoxy Networks.
Nanocharacterization of Surface and Interface of
Different Epoxy Networks.
(167 K)
Gu, X.; Ho, D. L.; Sung, L. P.; VanLandingham, M. R.;
Nguyen, T.; Raghavan, D.
DD Polymer Interfaces and Thin Films. Materials Research
Society (MRS) Symposium. Proceedings. Volume 710.
2002, Karim, A.; Frank, C. W.; Russel, T. P.; Nealey, P.
F., Editor(s)(s), DD109.1-DD109.6 pp, 2002.
Keywords:
epoxy networks; crosslinking density; amine-cured epoxy;
atomic force microscopy; small angle neutron scattering;
surface and interface
Abstract:
The effect of network changes on the surface and
interface properties of amine-cured epoxy has been
investigated. Samples of different crosslinked epoxies
are prepared by mixing stoichiometrically pure
diglycidyl ether of bisphenol A (n=0.03) with different
ratios of 1,3-bis(aminomethyl)cyclohexane
(terafunctional amine) and cyclohexylmethylamine
(difunctional amine). All samples are cured in CO2-free
air. Both the film surface in contact with air and that
in contact with the silicon substrate (the interface)
are analyzed using atomic force microscopy (AFM) and
nanoindentation. Small angle neutron scattering (SANS),
attenuated total reflection Fourier transform infrared
(ATR-FTIR) spectroscopy, and contact angle measurements,
are used to assist in the interpretation of AFM results.
Substantial morphological and mechanical differences are
observed between the surface and the interface for
different crosslinked epoxies. The findings have strong
implications on the wettablity, adhesion, and durability
of amine-cured epoxies.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899