Abstract
An understanding of the chemistry of a magnetic memory disk coating system, and an ability to manipulate this chemistry through formulation and processing, is essential in the attainment of optimal performance properties. In this paper we discuss the chemical and physical phenomena associated with the cure of an epoxy-phenolic binder system filled with γ-Fe2O3. The magnetic coating formulation consists of a binder system containing a DGE-BPA epoxy, an allyl capped resole phenolic, poly(vinyl methyl ether), and a dispersing agent, plus a filler system consisting of the magnetic particle and alumina. The chemical and physical phenomena occurring during cure have been characterized by a number of analytical techniques, including thermal analysis (DMA, DSC, and TGA) and spectroscopic analysis (NMR, FTIR, and TGA/MS). Using these techniques, the cure of this epoxy-phenolic coating is shown to involve initial crosslinking via non-oxidative reactions, followed by further crosslinking via oxidative reactions. Decomposition of key binder components accompanies the crosslinking to produce a high Tg, microporous coating.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
J. M. Harker, D. W. Brede, R. E. Pattison, G. R. Santana, and L. G. Taft, IBM J. Res. Develop., 25(5), 677 (1981).
R. B. Mulvany and L. H. Thompson, IBM J. Res. Develop., 25(5), 711 (1981).
R. B. Prime, J. M. Burns, M. L. Karmin, C. H. Moy and H.-B. Tu, J. Coat. Tech., 60 (761),55 (1988).
D. D. Johnson, R. Flores and M. J. Vogel, U.S. Patent 3,058,844, 1962.
R. B. Prime, J. Thermal Anal., 31, 1091 (1986).
L. T. Manzione, J. K. Gillham and C. A. McPherson, J. Appl. Polym. Sci., 26, 889 (1981).
R. B. Prime, Proceedings of the 14th NATAS Conference, 137 (1985).
J.M. Burns and M.L. Karmin, Proceedings of the 13th NATAS Conference, 369 (1984).
R.B. Prime and B. Shushan, Anal. Chem., in press.
L. Shechter and J. Wynstra, Ind. Eng. Chem., 48, 86 (1956).
The Fe2O3 changes from brown to black, accompanied by an increase in coercivity.
V.M. DePalma, M.F. Doerner and A. W. Ward, IEEE Trans. Mag., Mag-18, 1083 (1982).
The variance in degree of allyl capping was determined via 13C NMR using an inverse gated heteronuclear decoupling method.
R.B. Prime, E.F. Whelihan and J.M. Burns, Soc. Plast. Eng. Tech. Papers, 34, 1268 (1988).
D.H. Soloman and D.G. Hawthorne, “Chemistry of Pigments and Fillers”, Wiley-Interscience, New York, 1983.
R.M. Roberts, J.C. Gilbert, L.B. Rodewald, and A.S. Wingrove, “An Introduction to Modern Experimental Organic Chemistry”, Holt, Rinehart and Winston, New York, 1969.
This was shown via the absence of significant adsorption of radiolabeled PVME from a mixture of Fe2O3 and PVME in the magnetic coating formulation solvents.
T.C. Patton, “Paint Flow and Pigment Dispersion”, Wiley-Interscience, New York, 1979.
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 1989 Plenum Press, New York
About this chapter
Cite this chapter
Burns, J.M., Prime, R.B., Barrall, E.M., Oxsen, M.E., Wright, S.J. (1989). Chemistry of an Epoxy-Phenolic Magnetic Disk Coating. In: Mittal, K.L. (eds) Polymers in Information Storage Technology. Springer, Boston, MA. https://doi.org/10.1007/978-1-4613-0843-0_18
Download citation
DOI: https://doi.org/10.1007/978-1-4613-0843-0_18
Publisher Name: Springer, Boston, MA
Print ISBN: 978-1-4612-8110-8
Online ISBN: 978-1-4613-0843-0
eBook Packages: Springer Book Archive