Hostname: page-component-cd9895bd7-fscjk Total loading time: 0 Render date: 2024-12-28T16:07:23.308Z Has data issue: false hasContentIssue false

The strength, fracture, and chemical changes of poly-(p-phenylene benzobisthiazole) after exposure to molten and vapor deposited aluminum

Published online by Cambridge University Press:  31 January 2011

K.E. Newman
Affiliation:
The Department of Materials Science and Engineering, Metals Science and Engineering Program, The Pennsylvania State University, University Park, Pennsylvania 16802
P. Zhang
Affiliation:
The Department of Materials Science and Engineering, Polymer Science Program, The Pennsylvania State University, University Park, Pennsylvania 16802
L.J. Cuddy*
Affiliation:
The Department of Materials Science and Engineering, Metals Science and Engineering Program, The Pennsylvania State University, University Park, Pennsylvania 16802
D.L. Allara*
Affiliation:
The Department of Materials Science and Engineering, Polymer Science Program, The Pennsylvania State University, University Park, Pennsylvania 16802
*
a)Authors to whom correspondence should be directed.
a)Authors to whom correspondence should be directed.
Get access

Abstract

The tensile properties, fracture behavior, and surface chemical composition of the rigid-rod heterocyclic aromatic polymer fiber poly-(p-phenylene benzobisthiazole), PBT, have been measured as a function of contact with nominally zero valent aluminum overlayers. The samples were produced by immersion of suitable fiber or film specimens in a molten aluminum-12.7 wt. % silicon alloy or by aluminum-vapor deposition followed by heat treatment. The strength of uncoated PBT fiber was 3.0 GPa. After 5 min immersion in the molten aluminum alloy, strengths drop to 80% and 25% of the uncoated fiber values for 600°and 700 °C immersion, respectively. Fiber strengths after aluminum immersion are from zero to 20% lower than the strength for corresponding uncoated fibers heated at an equivalent temperature in argon. Coated fibers exhibit tensile strengths after heating intermediate to similarly heated uncoated or immersed fibers. For all types of samples, the fiber fracture mode changes from fibrillar at failure strengths >1.9 GPa (independent of the environment) to planar at failure strengths <1.9 GPa. X-ray photoelectron spectroscopy of PBT fiber and film surfaces indicates oxidation of the polymer surface has occurred, most likely during fabrication of the fiber or film. The oxygen content of the surface layer is decreased when the film is immersed in molten aluminum-silicon alloy. The lack of corresponding changes in the relative intensities of the polymer C, S, or N photoemission peaks after this immersion suggests that the surface oxidized layer plays some role in protecting the polymer from degradation by molten aluminum. These results strongly suggest that it is possible to fabricate low-density, high-strength PBT/metal composites by liquid aluminum alloy infiltration if the melt temperature is kept below 680 °C and the contact time with molten aluminum kept below 3 min.

Type
Articles
Copyright
Copyright © Materials Research Society 1991

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1.Baker, A.A., Shipman, C., and Jackson, P.W., Fiber Sci. Technol. 5, 213 (1972).CrossRefGoogle Scholar
2.Allen, S. R., Farris, R. J., and Thomas, E. L., J. Mater. Sci. 20, 2727 (1985).CrossRefGoogle Scholar
3.Adams, W.W. and Eby, R.K., MRS Bull. XII (8) (Nov./Dec. 1987).Google Scholar
4.Feldman, L., Farris, R. J., and Thomas, E. L., J. Mater. Sci. 20, 2719 (1985).CrossRefGoogle Scholar
5.Wolfe, J. F., “Polybenzothiazole and Polybenzoxazoles”, in Encyclopedia of Polymer Science and Engineering, edited by Mark, H. and Overberger, M. (Wiley & Sons, New York, 1981), Vol. 11.Google Scholar
6.Jenekhe, S. A., Johnson, P. O., and Agrawal, A. K., Macromol. 22, 3309 (1989).CrossRefGoogle Scholar
7.Odell, J.A., Keller, A., Atkins, E.D.T., and Miles, J., J. Mater. Sci. 16, 3309 (1981).CrossRefGoogle Scholar
8.Day, R. J., Robinson, I. M., Zakikhani, M., and Young, R. J., Polymer 28, 1388 (1987).CrossRefGoogle Scholar
9.Allen, S. R., Farris, R. J., and Thomas, E. L., J. Mater. Sci. 20, 4583 (1985).CrossRefGoogle Scholar
10.Wolfe, J.F. and Arnold, F.E., Macromol. 14, 909 (1981).CrossRefGoogle Scholar
11.Wolfe, J.F., Loo, B.H., and Arnold, F.E., Macromol. 14, 916 (1981).Google Scholar
12.Allen, S. R., Filippov, A. G., Farris, R. J., and Thomas, E. L., J. Appl. Polym. Sci. 26, 291 (1981).CrossRefGoogle Scholar
13.Das, A.A. and Chatterjee, S., The Metallurgist and Materials Technologist, 137 (March 1981).Google Scholar
14.Chow, T. W., Kelly, A., and Okura, A., Composite, 187 (July 1985).CrossRefGoogle Scholar
15.Newman, K. E. and Zhang, P. (unpublished results).Google Scholar
16. The biaxial orientation is produced by extruding the dope through counter-rotating concentric cylinders that produce shear in the polymer solution and thereby yield the ±23° molecular orientation. Films produced in this fashion are then placed in a water bath where coagulation and removal of all residual solvent occurs, followed by drying at 100–250 °C. Foster Miller, Inc., U.S. Patent Number 4973442.Google Scholar
17.Savitsky, A. and Golay, M.J.E., Anal. Chem. 36, 1627 (1964).CrossRefGoogle Scholar
18.Baker, S. J. and Bonfield, W., J. Mater. Sci. 13, 1329 (1978).CrossRefGoogle Scholar
19.Jackson, P. W., Metals Eng. Quarterly, 22 (August 1969).Google Scholar
20.Honjo, K. and Shindo, A., J. Mater. Sci. 21, 2043 (1986).CrossRefGoogle Scholar
21.Newman, K. E. (unpublished data).Google Scholar
22.Epp, J., Zhang, P., and Aliara, D. L. (unpublished results).Google Scholar
23.Burkstrand, J. M., J. Appl. Phys. 52, 4795 (1985).CrossRefGoogle Scholar
24.Vasile, M.J. and Bachman, B.J., J. Vac. Sci. Technol. A7, 2992 (1989).CrossRefGoogle Scholar
25.Tsai, S.D., Ph.D. Thesis, The University of Texas at Austin (1980).Google Scholar
26.Ho, P.S., Hahn, P.O., Bartha, J.W., Rubloff, G.W., and Silverman, B.D., J. Vac. Sci. Technol. A3 (3), 739 (May–June 1985).CrossRefGoogle Scholar
27.Tromp, R. M., Legoues, F., and Ho, P. S., J. Vac. Sci. Technol. A3 (3), (May–June 1985).Google Scholar
28.Hahn, P. O., Rubloff, G.W., and Ho, P. S., J. Vac. Sci. Technol. A2 (2), 756 (April–June 1984).CrossRefGoogle Scholar
29.Jordan, J.L., Sanda, P.N., Morar, J.F., Kovac, C.A., Himpsel, F.J., and Poliak, R.A., J. Vac. Sci. Technol. A4 (3), 1046 (May–June 1986).CrossRefGoogle Scholar