Processing-structure relationships for multiphase epoxy matrix systems
- 38 Downloads
- 1 Citations
Abstract
A styrene-modified diglycidyl ether of bisphenol-A (DGEBA) epoxy system cured with trimellitic anhydride (TMA) has been investigated to explore processing and structure relationships. During cure, the reactive styrene precipitated with polymerization into phase domains separate from the epoxy phase. Dynamic mechanical analysis and microscopy studies were performed to gain insight to matrix structure. The DMA studies showed that the styrenemodified epoxy system after cure exhibited two partially overlapped but distinct relaxation peaks, which are associated with the Tgs of the polystyrene and epoxy phases. The glass transition of the polystyrene phase was shown to be broadened and the Tg to depend strongly on processing temperature profiles. While the Tg of the epoxy phase increases with curing agent concentrations, the Tg of the polystyrene phase does not. Microscopic studies showed that the styrene-modified system exhibited a rougher fracture surface but did not reveal well defined phase domains in which the precipitated polystyrene component was aggregated. Overall, the study has demonstrated correlations of the kinetic factors in controlling the morphology in reactive modifier-epoxy systems.
Keywords
Epoxy Dynamic Mechanical Analysis Epoxy Matrix Diglycidyl Ether DiglycidylPreview
Unable to display preview. Download preview PDF.
References
- 1.
- 2.
- 3.
- 4.
- 5.P. D. Mclean, A. Garton and W. T. K. Stevenson and K. E. Macphee, Polym. Comp. 7 (1987) 330.Google Scholar
- 6.D. A. Shimp, F. A. Hudock and W. S. Bobo, 18th Int. SAMPE Tech. Conf. Ser., (1986) pp. 851.Google Scholar
- 7.
- 8.
- 9.
- 10.
- 11.R. W. Hewitt, Jr, US Patent 4 284 753 (1981).Google Scholar
- 12.O. Olabishi, L. M. Robeson and M. T. Shaw, “Polymer-Polymer Miscibility” (Academic, New York, 1979) Ch. 2Google Scholar
- 13.A. V. Tobolsky, “Properties and Structures of Polymers” (Wiley, New York, 1960) p. 95Google Scholar
- 14.
- 15.D. S. Kaplan, J. Appl. Polym. Sci. 20 (1976) 2615.Google Scholar
- 16.
- 17.
- 18.H. S. Chu and J. C. Seferis, in “TheRole of the Polymeric Matrix in the Processing and Structural Properties of Composites Materials”, edited by J. C. Seferis and L. Nicolais (Plenum, New York, 1983) p. 53.Google Scholar