The Cure Cycle of PMR-15 as Studied by in situ Infrared Spectroscopy

Abstract

The results from two new applications of infrared spectroscopy to the study of PMR-15 and a model system derived from it (MDA/NE) are presented. Simultaneous reaction monitoring and evolved gas analysis (SIRMEGA) experiments allow the cure chemistry to be followed with precision and show a good correlation between the changes observed in the spectra and the evolved gases for the imidization step. For the cyclopentadiene evolution step, the changes in the infrared spectrum are less marked. The results for both PMR-15 and MDA/NE were surprising in that the application of pressure appears to stop the reaction. It is suggested that under pressure the retro Diels-Alder reaction is suppressed and that other types of cross-links are generated.

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References

1. D. Wilson , J.K. Wells , J.N. Hay , D. Lind , G.A. Owens and F. Johnson , SAMPE J., May/June, 35 (1987).

2. J.N. Hay , J.D. Boyle , P.G. James , J.R. Walton and D. Wilson , in Polyimides: Materials, Chemistry and Characterisation, C. Feger , M.M. Khojasteh and J.E. McGrath (Eds), Elsevier, Amsterdam, p. 305 (1989).

3. J.N. Hay , J.D. Boyle , S.F. Parker and D. Wilson , Polymer, 30, 1032 (1989).

4. P.R. Young and A.C. Chang , J. Heterocycl. Chem., 20, 177 (1983).

5. N. Odagiri , T. Yamashita and K. Tobukuro , Proc. Composites ‘86—Recent Advances in Japan and the United States, K. Kawata , S. Umekawa and K. Kobayashi (Eds), Japan Society for Composite Materials, Tokyo 1986, p. 53.

6. P.R. Young and A.C. Chang , Proc. Natl. SAMPE Exhib., Adv. Technol. Mater. Proc, 30, 889 (1985).

7. D. Garcia and T.T. Serafini , J. Polym. Sci., Phys., 25, 2275 (1987).