Skip to main content Accessibility help
×
Home

Macroporous Thermosets via Chemically Induced Phase Separation

  • J. Kiefer (a1), R. Porouchani (a1), D. Mendels (a1), J. B. Ferrer (a1), C. Fond (a2), J. L. Hedrick (a3), H. H. Kausch (a1) and J. G. Hilborn (a1)...

Abstract

We have explored a new technology based on chemically induced phase separation that yields porous epoxies and cyanurates with a closed cell morphology and micrometer sized pores with a narrow pore size distribution. When the precursor monomers are cured in the presence of a low molecular weight liquid, the desired morphology results from a phase separation and a chemical quench. After phase separation, the porosity is achieved by thermal removal of the secondary liquid phase, specifically by diffusion through the crosslinked matrix. In respect to the thermodynamics and kinetics, the origin of the phase separation process can be identified as nucleation and growth. The influence of internal and external reaction parameters, such as chemical nature of the low molecular weight liquid, its concentration and the curing temperature on the final morphology are presented. Thus, the morphology can be controlled ranging from a monomodal to bimodal pore size distribution with pore sizes inbetween 1 to 10 μm. These porous thermosets are characterized by a significantly lower density, without any loss in thermal stability compared to the neat matrix. Such new materials demonstrate great interest for lowering the dielectric constant and for improving the fundamental understanding of the role of voids in stress relaxation and toughening.

Copyright

References

Hide All
1. Hedrick, J. L., Hilbom, J., Palmer, T. D. and Labadie, J. W., J. Polym. Sci., Part A: Polym. Chem. 28 (1990) 2255–68.
2. Hedrick, J. L. and Russell, T. P., MRS Symp. Proc. 274 (1992) 3745.
3. Hedrick, J. L., Charlier, Y. and Russell, T. P., MRS Symp. Proc. 323 (1994) 277
4. Hedrick, J. L., Charlier, Y. and Jerome, R., High Perform. Polym. 7 (1995) 133–47.
5. Hedrick, J. L., Russell, T. P., Labadie, J., Lucas, M. and Swanson, S., Polymer 36 (1995) 2685–97.
6. Leterrier, Y., Manson, J. A. E., Hilborn, J. G., Plummer, C. J. G. and Hedrick, J. L., MRS Symp. Proc. 371 (1995) 487–93.
7. Leterrier, Y., Hilborn, J. G., Plummer, C. J. G. and Hedrick, J. L., MRS Symp. Proc. 371 (1995) 481–8.
8. Balde, J. and Messner, G., Circuit World 14 (1987) 1114.
9. Carter, K. C., Sanchez, M. I., Russell, T. P. and McGrath, J. E., Polym. Mat. Sci. Eng. 72 (1995) 383.
10. Riew, C. K. and Kinloch, A. J., Toughened Plastics: Science and Engineering Adv. Chem. Ser. 233 (1993).
11. Collyer, A. A., Rubber toughened engineering plastics (Chapman&Hall, London, 1994).
12. Pearson, R. and DiBerardino, M., 25th Int. SAMPE Techn. Conf (1993) 502
13. Huang, Y., Hunston, D. L., Kinloch, A. J. and Riew, C. K., Adv. Chem. Ser. 233 (1993) 135.
14. Dompas, D., Groeninckx, G., Isogawa, M., Hasegawa, T. and Kadokura, M.,Polymer 35 (1994) 4750–9.
15. Bubeck, R. A., Buckley, D. J. J., Kramer, E. J. and Brown, H. R., J. Mat. Sci. 26 (1991) 6249–59.
16. Huang, Y. and Kinloch, A. J., J. Mat. Sci. 27 (1992) 2763–9.
17. Huang, Y. and Kinloch, A. J., J. Mat. Sci. Lett. 27 (1992) 2753–62.
18. Guild, F. J. and Kinloch, A. J., J. Mat. Sci. 30 (1995) 1689–97.
19. Mendels, D., Ferrer, J. B., Kiefer, J. and Fond, Ch., Semester project (1996) EPFL, Materials Department, Polymers Laboratory, 1015 Lausanne, Switzerland
20. Huang, Y. and Kinloch, A. J., J. Mat. Sci. Lett. 11 (1992) 484–7.
21. Dompas, D. and Groeninckx, G., Polymer 35 (1994) 4743–9.
22. Lazzeri, A. and Bucknall, C. B., J. Mat. Sci. 28 (1993) 6799–808.
23. Bucknall, C. B., Karpodinis, A. and Zhang, X. C., J. Mat. Sci. 29 (1994) 3377–83.
24. Huang, Y. and Kinloch, A. J., Polymer 33 (1992) 1330–2.
25. Bagheri, R. and Pearson, R. A., Polymer 36 (1995) 4883–5.
26. Pascault, J. P., Macromol. Symp. 93 (1995) 4351.
27. Kiefer, J., Hilborn, J. G., Månson, J.-A. E., Leterrier, Y. and Hedrick, J. L., Macromolecules 29 (1996) to appear
28. Kiefer, J., Hilborn, J. G. and Hedrick, J. L., Polymer 37 (1996) submitted.
29. Porouchani, R., Diploma Work, EPFL (1996), 1015 Lausanne, Switzerland
30. Champétier, G., Buvet, R., Néel, J. and Sigwalt, P., Chimie macromoléculaire (Hermann, Paris, 1972).
31. David, D. J. and Sincock, T. F., Polymer 33 (1992) 4505–14.
32. Kiefer, J., Hilborn, J. G., Hedrick, J. L. and Yoon, D. Y., manuscript in preparation.
33. Hamerton, I., Chemistry and Technology of Cyanate Ester Resins (Blackie Academic & Professionel, Glasgow, 1994).

Related content

Powered by UNSILO

Macroporous Thermosets via Chemically Induced Phase Separation

  • J. Kiefer (a1), R. Porouchani (a1), D. Mendels (a1), J. B. Ferrer (a1), C. Fond (a2), J. L. Hedrick (a3), H. H. Kausch (a1) and J. G. Hilborn (a1)...

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed.