Abstract
The thermal degradation of foamed polystyrene patterns in the expendable pattern casting (EPC) process has been studied. Various physical transitions that may occur during the degradation of the polymer have been determined with scanning electron microscopy, differential scanning calorimetry and thermogravimetric analysis. The effects of polymer density and bead structure on the degradation characteristics have been investigated. The results indicate that, when exposed to elevated temperatures, the polymer beads collapse at about 110–120 °C. The collapsed beads melt at 160 °C, and start to vaporize at temperatures greater than about 275 °C. Complete volatilization occurs in the temperature range 460–500 °C. The heat of degradation of expanded polystyrene has been estimated to be at the order of 912 Jg−1.
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References
A. J. Clegg, Foundry Trade J. Int. 9 (1986) 51.
H. J. Heine, Foundry Man. & Tech. 114 (1986) 36.
S. Shivkumar and B. Gallois, Trans. Am. Foundrymen's Soc. 95 (1987) 791.
Idem, ibid. 95 (1987) 801.
L. Wang, S. Shivkumar and D. Apelian, ibid. 98 (1990) 923.
S. Shivkumar, L. Wang and D. Apelian, J. of Met. 42 (1990) 38.
J. F. Rudd, in “Polymer Handbook”, edited by J. Brandrup and E. H. Immergut (Wiley, New York, 1989) p. V-82.
R. H. Boundy and R. F. Boyer, “Styrene, Its Polymers, Copolymers and Derivatives” (Reinhold Publishing Corporation, New York, 1952) 43–57.
S. Mehta, M.Sc. Thesis, Worcester Polytechnic Institute, Worcester, MA (1992).
M. Guaita, Brit. Polym. J. 18 (1986) 226.
J. L. Gurman, L. Baier and B. C. Levin, Fire & Mater. 11 (1987) 109.
A. Guyot, Polym. Deg. & Stab. 15 (1986) 219.
S. Shivkumar, Trans. Am. Foundrymen's Soc. 101 (1993) in press.
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Mehta, S., Biederman, S. & Shivkumar, S. Thermal degradation of foamed polystyrene. JOURNAL OF MATERIALS SCIENCE 30, 2944–2949 (1995). https://doi.org/10.1007/BF00349667
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DOI: https://doi.org/10.1007/BF00349667