Summary
Glassy liquid crystalline poly(p-hydroxy-benzoic acid-co-ethylene terephthalate) is after rapid cooling from temperatures above Tg in a non-equilibrium state and exhibits physical ageing. It is shown that enthalpy and volume decrease with increasing annealing time. At the same undercooling, with respect to middle temperature of the major glass transition (Tgl), the rate of the equilibration process is significantly slower in the studied polymer than in an ordinary glassy amorphous polymer. The presence of a constraining ETP-rich phase exhibiting a 25 K higher glass temperature than Tgl may be the cause for this retarded enthalpy relaxation.
Similar content being viewed by others
References
Warner SB, Macromolecules (1980) 13:450
Struik L C E (1978), Physical aging in amorphous polymers and other materials, Elsivier Sci. Publ., Amsterdam
Hutchinson J M and Kovacs A J (1976), in “The structure of non-crystalline materials”, proceedings of the symposium in Cambridge, U.K. Ed. P.H. Gaskell, Taylor and Francis Ltd, London, p. 167
Kovacs A J, Hutchinson J M and Aklonis J J (1976), in “The structure of non-crystalline materials”, proceedings of the symposium in Cambridge, U.K., Ed. P.H. Gaskell, Taylor and Francis Ltd, London, p. 153
Chai C K and McCrum N G, Polymer (1980) 21:706
Hutchinson J M and Bucknall C B, Polym. Eng. Sci. (1980) 20:173
Struik L C E, Polymer (1987) 28:1521
Struik L C E, Polymer (1987) 28:1534
Hedmark P G, Jansson J-F, Hult A, Lindberg H and Gedde U W, J. Appl. Polym. Sci. (1987) 34:743
Gedde U W, Buerger D and Boyd R H, Macromolecules (1987) 20:988
Amundson K R, Kalika D S, Shen M-R, Yu X-M, Denn M-M and Reimer J A, Mol. Cryst. Liq. Cryst. (1987) 153:271
Jackson Jr. W J and Kuhfuss H F, J. Polym. Sci., Polym. Chem Ed. (1976) 14:2043
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Hedmark, P.G., Dick, R.W.R. & Gedde, U.W. Physical ageing in glassy liquid crystalline poly(p-hydroxy-benzoic acid-co-ethylene terephtalate). Polymer Bulletin 23, 83–88 (1990). https://doi.org/10.1007/BF00983968
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00983968