Abstract
The glass transition temperatures Tg of monodispersed polystyrenes possessing different number-averaged molecular weights Mn were determined by high pressure DTA of up to 500 MPa. The measurements were performed using samples glassified at a cooling rate of 20 K/min−1 under differing pressures. Tg was satisfactorily fitted against P according to the Simon-type equation, which is usually applied to the relation between melting points and P. The linear relation of Tg against Mn−1 was found to hold even under high pressure. The slope of this relation increased from 0.98×105 K at atmospheric pressure to 1.19×105 K at 500 MPa. When the slope was analyzed by means of Bueche’s model, the excess free volume of the chain ends decreased with increasing pressure and seemed to have an asymptotic value above 350 MPa, which was one-third of the value at atmospheric pressure.
Similar content being viewed by others
Article PDF
References
T. G. Fox and P. J. Flory, J. Appl. Phys., 21, 581 (1950).
T. G. Fox and P. J. Flory, J. Polym. Sci., 14, 315 (1954).
L. A. Wall, Roestamjah, and M. H. Aldridge, J. Res. Natl. Bur. Std., 78A, 447 (1974).
M. J. Richardson and N. G. Savill, Polymer, 18, 3 (1977).
M. J. Richardson and N. G. Savill, Polymer, 16, 753 (1975).
K. Takamizawa and H. Toratani, Thermochim. Acta, 163, 325 (1990).
K. Takamizawa and F. E. Karasz, presented at the State-of-the-Art of Thermal Analysis, NBS, May l 979. Experimental data were cited in ref 7.
K. Takamizawa, Y. Nagao, and Y. Urabe, Kyushu Daigaku Sogorikogakukenkyuka Hokoku (Eng. Sci. Reports, Kyushu Univ.), 6, 163 (1985).
K. Takamizawa and H. Toratani, Polymer, 33, 1333 (1992).
F. Bueche, “Physical Properties of Polymers,” Interscience, New York, N.Y., 1962.
T. Somcynsky and D. Patterson, J. Polym. Sci., 62, 151 (1962).
J. H. Gibbs and E. A. DiMarzio, J. Chem. Phys., 28, 373 (1958).
K. Takamizawa, Y. Nagao, D. Irii, and Y. Urabe, Thremochim. Acta, 88, 205 (1985).
K. Takamizawa, Thermochim. Acta, 25, 1 (1978).
H.-J. Oels and G. Rehage, Macromolecules, 10, 1036 (1977).
K. Takamizawa, A. Ohno, and Y. Urabe, Polym. J., 7, 342 (1975).
K. Takamizawa, H. Toratani, and F. E. Karasz, Thermochim. Acta, submitted.
A. Quach and R. Simha, J. Appl. Phys., 42, 4592 (1971).
S. Ichihara, A. Komatsu, and T. Hata, Polym. J., 2, 650 (1971).
J. R. Stevens, R. W. Coakley, K. W. Chau, and J. L. Hunt, J. Chem. Phys., 84, 1006 (1986).
G. Pezzin, F. Zilio-Grandi, and P. Sanmartin, Eur. Polym. J., 6, 1053 (1970).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Toratani, H., Takamizawa, K. Effect of Pressure on the Relation between Glass Transition Temperature and Molecular Weight for Monodispersed Polystyrenes. Polym J 26, 797–803 (1994). https://doi.org/10.1295/polymj.26.797
Issue Date:
DOI: https://doi.org/10.1295/polymj.26.797