Abstract
Kinetic and viscosity relations for polyurethane network polymerization were analyzed. A rigid foam formulation consisting of a polymeric isocyanate (functionality ca. 2.7) and a polyether polyol (functionality ca. 4.5), was selected. The kinetics were studied with adiabatic temperature rise and chemical techniques. An overall second-order reaction and an activation energy, E=51.2 kJ mol−1, were obtained. The viscosity rise was correlated with the reaction extent and the weight average molecular weight. The dependence of viscosity on the latter was of mth order, with m greater than 3.4. This high parametric sensitivity is associated with the formation of branched structures from the beginning of the reaction.
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A. J. Rojas, H. E. Adabbo, and R. J. J. Williams, Polym. Eng. Sci., 21, 634 (1981).
J. M. Castro and C. W. Macosko, Studies of mold filling and curing in the reaction injection molding (RIM) process, AIChE J., in press.
P. J. Flory, J. Am. Chem. Soc., 63, 3091 (1941).
J. M. Castro and C. W. Macosko, “Rheology of Polyurethane Reaction Injection-Molding Systems,” Proceedings of 3rd International Meeting on Polymer Science and Technology, La Plata, Argentina, 1981, p 276.
S. D. Lipshitz, F. G. Mussatti, and C. W. Macosko, SPE ANTEC Tech. Papers, 21, 239 (1975).
S. D. Lipshitz and C. W. Macosko, Polym. Eng. Sci., 16, 803 (1976).
J. M. Castro, F. López Serrano, R. E. Camargo, C. W. Macosko, and M. Tirrell, J. Appl. Polym. Sci., 26, 2067 (1981).
A. J. Rojas, J. Borrajo, and R. J. J. Williams, Polym. Eng. Sci., 21, 1122 (1981).
E. B. Richter and C. W. Macosko, Polym. Eng. Sci., 18, 1012 (1978).
C. W. Macosko and D. R. Miller, Macromolecules, 9, 199 (1976).
T. G Fox and G. C. Berry, Adv. Polym. Sci., 5, 261 (1968).
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Reboredo, M., Rojas, A. & Williams, R. Kinetic and Viscosity Relations for Thermosetting Polyurethanes. Polym J 15, 9–14 (1983). https://doi.org/10.1295/polymj.15.9
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DOI: https://doi.org/10.1295/polymj.15.9