A Study on Reaction Kinetics of PTMG/TDI Prepolymer with MOCA by Non-Isothermal DSC

  • Ahn, WonSool (Department of Chemical Engineering, Keimyung University) ;
  • Eom, Seong-Ho (Department of Chemical Engineering, Keimyung University)
  • Received : 2015.03.10
  • Accepted : 2015.04.16
  • Published : 2015.06.30


A study on reaction kinetics for a PTMG/TDI prepolymer with 2,2'-dichloro-4,4'-methylenedianiline (MOCA), of which formulations may be generally used for fabricating high performance polyurethane elastomers, was peformed using non-isothermal differential scanning calorimetry (DSC). A number of thermograms were obtained at several constant heating rates, and analysed using Flynn-Wall-Ozawa (FWO) isoconversional method for activation energy, $E_a$ and extended-Avrami equation for reaction order, n. Urea formation reaction of the present system was observed to occur through the simple exothermic reaction process in the temperature range of $100{\sim}130^{\circ}C$ for the heating rate of $3{\sim}7^{\circ}C/min$. and could be well-fitted with generalized sigmoid function. Though activation energy was nearly constant as $53.0{\pm}0.5kJ/mol$, it tended to increase a little at initial stage, but it decreases at later stage by the transformation into diffusion-controlled reaction due to the increased viscosity. Reaction order was evaluated as about 2.8, which was somewhat higher than the generally well-known $2^{nd}$ order values for the various urea reactions. Both the reaction order and reaction rate explicitly increased with temperature, which was considered as the indication of occurring the side reactions such as allophanate or biuret formation.


  1. A. L. Daniel-da-Silva, J. C. Moura Bordado, and J. M. Martin- Martinez, "Moisture Curing Kinetics of Isocyanate Ended Urethane Quasi-Prepolymers Monitored by IR Spectroscopy and DSC", J. Appl. Polym. Sci., 107, 700 (2008).
  2. K. Gisselfalt and B. Helgee, "Effect of Soft Segment Length and Chain Extender Structure on Phase Separation and Morphology in Poly(urethane urea)s", Macromol. Mater. Eng., 288, 265 (2003).
  3. X.-D. Chen, N.-Q. Zhou1, and H. Zhang, "Preparation and properties of cast polyurethane elastomers with molecularly uniform hard segments based on 2,4-toluene diisocyanate and 3,5-dimethylthioltoluene diamine", J. Biomed. Sci. Eng., 2, 245 (2009).
  4. D. K. Chattopadhyay and K. V. S. N. Raju, "Structural engineering of polyurethane coatings for high performance applications", Prog. Polym. Sci., 32, 352 (2007).
  5. C. M. Thompson, S. G. Taylor, and W. W. Mcgee, "Gel permeation chromatographic analysis of polyurethane prepolymer synthesis kinetics. I. The effect of catalyst", J. Polym. Sci. Part A: Polym. Chem., 28, 333 (1990).
  6. S. Parnell, K. Min, and M. Cakmak, "Kinetic studies of polyurethane polymerization with Raman spectroscopy", Polymer, 44, 5137 (2003).
  7. V. W. A. Verhoeven, A. D. Padsalgikar, K. J. Ganzeveld, and L. P. B. M. Janssen, "A kinetic investigation of polyurethane polymerization for reactive extrusion purposes", J. Appl. Polym. Sci., 101, 370 (2006).
  8. C. Yanjun, H. Ling, W. Xinling, and T. Xiaozhen, "Evaluation of the cure kinetics of isocyanate reactive hot-melt adhesives with differential scanning calorimetry", J. Appl. Polym. Sci., 89, 2708 (2003).
  9. T. Ozawa, "Kinetics of non-isothermal crystallization", Polymer, 12, 150 (1971).
  10. T. Ozawa, "Non-isothermal kinetics and generalized time", Thermochim. Acta., 100, 109 (1986).
  11. M. Popovic, J. Budinski-Simendic, M. Jovicic, J. Mursics, M. Điporovic-Momcilovic, J. Pavlicevic, and I. Ristic, "Curing kinetics of two commercial urea-formaldehyde adhesives studied by isoconversional method", Hem. Ind., 65, 717 (2011).
  12. L. Xiaolie, L. Jin, and M. Dezhu, "Exploration of the Difference of Reaction Rates for Polyester and Polyether Urethane Prepolymers with 3,3'-Dichloro-4,4'-Diaminodiphenylmethane", J. Appl. Polym. Sci., 67, 467 (1996).
  13. L. I. Majoros, B. Dekeyser, R. Hoogenboom, M. W. M. Fijten, J. Geeraert, N. Haucourt, and U. S. Schubert, "Kinetic Study of the Polymerization of Aromatic Polyurethane Prepolymers by High-Throughput Experimentation", J. Polym. Sci. Part A: Polym. Chem., 48, 570 (2010).