The time-temperature equivalence equation is deduced simply in view of the transition kinetics of a polymer. The independent variables time and temperature are separated in the two sides of the resulting equation. Thus, a physical property of the polymer, which is temperature dependent, can be matched with the theoretical calculated curve from a supposed model of transition kinetics in which only time is involved as the independent variable. By comparing different models, one may judge which model is probably more correct. The procedure of data fitting is described. As an application example, the measured viscosity data at different temperatures for the coil-globule transition of poly(N-isopropylacrylamide) in aqueous solution is tested to judge its transition mechanism. A transition mechanism involving a two-stage reversible reaction fits the experimental data in a satisfactory way. (c) 2005 Wiley Periodicals, Inc.