The polymerization processes of methylene diphenyl diisocyanate (MDI) had been studied in flow atmosphere of high purity N(2) using TG-DSC-DTG techniques. The kinetic parameters of the polymerization process were calculated through the Flynn-Wall-Ozawa method and the polymerization raechanism of MDI was also studied with the Satava-Sestak and Coats-Redfern methods. The results indicated that: the process calculated could be attributed to the mechanism of random nucleation and subsequently growth, with the mechanism function being G(alpha)=[-In(1-alpha)](1/2). The activation energy and pre-exponential factor were E=58.42 kJ/mol and A=5006 min(-1), the kinetic equation may be expressed as: [-In(1-alpha)](1/2)=5006 Xexp(-58.42X1000)/8.314XT)t.The polymerization processes of methylene diphenyl diisocyanate (MDI) had been studied in flow atmosphere of high purity N(2) using TG-DSC-DTG techniques. The kinetic parameters of the polymerization process were calculated through the Flynn-Wall-Ozawa method and the polymerization raechanism of MDI was also studied with the Satava-Sestak and Coats-Redfern methods. The results indicated that: the process calculated could be attributed to the mechanism of random nucleation and subsequently growth, with the mechanism function being G(alpha)=[-In(1-alpha)](1/2). The activation energy and pre-exponential factor were E=58.42 kJ/mol and A=5006 min(-1), the kinetic equation may be expressed as: [-In(1-alpha)](1/2)=5006 Xexp(-58.42X1000)/8.314XT)t
