Modified Ozawa Method

5 General Description of Kinetics of Resin Curing Under Isothermal Conditions 

Spherical, diffusion Athermal increasing with time 3/2 

Truncated sphere Athermal increasing with time 2-3 

---

DMA, the kinetic parameters of the glass transition can be determined by multicurves methods such as the Ozawa method (see Chapter 4). While only one heating rate is available here, the modified Coats-Redfern method is used [13, 14] as demonstrated in the following. Integration of Eq. (2.12) leads to ... 

In this study, the modified Kissinger method was applied to polypropylene crystallization in the presence of inorganic additives. Minerals such as talc in fine powder format could influence the crystallization behavior of polypropylene as reported [19,20]. With the use of the modified Kissinger method, chain mobility due to the additive effect in crystallization could be revealed. Avrami and Ozawa methods were also applied to analyze the crystallization kinetics and used in conjunction with the apparent energy to better characterize the crystallization behavior. This method could facilitate resin and additive selection and provide simulation of the crystallization behavior of polypropylene in melt processing. 

These observations indicated that with the use of apparent energy Irom the modified Kissinger method, a growth-related energy could be generated. This, in conjunction with the Avrami and Ozawa methods, provided more complete understanding for crystallization kinetics. The effect of talc may be compared with that of other additives by using this approach. 

Transformation kinetics according to Ozawa Ozawa (2) proposed a method to predict crystallization of polymers under constant cooling or heating rate by modifying the Avrami equation ... 

The nonisothermal crystallization kinetics of polymers can start with isothermal crystallization, and be corrected considering the characteristics of nonisothermal crystallization. The common DSC methods include Jeziomy, Ozawa, and MoZhishen methods. The nonisothermal crystallization kinetics of pure PP and 5% whisker-filled PP are compared using the Jeziorny modifying method of the Avrami equation. 

The kinetics of non-isothermal crystallization using differential scanning calorimeUy (DSC) has been a known approach to study the crystallization behavior of polymers. The analysis was commonly performed through the use of modified Avrami [1 ], Ozawa [5] and other methods [6-7]. Kissinger method [8] was often used to obtain the activation energy of crystallization. These methods have been helpful to differentiate the crystallization behavior between materials. 

---