Kinetic model of the photoinitiated polymerization and its comparison with experimental data

Kinetic model of the photoinitiated polymerization and its comparison with experimental data 

The proposed microheterogeneous model (see equation 5.1) for thermal polymerization needs modification, It is necessary to take into account the presence of a light gradient in the layer of the photopolymerization composition, gradients in the concentrations of the photoinitiator of the oligomer and the depth of the photopolymerization. That is why in this variant of the photoinitiated polymerization equation (5.1) should be written as a partial derivative [8]  

However, as a rule, the experimentally measured parameters of the photoinitiated polymerization are not the differential rate of the proce.ss dp/di, or relative depth of the polymerization P, but their integral, that is, the average of the layer analogs. They are determined by the expression  

Using equations (5.39) and (5.43) in the integral conversion (see equation 5.76), and taking into account the theorem about the mean, the expression for the polyfunctional (meth)acrylates will be [8-10] 

Indirect comparison of experimental data with general kinetic model (see equations (5.77)- 5.79)) is complicated. Therefore, we consider two approximations, the first is based on the assumption that c=co v,=constant, which can be considered as a model of the initial stage of the process. Using condition r 1 in equations (5.77)-(5.79) we obtain  

---