In order to optimize reactive processing conditions and synthesize polymer materials according to requirements a kinetic model of free radical polymerization of n-butylmethacrylate(n-BMA) in counter-rotating twin screw extruders was constructed mainly on the basis of the entanglement theory

and then the numerical calculation expressions of the monomer concentration

the monomer conversion

the average molecular weight and the apparent viscosity were deduced.Consequently

the free radical polymerization process of n-BMA in counterrotating twin screw extruders was numerically simulated by means of the finite volume method and an uncoupled semi-implicit iterative algorithm

and then the evolution characteristics and the influencing factors of different variables like monomer conversion

average molecular weight and fluid viscosity were discussed in detail.A comparison of the monomer conversion as well as the weight-average molecular weight between the simulated results and the experimental results shows a nearly good agreement

which indicates that the constructed model is reasonable.