Simulation of Particle Growth in the Dispersion Polymerization of Styrene: The Termination Rate Constant in Particles

Abstract

A model is proposed for simulating the particle growth in the dispersion polymerization of styrene in ethanol. The model is based on the following assumptions: (i) the termination reaction in an ethanol‐phase and the chain‐transfer reactions in the ethanol‐phase and particles can be neglected, (ii) the mean volume of the radicals captured by particles is approximately equivalent to that of monomeric radicals, and (iii) the termination rate constant in particles is βgel times that of the ethanol‐phase. The experimental results of the conversion, the particle diameter and the particle number measured at the reaction time of 2 h were used to determine the initial conditions. When the termination rate constant in particles was taken to be about 1/130 of that of the ethanol phase, the calculation results of the conversion and the particle diameter were in good agreement with the experimental data.

Monte Carlo simulation of the dispersion polymerization of styrene

“…The simulations were performed according to the experimental conditions and recipes of Yasuda et al, 9,12 where the experiments were performed in a glass batch reactor equipped with a motor-driven stirrer with agitation at 30 rpm at 70 C. The recipes of the reaction mixtures are presented in Table 2. The experimental results of these papers were used for investigating the accuracy of our simulation.…”

“…A mechanism has been proposed based on the literature 9,11,12,16,17 to model the dispersion polymerization of styrene stabilized by polyvinylpyrrolidone in ethanol, which takes into account the reactions of styrene, 2,2 0 -azobisisobutyronitrile (AIBN) and PVP in the two phases involved namely the continuous and particles. The mechanism contains een reactions as follows:…”

“…8,9 Lu et al 10 obtained a thermodynamic model for the monomer partitioning in dispersion polymerization of styrene in ethanol. Dispersion polymerization can be divided into two main stages of particle formation and growth.…”

“…Dispersion polymerization can be divided into two main stages of particle formation and growth. Yasuda et al 9,12 concluded that the aggregation of particles due to the shear stress of the uid plays an important role in the particle formation stage. In the second stage, particles grow by absorbing polymer and monomer from the media followed by polymerization within the particles.…”

Synthesis of Amphiphilic Polymer Particles by Seed Polymerization and Their Application for Lipase Immobilization

“…[18] A clean and dry 300-mL separable flask was charged with 72.4 g of ethanol, 1.80 g of PVP, and 0.57 g of 1-hexadecanol, and covered with a 4-necked separ-able cover attached with a Dimroth condenser. The flask was heated to 70 8C with mild shaking for 20 min.…”