Copolymerization of 1,2 bis(2-methylpropenoyloxy)ethane and divinylbenzenein aqueous suspension. Part I: control of the diameters of the beads of 1,2 bis(2-methylpropenoyloxy)ethane-divinylbenzene copolymer

The aim of the current paper is to study the influence of the interfacial t ension (sigma) and viscosity on the droplets dispersion of 1,2 bis(2-methyl propenoyloxy)ethane (EGDMA) and divinylbenzene (DVB). This dispersion is ch aracterized by the distribution of poly(EGDMA-coDVB) polymer spheres. We ex perimentally observed that this distribution is polymodal and that the expe rimental maximum diameter (d(max))(obs) is proportional to (sigma/rho(c))(0 .59) (rho(c) is the continuous phase density). This relation is valid when (d(max))(obs) much greater than eta, the Kolmogoroff turbulence microscale (which is related to the dissipated power by mass unit and the kinematic vi scosity (nu(c)) of the continuous phase). When (d(max))(obs) much less than eta, the experimental maximum diameter is not proportional to (nu(c)sigma/ rho(c))(1/3) ,but it verifies the theory of Taylor's viscous shear abrasion where the maximum diameter is proportional to sigma/[mu(c),(19p + 16)/(16p + 16)] (p = mu(d)/mu(c), mu(d) and mu(c), are the dynamic viscosity of the dispersed and continuous phase, respectively). (C) 1999 Elsevier Science L td. All rights reserved.