Preparation of uniform monomer droplets using packed column and continuous polymerization in tube reactor.

A two-step continuous emulsification and polymerization process was developed in which monomer droplets having narrow size distribution were prepared and polymerized while retaining their monodispersity. In the emulsification step, a column packed with glass beads, of diameters ranging from 70microm to 1mm, was used to prepare a monomer O/W emulsion. Monomer droplets were dispersed with an aqueous solution of poly(vinyl alcohol) (PVA). The droplet size and -distribution was studied with respect to the effects of diameter of glass beads, concentration of PVA in water phase, degree of polymerization of PVA, ratio of mass flow of water phase to that of oil phase, linear velocity of water phase and viscosity of water phase and oil phase. Droplet size was found to be strongly dependent on the diameter of the packed glass beads, while the droplet size distribution was affected by the viscosities of the continuous and dispersed phases. Increasing the viscosity of the dispersed phase by addition of poly(styrene) to the monomer mixture resulted in a narrow size distribution of glycidyl methacrylate-ethylene glycol dimethacrylate droplets. Furthermore, these initiator-containing monomer droplets were polymerized by heating in a tubular reactor, from which polymer particles with a narrow size distribution could be synthesized.

[1]  Gary Edward Mueller,et al.  Prediction of Radial Porosity Distributions in Randomly Packed Fixed Beds of Uniformly Sized Spheres in Cylindrical Containers , 1991 .

[2]  H. Kawaguchi,et al.  Functional polymer microspheres , 2000 .

[3]  P. Fongarland,et al.  CFD simulations of two stirred tank reactors with stationary catalytic basket , 2006 .

[4]  T. Tadros.  Emulsion Science and Technology , 2009 .

[5]  Sanjeev Kumar,et al.  A new model for coalescence efficiency of drops in stirred dispersions , 1993 .

[6]  I.P.T. Moore,et al.  Velocity distributions in a stirred tank containing a yield stress fluid , 1995 .

[7]  M. Shimizu,et al.  Particle control of emulsion by membrane emulsification and its applications. , 2000, Advanced drug delivery reviews.

[8]  B. Brooks,et al.  Drop mixing in suspension polymerisation , 2002 .

[9]  Sugiura,et al.  Preparation of Monodispersed Solid Lipid Microspheres Using a Microchannel Emulsification Technique. , 2000, Journal of colloid and interface science.

[10]  H. S. Fogler,et al.  Elements of Chemical Reaction Engineering , 1986 .

[11]  H. Peerhossaini,et al.  Droplets formation in turbulent mixing of two immiscible fluids in a new type of static mixer , 2003 .

[12]  Goran T Vladisavljević,et al.  Recent developments in manufacturing emulsions and particulate products using membranes. , 2005, Advances in colloid and interface science.

[13]  H. Fessi,et al.  The membrane emulsification process: a review , 2004 .

[14]  Minoru Seki,et al.  Continuous and size-dependent sorting of emulsion droplets using hydrodynamics in pinched microchannels. , 2008, Langmuir : the ACS journal of surfaces and colloids.

[15]  Erich J. Windhab,et al.  Drop formation in a co-flowing ambient fluid , 2004 .

[16]  R. Arshady,et al.  Suspension, emulsion, and dispersion polymerization: A methodological survey , 1992 .

[17]  Rajamani Krishna,et al.  Counter-current operation of structured catalytically packed distillation columns: pressure drop, holdup and mixing , 1999 .

[18]  G. Vladisavljević,et al.  Influence of process parameters on droplet size distribution in SPG membrane emulsification and stability of prepared emulsion droplets , 2003 .

[19]  Rodrigo J. G. Lopes,et al.  CFD modelling of multiphase flow distribution in trickle beds , 2009 .

[20]  X. Zhu,et al.  Polymer microspheres for controlled drug release. , 2004, International journal of pharmaceutics.

[21]  J. Aubin,et al.  Modeling turbulent flow in stirred tanks with CFD: the influence of the modeling approach, turbulence model and numerical scheme , 2004 .

[22]  B. Vincent,et al.  Suspension polymerisation to form polymer beads , 2000 .

[23]  G. Guiochon,et al.  Comparison between the efficiencies of columns packed with fully and partially porous C18-bonded silica materials. , 2007, Journal of chromatography. A.

[24]  T. Gu,et al.  Synthesis of macroporous poly(glycidyl methacrylate) microspheres by surfactant reverse micelles swelling method , 2007 .

[25]  A new technology for producing mono-disperse macroemulsions , 2007 .

[26]  V. E. Sater,et al.  Two-Phase Flow in Packed Beds. Evaluation of Axial Dispersion and Holdup by Moment Analysis , 1966 .