Premium
Online monitoring of drop/particle size and size distribution in liquid–liquid dispersions and suspension polymerizations by optical reflectance measurements
Author(s) -
Xie Guiming,
Pan Pengju,
Bao Yongzhong
Publication year - 2016
Publication title -
journal of applied polymer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.575
H-Index - 166
eISSN - 1097-4628
pISSN - 0021-8995
DOI - 10.1002/app.43632
Subject(s) - materials science , methyl methacrylate , drop (telecommunication) , particle size , suspension (topology) , suspension polymerization , particle size distribution , chemical engineering , drop impact , particle (ecology) , polymer chemistry , dispersant , polymerization , composite material , dispersion (optics) , polymer , optics , telecommunications , oceanography , physics , mathematics , homotopy , computer science , wetting , pure mathematics , engineering , geology
Evolutions of drop/particle size and size distribution in liquid–liquid dispersions and suspension polymerizations of methyl methacrylate (MMA) were monitored by using an online optical reflectance measurement (ORM), and effects of operating parameters such as the agitation rate, concentration of poly(vinyl alcohol) (PVA) dispersant, and initial concentration of poly(methyl methacrylate) (PMMA) in MMA monomer on the Sauter mean diameter ( d 32 ) and size distribution of drop/particle were investigated. According to the variations of d 32 of drops/particles with time, four characteristic particle formation stages can be identified for suspension polymerization process. The factors that lead to increase the rate of drop break up, such as increasing of concentration of PVA and decreasing of viscosity of dispersed phase, would postpone the particle growth stage. The d 32 and size distribution breadth of drops/particles were significant increased when the liquid–liquid dispersions or suspension polymerizations were conducted at low PVA concentrations or MMA/PMMA solutions with high PMMA contents were used as the dispersed phase, in consistent with the scanning electron micrograph observation on final PMMA particles. It is clear that ORM can be effectively applied in online monitoring of size and size distribution of drops/particles in the liquid–liquid dispersions and suspension polymerizations. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133 , 43632.