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Kinetics of high conversion polymerization of vinyl acetate. Effects of mixing and reactor type on polymer properties
Author(s) -
Baade W.,
Moritz H. U.,
Reichert K. H.
Publication year - 1982
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.1982.070270634
Subject(s) - branching (polymer chemistry) , polymerization , continuous stirred tank reactor , molar mass distribution , polymer , continuous reactor , vinyl acetate , polymer chemistry , chemical engineering , plug flow reactor model , materials science , kinetics , batch reactor , suspension polymerization , chemistry , organic chemistry , composite material , catalysis , copolymer , physics , quantum mechanics , engineering
In the present article the kinetics of polymerization of vinyl acetate in suspension up to high conversion was studied. The molecular weight distribution and the side chain branching of polyvinyl acetate produced were examined with respect to micro and macro mixing as well as to reactor type. The following results were achieved: the time–activity curves of the polymerization can be described up to high conversions considering the exponential increase in viscosity of the polymerizing system and combining the viscosity with rate constants of the polymerization. The change of volume of the polymerizing system has no significant influence on kinetics. The narrowest molecular weight distribution of the poly(vinyl acetate) produced was achieved when polymerizing in the homogeneous continuous stirred tank reactor while the broadest molecular weight distribution was observed in the segregated continuous stirred tank reactor. The batch reactor and the flow tube reactor produce polymers with molecular weight distributions lying in between. Considering the side chain branching, another order was found. The batch reactor and the tube reactor show the lowest side chain branching, the homogeneous continuous stirred tank reactor shows a larger one and the segregated continuous stirred tank reactor shows the largest. Possible reasons for the different behavior of the different reactors are discussed. The degree of segregation was determined by experiments.