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ISSN print edition: 0366-6352
ISSN electronic edition: 1336-9075
Registr. No.: MK SR 9/7
Published monthly
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Emulsion copolymerization of acrylonitrile and butyl acrylate. 3. Effect of the radical scavenger on the kinetics and polymerization behavior
I. Capek and J. Bartoň
Polymer Institute, Centre for Chemical Research,
Slovak Academy of Sciences, CS-842 36 Bratislava
Abstract: A study of the emulsion copolymerization of acrylonitrile and butyl acrylate
under batch conditions in the presence of p-benzoquinone is presented.
Statistical copolymers are synthesized by the emulsion polymerization conduc
ted to both low and high conversion using the anionic emulsifier.
It has been found that the copolymer formed at low conversion is enriched
with acrylonitrile structural units both in the presence and in the absence of
p-benzoquinone. Addition of a small amount of a radical scavenger significant
ly decreases the rate of polymerization and slightly decreases the size of
polymer particles in the range of low surfactant concentration.
It is assumed that the initiation of the emulsion copolymerization is
a two-step process. It starts in the aqueous phase by the primary radicals
derived from the water-soluble initiator which add water-soluble monomer.
These reactions lead to the formation of water-soluble or insoluble macroradi-
cals which cause at low conversion the drift in copolymer composition. The
second step occurs in micelles by radicals absorbed on the surface of micelles. It
is expected that the polymer particles generated by homogeneous nucleation
contribute to both the polymerization rate and copolymer composition.
Full paper in Portable Document Format: 401a45.pdf
Chemical Papers 40 (1) 45–60 (1986)
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