Premium
Effects of hydrophobic interactions on swelling of carboxylated core‐shell structured latex particles
Author(s) -
Nakamura H.,
Tachi K.
Publication year - 1997
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/(sici)1097-4628(19970906)65:10<1933::aid-app10>3.0.co;2-y
Subject(s) - swelling , materials science , core (optical fiber) , shell (structure) , composite material , polymer chemistry , chemical engineering , polymer science , engineering
Carboxylated core‐shell particles which contain carboxyl groups in the shell polymer swell in aqueous dispersion by electrostatic repulsion between carboxylate ions. Effects of hydrophobic interactions on the swelling of carboxylated core‐shell particles were examined by measuring their diameters as a function of various hydrophobicities of the neutralizing amine, the shell polymer, and the dispersion medium. When the dispersion is neutralized by hydrophobic amine which does not contain a hydroxyl group, the swelling is promoted for low pH and suppressed for high pH with increasing the hydrophobicity of the amine. This result suggests that the amine is concentrated near the particle surface by hydrophobic attractions. This concentrated amine promotes dissociation of carboxyl groups of the shell polymer, but combines with dissociated carboxylate ion electrostatically just like a crosslinker. As the hydrophobicity of the amine increases, the amine becomes highly concentrated, and the dissociation of the carboxyl groups and crosslinking are promoted. The swelling is suppressed when the hydrophobicity of shell polymer increases, and that is promoted when the hydrophobicity of dispersion medium increases. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65: 1933–1938, 1997