Effects of hydrophobic interaction on rheological behavior and microstructure of carboxylated core‐shell latex suspension

Abstract

ABSTRACT:We have investigated the effects of hydrophobic interactions on the rheological behavior and microstructure of suspension of carboxylated core-shell latex particles with changing hydrophobicity of shell polymer and suspending medium. The carboxylated core-shell latex particles formed lattice-like microstructures in aqueous suspension with dissociation of carboxyl groups. With increasing hydrophobicity of the shell polymer, the interparticle distance in the microstructure decreased. However, increased with increasing hydrophobicity of the suspending medium. The effect of hydrophobic interaction on was explained by the steric stabilization theory for particles with grafted polymer on the surface. As the carboxylated coreshell latex particles overlapped each other in the microstructure, an attractive force was generated between the particles in aqueous suspension. With increasing hydrophobicity of the shell, the attractive force increased, but with increasing hydrophobicity of the suspending medium, the attractive force decreased.

Preparation of core‐shell latexes for paper coatings

“…Via core-shell polymerization it is also possible to get otherwise incompatible monomers into one particle or to add functionality either into the core or into the shell. [1][2][3][4][5][6][7][8] There are many different morphologies of the core-shell structure: ideal core-shell, interface with a wavy structure, interface with a gradient of both core and shell, interface with microdomains and those with microdomains in the interface and an island structure as shell. There is a variety of analytical techniques for characterization of coreshell particle morphology including transmission electron microscopy (TEM), scanning electron microscopy (SEM), atomic force microscopy (AFM), differential scanning calorimetry (DSC), dynamic light scattering (DLS), solid-state NMR and surfactant titration.…”