TAYLOR-MADE BLOCK COPOLYMERS OF POLY(ACRYLIC ACID) AS PIGMENTS SURFACE MODIFICATION AGENTS

摘要

The influence of molecular architecture and composition of block copolymers on their solid-liquid interface behaviour were investigated in details. For this purpose, the surface modification of hydrophilic titanium dioxide and hydrophobic copper phthalocyanine pigments in aqueous dispersion has been studied by a series of amphiphilic block copolymers. As pigment stabilisers, amphiphilic copolymers consisting of poly(isobornyl acrylate) (PiBA) and poly(acrylic acid) (PAA) with well-defined molecular structure, controlled molecular mass and narrow polydispersity index have been synthesised by atom transfer radical polymerisation (ATRP) by the macro-initiator strategy (to yield block copolymers). The dispersion stability, with and without the use of ultrasonic power, was studied by the electrokinetic sonic amplitude (ESA) method. Data obtained showed that the ultrasonic treatment causes a significant increase in the amount of a polymer absorbed on the particle surface, which is primarily attributed to the ultrasonicallyinduced activation of the pigment surface.