Abstract
We present the synthesis of polymer colloids with continuously
tunable anisotropy dimensions: patchiness, roughness, and
branching. Our method makes use of controlled fusion of multiple
protrusions on highly cross-linked polymer particles produced by
seeded emulsion polymerization. Carefully changing the synthesis
conditions, we can tune the number of protrusions, or branching, of
the obtained particles from spheres with one to three patches to
raspberry-like particles with multiple protrusions. In addition to that,
roughness is generated on the seed particles by adsorption of secondary
nucleated particles during synthesis. The size of the roughness relative
to the smooth patches can be continuously tuned by the initiator, surfactant, and styrene concentrations. Seed colloids chemically
different from the protrusions induce patches of different chemical nature. The underlying generality of the synthesis procedure
allows for application to a variety of seed particle sizes and materials. We demonstrate the use of differently sized polyNIPAM(poly-
N-isopropylacrylamide), as well as polystyrene and magnetite filled polyNIPAMseed particles, the latter giving rise to magnetically
anisotropic colloids. The high yield together with the uniform, anisotropic shape make them interesting candidates for use as smart
building blocks in self-assembling systems.
Original language | Undefined/Unknown |
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Pages (from-to) | 7175-7181 |
Number of pages | 7 |
Journal | Journal of Physical Chemistry. B |
Volume | 115 |
Issue number | 22 |
DOIs | |
Publication status | Published - 2011 |