10.1021/acs.macromol.9b00841.s001
Zhi Chen
Zhi
Chen
Yongliang Zhao
Yongliang
Zhao
Xiaomin Zhu
Xiaomin
Zhu
Martin Möller
Martin
Möller
Formation of Monodisperse Polymer@SiO<sub>2</sub> Core–Shell
Nanoparticles via Polymerization in Emulsions Stabilized by Amphiphilic
Silica Precursor Polymers: HLB Dictates the Reaction Mechanism and
Particle Size
American Chemical Society
2019
emulsion
Particle Size Heterophase polymerization
formation
Amphiphilic Silica Precursor Polymers
HLB
amphiphilic silica precursor polymers
dispersion
droplets
Polymerization
PEGylation degree
2019-07-18 16:27:27
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Formation_of_Monodisperse_Polymer_SiO_sub_2_sub_Core_Shell_Nanoparticles_via_Polymerization_in_Emulsions_Stabilized_by_Amphiphilic_Silica_Precursor_Polymers_HLB_Dictates_the_Reaction_Mechanism_and_Particle_Size/8953583
Heterophase polymerization is the
main tool to prepare polymer
dispersions. In this work, we report on a new type of heterophase
polymerization that allows synthesizing in one step monodisperse polymer@SiO<sub>2</sub> core–shell particles in a wide size range from tens
to hundreds of nanometers. The strategy utilizes amphiphilic silica
precursor polymers, namely, PEGylated polyethoxysiloxanes, which can
reduce the interfacial tension between oil and water close to zero.
An oil phase containing such a kind of surfactants can be emulsified
in water spontaneously or just under low-energy stirring. Polymerization
of styrene in the resulting emulsions using an oil-soluble initiator
leads to the formation of monodisperse polystyrene@SiO<sub>2</sub> particles, whose size can be precisely adjusted by the PEGylation
degree of precursor molecules and can reach as small as 30 nm. It
is demonstrated that the PEGylation degree, that is, the HLB, also
dictates the reaction mechanism that varies from suspension polymerization
with breakup of monomer droplets and miniemulsion polymerization to
microemulsion polymerization leading to exact “copying”
of initial emulsion droplets. This technique paves a new avenue for
simple, controllable, and environmentally friendly production of dispersions
of composite polymer particles.