Description

Colloidal microgels that are able to alter their
volume and properties in response to environmental
stimuli are attractive materials for various
applications. However, current methods to prepare
microgels that possess both pH- and temperature-
sensitive properties still suffer from two major
drawbacks: 1) Limit to the use of pH-sensitive
vinylic monomer. Thus, many pH-sensitive polymers
like bio- and synthetic polymers cannot be used. 2)
Phase transition temperature of the polymer is
influenced by protonation degree of
the pH-sensitive polymer. In this book, a novel
method to prepare smart microgels that consist of
well-defined temperature-sensitive cores
with pH-sensitive shells is described in details.
The microgels are synthesized directly from aqueous
graft copolymerization of N-isopropylacrylamide or N-
vinylcaprolactam with a crosslinker, from water-
soluble polymer of poly(ethyleneimine) or chitosan.
The well-defined core-shell nanostructure exhibits
tuneable responses to pH, temperature and
electrolyte changes. Thus, this new type of smart
materials should be extremely useful in drug
delivery, biosensing, separation technology, etc.