title: Encapsulation of polystyrene latex with temperature-responsive poly(N-isopropylacrylamide) via a self-assembling approach and the adsorption behaviors therein.
abstract: Temperature-responsive poly(N-isopropylacrylamide) (PNIPAm)-encapsulated polystyrene latex was prepared via a layer-by-layer self-assembly of cationic and anionic polyNIPAms alternately. Studies showed that the size of PNIPAm-encapsulated polystyrene particles (m-PS) increased with the encapsulation manipulation, as verified by both transmission electron microscopy and dynamic light scattering measurements. The m-PS underwent a dramatic volume decrease at the lower critical solution temperature (LCST) of PNIPAm, with the onset temperature shifting to a higher temperature range as the number of encapsulating layers increased. A qualitative study on the adsorption behavior of Ag nanoparticles revealed that while the pristine (p) Ag nanoparticles were predominantly adsorbed on the m-PS below the LCST, the hydrophobically modified one (m-Ag) was preferentially adsorbed on the same PS above the LCST, which corresponded to the hydrophilic to hydrophobic transition of the m-PS at the LCST.
authors.affiliation: School of Chemical & Biomolecular Engineering and IPST at GT, Georgia Institute of Technology, Atlanta, Georgia 30332-0620, USA.
authors.forename: Qunhui
authors.initials: Q
authors.lastname: Sun
authors.forename: Yulin
authors.initials: Y
authors.lastname: Deng
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry*; D000327:Adsorption; D007840:Latex; D008958:Models, Molecular; D049329:Nanostructures / Q000737:chemistry; D011137:Polystyrenes; D012834:Silver / Q000737:chemistry; D013816:Thermodynamics
chemical_list: D000180:Acrylic Resins; D007840:Latex; D011137:Polystyrenes; C052970:poly-N-isopropylacrylamide; D012834:Silver