title: Incorporation of gold nanoparticles within thermoresponsive microgel particles: effect of crosslinking density.
abstract: Hybrid microgel particles were prepared by one step incubation of poly(N-isopropylacrylamide)-co-poly(acrylic acid) (PNIPAM-co-PAA) and gold nanoparticles (AuNPs). PNIPAM-co-PAA microgel particles were synthesized by surfactant-free emulsion polymerization with different crosslinking densities (4.5 wt.-%, 10 wt.-%, 15 wt.-%, MBA to NIPAM) and AuNPs obtained by trisodium citrate reduction method independently. The effect of crosslinking density of synthesized microgel particles on the loadings of AuNPs was investigated. The results showed that 18 +/- 2 nm AuNPs could be well entrapped in the loosely crosslinked (4.5 wt.-%, MBA to NIPAM) PNIPAM-co-PAA microgel particles with high loadings. The final hybrid microgel particles were well characterized by transmission electron microscopy (TEM), UV-vis spectra, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and FT-IR. In particular, the PNIPAM-co-PAA/AuNPs hybrid microgel particles were thermoresponsive and completely reversible with several heating/cooling cycles. Therefore, the PNIPAM-co-PAA/AuNPs hybrid microgel particles allow for combined surface plasmon and thermal switching applications.
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, People's Republic of China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Dong
authors.forename: Ying
authors.initials: Y
authors.lastname: Ma
authors.forename: Tianyou
authors.initials: T
authors.lastname: Zhai
authors.forename: Yi
authors.initials: Y
authors.lastname: Zeng
authors.forename: Hongbing
authors.initials: H
authors.lastname: Fu
authors.forename: Jiannian
authors.initials: J
authors.lastname: Yao