Vol 61 No 3 (2016): Journal of the Chilean Chemical Society
Original Research Papers


Zaffar Iqbal
Department of Chemistry, Quaid-I-Azam University
Luqman Ali Shah
Department of Chemistry, Quaid-I-Azam University National Centre of Excellence in Physical Chemistry, University of Peshawar
Murtaza Sayed
Department of Chemistry, COMSATS Institute of Information technology
Abdul Haleem
Department of Chemistry, Quaid-I-Azam University
Mohammad Siddiq
Department of Chemistry, Quaid-I-Azam University
Published September 10, 2016
  • Free radical emulsion polymerization,
  • In-situ reduction method,
  • Hybrid microgels,
  • Surface plasmon resonance,
  • Catalytic activity


Copolymer microgel composed of N-isopropyl acrylamide and methacrylic acid, poly(NIPAM-MAA), was synthesized by free radical emulsion polymerization using N,N-(1,2-dihydroxyethylene) bisacrylamide as cross-linking agent. The hybrid microgels poly(NIPAM-MAA)-Au and poly(NIPAM-MAA)-Ag, were synthesized by in-situ reduction of metal ions using sodium borohydride (NaBH4) as reducing agent. The temperature and pH sensitivity of pure and hybrid microgels were studied by dynamic light scattering (DLS) and UV-Visible spectroscopy. The existence of gold and silver nanoparticles inside the microgel network was confirmed by transmission electron microscopy (TEM). Poly(NIPAM-MAA)-Au and poly(NIPAM-MAA)-Ag hybrid microgels were tested for the comparative catalytic activity towards the reduction of 4-nitrophenol to 4-aminophenol. The apparent rate constant (kapp) for poly(NIPAM-MAA)-Au was found superior than poly(NIPAM-MAA)-Ag. 



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