Use of Sulfobetaine-Based Block Copolymer as Stabilizer in Silver Nanoparticle Production and Catalytic Activity Studies

Abstract

A zwitterionic sulfobetaine-based diblock copolymer was successfully synthesized and used in the preparation and stabilization of Ag nanoparticles (AgNPs). For the related block copolymer, a precursor AB type diblock copolymer was synthesized via atom transfer radical polymerization by using a MPEG-based ATRP macroinitiator and 2-(N-dimethylamino)ethyl methacrylate (DMA) comonomer. Tertiary amine residues of PDMA blocks in poly(ethylene glycol) methyl ether-b-poly[2-(N-diethylamino)ethyl methacrylate] (MPEG-b-PDMA) precursor was then converted to polybetaine structures by reacting with 1,3-propanesultone to obtain poly(ethylene glycol) methyl ether-b-poly[3-dimethyl(methacryloyloxyethyl) ammonium propane sulfonate] (MPEG-b-PβDMA) derivative. The resulting block copolymer was successfully used as stabilizer in the chemical and sonochemical synthesis of spherical AgNPs with a diameter in the range of 7.9-9.3 nm. The average diameter of AgNPs synthesized by sonochemical method was smaller than those synthesized by chemical method. The MPEG-b-PβDMA diblock copolymer was determined to be a good stabilizer for AgNPs. The AgNPs dispersion was stable for more than 5 months without any flocculation at room temperature. The catalytic activity of polymer-AgNP dispersion was also investigated in the reduction of p-nitrophenol to p-aminophenol and was found to be quite effective.

Production of NiO, NiO/Ag, NiO/Au, and NiO/Pt hollow spheres by using block copolymer stabilized microspheres as a template

“…The styrene monomer was purified by passing through basic alumina (SI‐AL) column. Small diameter Au, Ag, and Pt nanoparticles were produced and characterized as reported in our previous study 37,38 …”

“…NiSO 4 solution (0.20 M, 10.0 ml) was then added and stirred for 24 h. Then, 3.0 g of urea was dissolved in water (10.0 ml) and added to the reaction medium and stirred at 80 °C for 48 h. At the end of the reaction, the pH of the medium was around 12 due to urea decomposition and ammonia formation. The production of NiO/metal NPs hollow spheres was accomplished by adding 1.0 ml of Au (4.50 ± 1.1 nm), Ag (7.95 ± 1.4 nm), and Pt (3.80 ± 0.6 nm) nanoparticle dispersions, which we previously produced, together with the NiSO 4 solution 37,38 . The product was centrifuged three times at 5000 rpm and washed 3 times with distilled water.…”

Nanofabrication of hybrid nanomaterials: Macroscopically aligned nanoparticles pattern via directed self‐assembly of block copolymers

“…It was observed that particle size had an important effect on catalytic activity of AgNPs. The catalytic activity decreased with an increase on AgNPs diameter but increased with nanometal concentration 102 …”

“…The catalytic activity decreased with an increase on AgNPs diameter but increased with nanometal concentration. 102…”