Poly(N-isopropylacrylamide)-grafted silica as a support of platinum colloids: Preparation method, characterization, and catalytic properties in hydrogenation

摘要

We investigated the composition, properties, and utility of a novel hybrid material of poly(N-isopropylacrylamide)-grafted silica. The modified silica was prepared in two steps: (1) grafting silane layers of active precursors, such as initiator, transfer agent or comonomer onto the silica surface by solution deposition and (2) radical polymerization of N-isopropylacrylamide (NIPAAm) on the grafted silane layers. Thermogravimetric analysis (TGA), elemental analysis (EA), FTIR spectroscopy, and TEM were used to characterize the layer composition, structure, and chemistry, respectively. Well-dispersed platinum colloids have been prepared on the PNIPAAm-grafted silica via the reduction of PtCl62- by ethanol. The immobilized Pt colloids were found to be active and stable heterogeneous catalysts for the hydrogenation of ally alcohol in ethanol. (C) 2000 John Wiley & Sons, Inc. [References: 21]