Hydrated Clay for Catalyst Removal in Copper Mediated Atom Transfer Radical Polymerization

✍ Scribed by Selvaraj Munirasu; Ashwini Deshpande; Durairaj Baskaran

• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 208 KB
• Volume: 29
• Category: Article
• ISSN: 1022-1336
• DOI: 10.1002/marc.200800240

✦ Synopsis

Abstract

A simple method has been described to remove catalyst from the copper mediated atom transfer radical polymerization (ATRP) of benzyl methacrylate and methyl methacrylate in anisole at 25 °C using hydrated natural clay (sodium montmorillonite, Na‐clay). The method consists of (1) addition of hydrated clay (Cu^I^/clay ≈ 5 wt.‐%) either during or after the polymerization, (2) oxidation of catalyst complex by exposing the terminated reaction mixture in air, and (3) filtration to obtain catalyst free polymer solution. A strong coordination of CuBr‐ligand complex onto hydrated clay (10 wt.‐% < H~2~O/clay < 30 wt.‐%) upon oxidation resulted in polymers with no or insignificant residual catalyst (<1.74 ppm), as determined by UV‐vis and atomic absorption spectroscopy. The recovered clay exhibited expanded intercalary layers and absence of polymer within it.

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