Catalytic aspect of chemical modifications of polymers by transesterification: NMR study with model compounds

The catalytic activity of different compounds (dibutyl tin oxide, titanium tetrabutoxide, zirconium tetraethoxide, and para-toluenesulfonic acid) for transesterification reactions between polymers was studied. This study was carried out on three different reactions: between two model compounds (meth yl benzoate and octyl acetate), between a polymer and a model compound (eth ylene-vinyl acetate copolymer and methyl benzoate), and for crosslinking of ethylene-vinyl acetate copolymer with dimethyl terephthalate. For these th ree reactions dibutyl tin oxide presented the higher catalytic activity. (C ) 2000 John Wiley & Sons, Inc.