<p>Food packaging films often contain both polyethylene (PE) and poly(vinyl alcohol-co-ethylene) (EVOH) layers. When such films are melted, the two polymers segregate and the resultant melt has poor properties for re-use. Using acid catalysts, EVOH can be dehydrated, and subsequent hydrogenation of the resulting unsaturated bonds should improve compatibility of the two polymers, facilitating recycling. Here we present results of a TGA investigation into the influence of catalyst acid site density and pore size on the catalytic performance of different zeolites for the dehydration of molten EVOH. Catalysts were characterized using isopropyl amine temperature-programmed reaction (IPA-TPRx) and Fourier transform infrared (FTIR) measurements of adsorbed 2,6-di-tert-butylpyridine, which quantify total Bronsted acid sites and external acid sites, respectively. Zeolite frameworks MFI, BEA, and FAU, with varying Si:Al ratios, were used along with an amorphous silica-alumina catalyst to gain insight into the effects of pore size and acid site density. Reaction rates at early reaction times and low fractional conversions are used to measure effects of internal and external mass transfer. The observed reaction rates are strongly affected by mass transfer limitations as expected. Results suggest polymer chain ends are able to penetrate into pores in all the zeolites used. A core-shell catalyst was used to enable quantification of external versus internal turnover frequencies.</p>