From Figure , it is very clear that the enzymatic digestibility of the acetylated papers is significantly impeded by the presence of CTA, with the 6-acetylated only (no CTA) samples still allowing for considerable weight-loss during the experimental time frame. It is important to note that the enzyme cocktail that is used does not contain esterases to catalyse deacetylation (potentially increasing local swelling), which has been proposed as a key initial step in biodegradation of high DS acetate . Thus, the weight loss is solely based on the action of polysaccharide-fragmenting enzymes. As such, it was surprising to note that the DS of acetylation of the residual paper did not change after 40 % enzymatic weight loss. This indicates that at the lower DS values, in the absence of a CTA fibril coating, the enzymes either fragment both the partially acetylated polymers, or the low DS surface chains become soluble in the media after enzymatic attack. This is not totally unexpected as low DS cellulose acetate (DS ~ 0.5-1) is known to be water soluble .