The current invention includes a composition having stability additives of selected inorganic salts and/or organic incorporated into an aldehyde-functionalized polymer product. The stability additive can be post added to the finished polymer product, added to the reaction vessel prior to inducing functionalization of the non-functionalized polymer, or added at any stage during the functionalization reaction. Methods for forming the composition and using the composition to produce a cellulosic fiber-based medium are also disclosed.