Methods for upcycling crosslinked sodium polyacrylate to pressure sensitive adhesives via (a) mechanochemical chain-shortening and esterification or (b) esterifying with high conversion with a Fischer esterification process are disclosed. Also disclosed is a pressure sensitive adhesive prepared by the disclosed methods and articles comprising the pressure sensitive adhesive, including, but not limited to, pressure sensitive tape, a bandage, a label, note pads, a decal, a stamp, an envelope, a sticker, packaging, automobile trim, and a film.