Superabsorbent polymer is primarily used to absorb bodily wastes and liquids. One area of aspartic acid market growth is biodegradable superabsorbent polymers (SAP). The internal pads are composed of pads containing wood pulp and a superabsorbent polymer (SAP). Soy protein/poly(acrylic acid) superabsorbent polymers with good mechanical strength have been prepared. The acrylates are used to make superabsorbent polymers which are used in diapers. The introduction and popularity of these toys has followed the development of superabsorbent polymers. Rely was a brand of superabsorbent tampons made by Procter & Gamble starting in 1975.