SAP’s are water absorbing crystals capable of absorbing many times their weight. SAP’s come in a variety of chemistries to suit specific applications. Absorbency can range from 20-30x its weight up to and exceeding 300x its weight. Factors that impact the absorbency include ionic concentration and pH of the fluid and specific chemistry of the SAP itself. SAP can also be differentiated by retention capability over time, under pressure, and mixture blends to maximize other key performance characteristics. Additional useful features of Zappa Stewart SAPs include: long term liquid retention, absorbency under load, and functional additive blending.