Polyanionic Cellulose (pac) : Petroleum drilling, especially in salt well and offshore oil drilling. In the shape of white to light yellow powder or particles, polyanionic cellulose is tasteless, nontoxic, strong in hygroscopicity, and freely soluble in cold and hot water. Polyanionic cellulose polymer has excellent heat-resistant stability, salt tolerance and strong antibacterial activity. The slurry or fluid prepared from the product has better fluid loss reducing capability, rejection capability and higher temperature tolerance. Polyanionic cellulose is widely used in petroleum drilling, especially in salt well and offshore oil drilling.