聚陰離子纖維素（PAC）

　聚陰離子纖維素是一種高品質水溶性纖維素衍生物，其商業產品分為兩種：PAC-L和PAC-H，皆可有效的提高水基鉆井液，其中包括淡水、海水和飽和鹽水鉆井液的年度并降低濾失量，但PAC-L沒有PAC-H那么強的增稠效應，PAC的一般加量為0.2%～0.6%。

PAC PAC-polyanionic cellulosic polymer is a high quality water soluble cellulose derivative.The commercial products of PAC can be divided into two categories，PAC-L and PAC-H. Both of them can effectively enhance viscosity and reduce fluid loss in water base drilling fluid inclusive saturated salt water drilling fluid system provided。 PAC-L has lesser viscosifying effect than PAC-H. The common dosage of PAC is in the range of 0.2%～0.6%.