Relative permeability modifiers (abbr. RPM) is a kind of selective water plugging agent, namely it only decreases the permeability of water phase, causes little or even no impact on oil phase.

• 相渗透率改善剂（RPM，Relative Permeability Modifiers），从性能上说属于一种选择性堵剂，即只大幅降低地层水相渗透率，而对油相渗透率降低很少甚至不降低的一种物质。