Through investigation of water clarifying mechanism of demulsifier during demulsifying period , using the theory of relationship between structure and performance of surfactant , combining with the composition character of crude oil , the molecular structure design and synthesis of demulsifier were conducted 通过探讨破乳剂在破乳过程中的清水机理,运用表面活性剂结构与性能关系理论,结合原油的组成特点,进行了破乳剂分子的结构设计与合成。