The terpolymer composed of ethylene,vinyl acetate and polyether of vinyl alcohol is a new surfactant type pour point depressant (WHP) with high molecular weight.

• 由乙烯、醋酸乙烯酯和乙烯醇聚醚组成的三元共聚物（WHP）是一种新型高分子表面活性剂型原油降凝剂。