In the five kinds N,N-dialkylacylamides, it is difficult for N,N-diethylacylamides to perform effectively in oil collecting because the maximum of film pressure caused by N,N-dialkylacylamides is just about 38 mN/m.

• 五种酰胺中因N,N-二乙基酰胺所能产生的最高膜压仅有38mN/m，很难起到良好的集油作用；