Abstract:Attapulgite(ATP)was modified by four cationic surfactants with different structures,which are cetyl trimethylammonium bromide(CTAB),dodecyl dimethyl benzyl ammonium bromide(DDBAB),cetylpyridinium bromide(CPB)and didodecyldimethylammonium bromide(DDAB).The grease was prepared using modified ATP as the thickener,and its physiochemical and tribological properties were tested.The results show that the structures and properties of the cationic surfactants have an important influence on the performance of the grease.From the aspect of physicochemical properties,four kinds of greases have better thermal stability and colloidal stability and have a certain degree of corrosion,in which CTAB grease has the best comprehensive performance.From the perspective of friction and wear behavior,DDAB and CPB greases possess better friction reducing properties,because the former contains a pair of long chain alkyl which helps to combine ATP with base oil,while the latter has conjugated π bond,which can reduce the negative charge of the surface of ATP by the induction effect of the charge.This is the reason that ATP greases have the excellent tribological properties.