abstract |
An additive composition prepared by the steps comprising: n (A) reacting a styrene-ethylene butylene-styrene block copolymer, having a styrene-ethylene-butylene-styrene molecular weight ratios, respectively, of 1:6:1 to 1:3:1 characterized in that unsaturation in the styrene blocks is equal to or greater than 50 percent and the ethylene butylene block is hydrogenated leaving no more than 10 percent unsaturation, with at least one olefinic carboxylic acid acylating agent to form one or more acylating reaction intermediates characterized by having a carboxylic acid acylating function within their structure, and n (B) reacting said reaction intermediate in (A) with an amino-aromatic polyamine compound and a lubricating oil composition containing same are provided. |