Nitrogen-containing esters and lubricants containing them

摘要

A nitrogen-containing ester of a carboxy-containing interpolymer which is derived from at least two monomers, one of said monomers being a low molecular weight aliphatic olefin or styrene and the other of said monomers being an alpha, beta- unsaturated aliphatic acid, anhydride or ester thereof, is characterized by the presence within its polymeric structure of at least one of each of the following groups which are derived from the carboxy groups of said interpolymer: (A) a carboxylic ester group, said carboxylic ester group having at least eight aliphatic carbon atoms in the ester radical, and (B) a carbonyl-polyamino group derived from a polyamino compound having one primary or secondary amino group and at least one monofunctional amino group, wherein the molar ratio of carboxy groups of said interpolymer esterified to provide (A) to carboxy groups of said interpolymer neutralized to provide (B) is in the range of about 85:15 to about 99:1. The product is useful as a pour point depressant in lubricating oils.