摘要 |
<p>Oil-soluble viscosity index-improving ethylene copolymers, such as copolymers of ethylene and propylene; and ethylene, propylene and diolefin; etc., are reacted or grafted with ethylenically unsaturated carboxylic acid moieties, preferably maleic anhydride, and reacted with polyamines having two or more primary amine groups and a carboxylic acid component, preferably alkylene polyamine and alkenyl succinic anhydride, such as polyisobutenyl succinic anhydride; or the grafted ethylene copolymer can be reacted with already formed salts, amides, imides, etc. of said polyamine and acid component, preferably imides of alkylene polyamine and alkenyl succinic anhydride. These reactions can permit the incorporation of varnish inhibition and dispersancy into the ethylene copolymer while inhibiting crosslinking with resulting viscosity increase, haze or gelling.</p> |