n - substituted acrylamidines having the general formula : ## str1 ## in which r 1 is an isopropyl group , r 2 and r 3 each is hydrogen , ethyl , propyl , butyl , pentyl , octyl , or octadecyl . the acrylamidine is copolymerized with at least one ester of acrylic and / or methacrylic acid esters , and the copolymer has use as an oil additive and for the manufacture of molded articles , paints and adhesives .