Alkenylamino-methylene-phosphonic acids and their copolymers prepn. - useful as complexing agents and as scale inhibitors in crude oil recovery

摘要

Alkenylaminomethylene phosphoric acids of formula (I) are claimed. R1 = H, 4-10C alkyl, phenyl, naphthyl, methylphenyl, hydroxyphenyl, methoxyphenyl, methylnapththyl, hydroxynaphthyl or methoxynaphthyl, esp. phenyl; R2 = H; R3, R4, R6 = H or methyl, R5 = H, 1-4C alkyl or phenyl, and M = H or Na(+), K(+) and NH4(+). Also claimed are: (i) prepn. of (I) by reacting a cpd. of formula (II) with an aldehyde of formula R1-CHO, and treating the prod. obtd. of formula (III) with an excess of phosphoric acid. (ii) copolymers comprising 0.1-99.9(1-50) wt.% of one or more monomers of formula (I), where r2 = H or CH2PO3M2, and 99.9-0.1 (99-50) wt.% of one or more monomers of formula R1@R2'C=CR3'X (IV) R1' = H or COOM; R2' = H, phenyl, or COOM; R3' = H, methyl, COOM or CH2COOM; X = COOM; R2' and R3' together = 4C alkyl; R1' and X together = cpd. of formula (V). F3' and X together = a cpd. of formula (VI) (iii) prepn. of the copolymers by polymerising (I) with (II), pref. in the presence of Na2SO4.