The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 15, 1989
Filed:
Feb. 22, 1988
Derek Redmore, St. Louis, MO (US);
Balram Dhawan, St. Louis, MO (US);
John L Przybylinski, St. Louis, MO (US);
Petrolite Corporation, St. Louis, MO (US);
Abstract
A method for inhibition of scale formation using a composition comprising an N-phosphonomethylated amino-2-hydroxypropylene polymer having a molecular weight of between about 300 and about 5000 and having the structural formula ##STR1## wherein (i) R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are independently selected from the group consisting of hydrogen, phosphonomethyl radical corresponding to the formula --CH.sub.2 PO(OH).sub.2, and water treating acceptable salts of such phosphonomethyl radical, with the proviso that the percentage of R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 being hydrogen does not exceed about 30; (ii) R is a divalent radical selected from the group consisting of (a) unsubstituted alkylene groups having at least about 2 and at most about 12 carbon atoms, (b) substituted alkylene groups having at least about 2 and at most about 12 carbon atoms wherein at least one hydrogen of the alkylene group is substituted with a radical selected from the group consisting of methyl, ethyl, propyl, butyl, methyl ammonium, ethyl ammonium and ammonium groups, and the other hydrogens of the substituted alkylene group are unsubstituted, (c) cycloalkylene groups having at least 3 and at most about 12 carbon atoms, and (d) --R'--N--R'-- wherein R.sub.7 is defined as R.sub.1, R.sub.2 R.sub.3, R.sub.4, R.sub.5 and R.sub.6 above, with the proviso that the percentage of R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6 and R.sub.7 being hydrogen not exceed about 30, and R' and R' are independently selected from the group consisting of such unsubstituted alkylene groups, and such cycoalkylene groups; and (iii) n is from about 1 to about 25 is disclosed.