US 11,851,604 B2
Cationic nitrogen-containing heterocycles and their application in wellbore stability
Hasmukh A. Patel, Katy, TX (US); and Carl Thaemlitz, Cypress, TX (US)
Assigned to SAUDI ARABIAN OIL COMPANY, Dhahran (SA)
Filed by Saudi Arabian Oil Company, Dhahran (SA)
Filed on Jul. 26, 2022, as Appl. No. 17/873,392.
Application 17/873,392 is a division of application No. 17/004,563, filed on Aug. 27, 2020, granted, now 11,427,743.
Prior Publication US 2022/0380654 A1, Dec. 1, 2022
Int. Cl. C09K 8/12 (2006.01); C08G 73/06 (2006.01); C09K 8/528 (2006.01)
CPC C09K 8/12 (2013.01) [C08G 73/0694 (2013.01); C09K 8/528 (2013.01)] 13 Claims
 
1. A method of making a cationic polymer, comprising
introducing a substituted benzene or a substituted triazine of formula (2) to a N-containing heterocycle to obtain a reaction mixture having a molar ratio of the substituted benzene or the substituted triazine of formula (2) to the N-containing heterocycle:

OG Complex Work Unit Chemistry
where
A1, A2, A3, A4, A5, and A6 are independently C or N;
R1, R2, R3, R4, R5, and R6 are independently a bond to the N-containing heterocycle, a hydrogen radical, X, an unsubstituted alkyl, or an alkyl bearing at least one substituent X;
X is independently Cl, Br, or I; and
at least one of R1, R3, and R5 is X and the others of R1, R3, and R5 are a bond to the N-containing heterocycle; and
maintaining the reaction mixture in a solvent at a temperature from 0° C. to 50° C. for from 2 hours to 24 hours; and
wherein the cationic polymer has a weight-average molecular weight from 10 kilodaltons (kDa) to 1000 kDa;
wherein the cationic polymer comprises repeating units of formula (1):
[A-B]  (1)
where
A is the substituted benzene or a substituted triazine of formula (2); and
B is the N-containing heterocycle.