	US 12,134,732 B2
	Fluid loss control additive
Peter Boul, Houston, TX (US); and Kenneth Dejuan Johnson, Houston, TX (US)
Assigned to Saudi Arabian Oil Company, Dhahran (SA)
Filed by Saudi Arabian Oil Company, Dhahran (SA)
Filed on Dec. 8, 2021, as Appl. No. 17/643,252.
Prior Publication US 2023/0174844 A1, Jun. 8, 2023
Int. Cl. C09K 8/487 (2006.01); C04B 14/30 (2006.01); C04B 24/00 (2006.01); C04B 24/16 (2006.01); C04B 24/26 (2006.01); C04B 24/34 (2006.01); C04B 28/08 (2006.01); C09K 8/514 (2006.01); C04B 103/00 (2006.01); C04B 103/32 (2006.01); C04B 103/46 (2006.01); C04B 103/50 (2006.01)

CPC C09K 8/487 (2013.01) [C04B 14/30 (2013.01); C04B 24/003 (2013.01); C04B 24/163 (2013.01); C04B 24/2647 (2013.01); C04B 24/34 (2013.01); C04B 28/08 (2013.01); C09K 8/514 (2013.01); C04B 2103/0035 (2013.01); C04B 2103/0059 (2013.01); C04B 2103/32 (2013.01); C04B 2103/46 (2013.01); C04B 2103/50 (2013.01)]

28 Claims

1. A fluid loss control additive comprising:

a copolymer comprising 2-acrylamido-2-methylpropane sulfonic acid monomer units and acryloylmorpholine monomer units; and

a graft copolymer comprising a humate and, grafted onto the humate, a side-chain polymer comprising:

acrylamide monomer units;

acryloylmorpholine monomer units;

acrylic acid monomer units; and

2-acrylamido-2-methylpropane sulfonic acid monomer units;

wherein:

the acrylamide monomer units comprise about 10% to about 40% of a total number of monomer units of the side-chain polymer;

the acryloylmorpholine monomer units comprise about 5% to about 35% of a total number of monomer units of the side-chain polymer;

the acrylic acid monomer units comprise about 10% to about 40% of a total number of monomer units of the side-chain polymer; and

the 2-acrylamido-2-methylpropane sulfonic acid monomer units comprise about 20% to about 75% of a total number of monomer units of the side-chain polymer.