Acrylic dispersants with fused aromatic imide anchor groups

A polymeric dispersant comprising an olefinic backbone derived from polymerizing alpha-beta unsaturated olefinic monomers, wherein (i) at least 80 wt. % of the backbone repeat units are derived from polymerizing monomers which have the alpha-beta-olefin portion represented by (meth)acrylic acid, CH═C(G)-C(═O)—Z—, CH═C(G)

• wherein G is selected from the group consisting of H and CH3;
• and Z is a nitrogen or oxygen linking atom;
• ii) at least one of the monomers used to form the backbone is functionalized prior to or subsequent to polymerization with at least one imide group wherein the carbonyl groups of the imide are chemically bonded directly to carbon atoms of a fused aromatic ring;
• iii) wherein said dispersant has a number average molecular weight from about 1000 to about 100,000 g/mole;
• and iv) wherein said dispersant has at least one polymeric backbone block characterized as being an anchoring block that has chemically attached thereto said imide group and said polymeric backbone has also attached thereto at least one polymeric segment of 300 to 5000 g/mole molecular weight characterized as a solvent solubilizing polymeric segment;
• wherein the dispersant has a structure according to formula 1 below
• wherein each G independently is a CH3 or H group or mixtures thereof
• A is a moiety comprising a fused aromatic imide group,
• B is a pendant moiety off a —CH2—C(G)- derived from polymerizing ethylenically unsaturated monomers of which at least 80 mole percent are selected from the group consisting of (meth)acrylic acid, CH═C(G)-C(═O)—Z—,
• wherein G is selected from the group consisting of H and CH3;
• and Z is a nitrogen or oxygen linking atom;
• C is a pendant moiety off a —CH2—C(G)- derived from polymerizing ethylenically unsaturated monomers of which at least 80 mole percent are selected from the group consisting of (meth)acrylic acid, CH═C(G)-C(═O)—Z—,
• wherein G is selected from the group consisting of H and CH3;
• and Z is a nitrogen or oxygen linking atom;
• (meth)acrylic acid and CH═C(G)-C(═O)—Z—, are defined to be (meth)acrylic acids and esters of acrylic acid where the ester has an alkoxy group that has from 1 to 25 carbon atoms and optionally includes an epoxide group or hydroxyl group,
• D is a moiety comprising polyether, polyester, polyacrylate, polyurethane, polyolefin and mixtures thereof having a number average molecular weight from about 300 to about 5000 g/mole and attached via a linking group to the polymer backbone or is derived from polymerizing a macromonomer comprising an ethylenically unsaturated group and a pendant polyether, polyester, polyacrylate, polyurethane, polyolefin and mixtures thereof having said 300 to 5000 g/mole molecular weight, K is from 1 to 50, L and J are each from about 0 to 499, and N is from 1 to 50, E is 1 or 2 and is the number of anchoring blocks, and F is 1 or 2 and is the number of solvent-solubilizing polymeric segments, with the proviso that if E is 1, F is 2 and if F is 1, E is 2.