Dispersants with multiple aromatic imide anchor groups

A polymer comprising a polymer chain having at least one imide group, wherein each imide group is chemically bonded to an aromatic ring (either a single aromatic ring or a fused aromatic ring), the polymer is represented by Formula (1):

• wherein each variable is independently
• R1 may be a non-hydrogen substituent on Q ring in any position available for bonding to a substituent group and R1 may be independently represented by one or more of —H, or an electron withdrawing selected from the group —NO2, SO2NR′2, —C(O)R′, —SO3M, halo, —NH2, and —OR, or an electron releasing alkyl group of 1 to 3 carbon atoms, the number of non-H substituted groups on Q defined by a may be 0 to 2;
• wherein M can be H, a metal cation, NR′4+, or mixtures thereof;
• R′ can be —H, an optionally-substituted alkyl typically containing 1 to 20, and the substituent of R′ may be hydroxyl or halo or mixtures thereof;
• Q may be a fused or non-fused aromatic ring containing 4n+2 π-electrons, wherein n=1 or more, and Q may be bonded to the imide group in such a way to form a 5 or 6 membered imide ring;
• b is 1 or 2, and when b is 2 the imide group is a side chain attached to Pol by two chemical bonds;
• d is 1, 2, or 3;
• this means that there is the possibility of 1 to 3 imide groups attached to R2 at different carbon atoms of R2;
• R2 may be a C1 to C20 hydrocarbylene group or a C1 to C20 hydrocarbonylene group or mixtures thereof;
• R2 may include oxygen and/or nitrogen atoms wherein there is at least 2 carbon atoms per every oxygen or nitrogen of R2, these would include ether, ester, and amide type linkages in R2;
• W′ is a nitrogen atom, an oxygen atom or a direct bond;
• when b is 2 then one of the W′ can be derived from a secondary amine reacted with said isocyanate and be in the R2 linking group between the imide and the other W′ group, when b is 2 each W′ group can be the same or different;
• Pol is a polyurethane comprising at least two urethane and/or urea linkages and at least one of polyether, polyester, polyolefin and polyacrylate terminal chains, or mixtures of said terminal chains;
• and
• w is 1 or more.