Graft copolymers, their preparation and use in capillary electrophoresis

A composition comprising a buffer and an effective amount of a poly(M1-g-M2) or a salt thereof, wherein:

• (a) each M1 has the formula (I):
• wherein each A1 is independently O, S or NX1;
• each of R1, R2, R3 and R4 is independently H, C1-C20 alkyl, C4-C12 cycloalkyl, C5-C12 aryl, C4-C12 heteroaryl, —(C1-C20 alkyl)(C5-C12 aryl) or —(C5-C12 aryl)(C1-C20 alkyl);
• each R5 is independently C1-C20 alkyl, C1-C20 heteroalkyl, C4-C12 cycloalkyl, C4-C12 heterocycloalkyl, C5-C12 aryl, C4-C12 heteroaryl, —(C1-C20 alkyl)(C4-C12 cycloalkyl), —(C4-C12 cycloalkyl)(C1-C20 alkyl), —(C1-C20 heteroalkyl)(C4-C12 cycloalkyl), —(C4-C12 cycloalkyl)(C1-C20 heteroalkyl), —(C1-C20 alkyl)(C4-C12 heterocycloalkyl), —(C4-C12 heterocycloalkyl)(C1-C20 alkyl), —(C1-C20 heteroalkyl)(C4-C12 heterocycloalkyl), —(C4-C12 heterocycloalkyl)(C1-C20 heteroalkyl), —(C1-C20 alkyl)(C5-C12 aryl), —(C5-C12 aryl)(C1-C20 alkyl), —(C1-C20 heteroalkyl)(C5-C12 aryl), —(C5-C12 aryl)(C1-C20 heteroalkyl), —(C1-C20 alkyl)(C4-C12 heteroaryl), —(C4-C12 heteroaryl)(C1-C20 alkyl), —(C1-C20 heteroalkyl)(C4-C12 heteroaryl), —(C4-C12 heteroaryl)(C1-C20 heteroalkyl), —(C1-C4 alkyl)qNH2, —(C1-C4 alkyl)qCONH2, —(C1-C4 alkyl)NHCONH2, —(C1-C4 alkyl)NHCOH or —(C1-C4 alkyl)qNHCOCH3, where each q is 0 or 1;
• and
• each X1 is independently H, C1-C20 alkyl, C4-C12 cycloalkyl, C5-C12 aryl, C4-C12 heteroaryl, —(C1-C20 alkyl)(C5-C12 aryl), —(C5-C12 aryl)(C1-C20 alkyl), —(C1-C4 alkyl)qNH2, —(C1-C4 alkyl)qCONH2, —(C1-C4 alkyl)NHCONH2, —(C1-C4 alkyl)qNHCOH or —(C1-C4 alkyl)qNHCOCH3, where each q is 0 or 1;
• (b) each M2 has the formula (II):
• wherein each A2 is independently O, S or NX2;
• each of R6, R7, R8 and R9 is independently H, C1-C20 alkyl, C4-C12 cycloalkyl, C5-C12 aryl, C4-C12 heteroaryl, —(C1-C20 alkyl)(C5-C12 aryl) or —(C5-C12 aryl)(C1-C20 alkyl);
• each R10 is independently H, C1-C20 alkyl, C1-C20 heteroalkyl, C4-C12 cycloalkyl, C4-C12 heterocycloalkyl, C5-C12 aryl, C4-C12 heteroaryl, —(C1-C20 alkyl)(C4-C12 cycloalkyl), —(C4-C12 cycloalkyl)(C1-C20 alkyl), —(C1-C20 heteroalkyl)(C4-C12 cycloalkyl), —(C4-C12 cycloalkyl)(C1-C20 heteroalkyl), —(C1-C20 alkyl)(C4-C12 heterocycloalkyl), —(C4-C12 heterocycloalkyl)(C1-C20 alkyl), —(C1-C20 heteroalkyl)(C4-C12 heterocycloalkyl), —(C4-C12 heterocycloalkyl)(C1-C20 heteroalkyl), —(C1-C20 alkyl)(C5-C12 aryl), —(C5-C12 aryl)(C1-C20 alkyl), —(C1-C20 heteroalkyl)(C5-C12 aryl), —(C5-C12 aryl)(C1-C20 heteroalkyl), —(C1-C20 alkyl)(C4-C12 heteroaryl), —(C4-C12 heteroaryl)(C1-C20 alkyl), —(C1-C20 heteroalkyl)(C4-C12 heteroaryl), —(C4-C12 heteroaryl)(C1-C20 heteroalkyl), —(C1-C4—(C1-C4 alkyl)qCONH2, —(C1-C4 alkyl)NHCONH2, —(C1-C4 alkyl)NHCOH or —(C1-C4 alkyl)qNHCOCH3, where each q is 0 or 1;
• and
• each X2 is independently H, C1-C20 alkyl, C4-C12 cycloalkyl, C5-C12 aryl, C4-C12 heteroaryl, —(C1-C20 alkyl)(C5-C12 aryl), —(C5-C12 aryl)(C1-C20 alkyl), —(C1-C4 alkyl)qNH2, —(C1-C4 alkyl)qCONH2, —(C1-C4 alkyl)NHCONH2, —(C1-C4 alkyl)qNHCOH or —(C1-C4 alkyl)qNHCOCH3, where each q is 0 or 1;
• (c) provided that at least one M1 is different from at least one M2.