B is a radical selected from the group consisting of an alkyl of 1-7 carbon atoms, a halogen, a nitrogen, and a moiety which is linked to the 2-position of the phenyl that is neither the phenyl linked to the same ethylene carbon as B, nor the phenyl substituted by the radical containing the permanently ionic group G, and which is selected from the group consisting of ???CH2C(R1)(R2)??? and ???CH2?