er group, preferably unsubstituted monovalent alkyl or aryl groups, or are the following nitrogen-containing structure: with the proviso that at least one of R1, R3, and R8 are according to Structure IV, wherein R9 is a divalent alkyl group such as ???(CH2)s??? where s is from 1 to 10, preferably 3 to 6 and most preferably 3;