摘要 |
<p>An optionally substituted oligomer or polymer comprising a repeat unit of formula (I); wherein each Ar1 and Ar3 is the same or different and independently represents an optionally substituted aryl or heteroaryl; n is at least 1; Ar2 represents an optionally substituted aryl or heteroaryl comprising a linking ring to which the two nitrogen atoms are both directly linked; and at least one of Ar2 and either or both of Ar1 is substituted with at least one substituent.</p> |