The results of the previous section show that multi-chain P(NDI2OD-T2) aggregates in which pairs of chain do not fully overlap are sufficiently stable in the poor solvent that they do not separate on the time scale of further aggregation. A further condition that must be satisfied for the build-up of extended rodlike aggregates is that the chains must aggregate before they are able to fold into more compact conformations. Thus, we turn our attention to the relative rates of single-chain folding and multichain aggregation.