and find that we can access three completely different assembly pathways by varying the solution aggregate structures. When solution coating is performed at near equilibrium conditions (esp. in the evaporation regime), polymer assembly is driven by concentration increase due to solvent evaporation. We therefore investigate equilibrium solution state at progressively increased solution concentrations (60, 130 and 200 mg ml -1 ) prepared using dropand-dry method (see experimental details in SI). We use a combination of optical and electron microscopy, circular dichroism (CD) spectroscopy to characterize the solution structures at elevated concentrations. As shown in Figure , when dissolved in DCB and other mutual solvents (Figure ), PII-2T nanofiber aggregates form a series of lyotropic LC mesophases upon progressively increasing solution concentration . When the solution surpasses a threshold concentration at ~60 mg ml -1 , the liquid crystals first nucleate in confined droplets commonly referred to as nematic tactoids. Further increasing solution concentration to 130 mg ml -1 causes tactoids to merge into a continuous domain which appears birefringent under CPOM. This domain consists of aligned twisted fibers as shown by the SEM image of freeze-dried samples (Figure ). The chirality of this continuous liquid crystal phase is evidenced by the CD signal (shown as insets of Figure ). This phase is defined as a twist-bent mesophase . At an even higher concentration of 200 mg ml -1 , another chiral mesophase appears and exhibits a twinned morphology wherein a few micron periodicity is observed in its stiped texture. These mesophases discovered in DCB solutions are comprised of aligned polymer fiber aggregates instead of single polymers according to SEM shown in Figure . Therefore, we deduce that balanced backbone and side chain interactions conferred by mutual solvents is important to forming such liquid crystals. We then discover that such LC mesophases are absent from the two selective solvents due to the lack of nanofiber aggregates serving as the essential precursor to those LCs. As shown in Figure , the amorphous aggregates persist upon further increasing the solution concentration in CN at 115 °C. While the aggregates remain unobservable under the optical microscope, TEM images of samples freeze-dried from concentrated solutions resemble that of 10 mg ml -1 solution except that the aggregates densify due to higher solution concentrations. These solutions in CN show no appreciable CD signals due to the absence of chiral LC mesophase. In decane solutions, increasing solution concentration only leads to formation of larger micron-scale agglomerates and do not lead to emergence of new mesophases (Figure ).