This Communication reports two substituted polyacetylenes that can adopt helical structures of preferential screw sense in both emulsion (nanoparticle) and solution; however, the handedness of the macromolecular helices is just opposite in the two states. More interestingly, the helical screw sense of the polymers demonstrated a reversible transition between the two states. The unprecedented findings are of significant importance for acquiring new insights into helical polymers and for developing novel advanced chiral materials.
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