Tuning the Chirality of Block Copolymers: From Twisted Morphologies to Nanospheres by Self‐Assembly

New advances into the chirality effect in the self‐assembly of block copolymers (BCPs) have been achieved by tuning the helicity of the chiral‐core‐forming blocks. The chiral BCPs {[NP( R )‐O 2 C 20 H 12 ] 200− x [NP(OC 5 H 4 N) 2 ] x }‐ b ‐ [NPMePh] 50 (( R )‐O 2 C 20 H 12 =( R )‐1,1′‐binaphthyl‐2,2′‐dioxy, OC 5 H 4 N=4‐pyridinoxy (OPy); x =10, 30, 60, 100 for 3 a – d , respectively), in which the [NP(OPy) 2 ] units are randomly distributed within the chiral block, have been synthesised. The chiroptical properties of the BCPs ([ α ] D vs. T and CD) demonstrated that the helicity of the BCP chains may be simply controlled by the relative proportion of the chiral and achiral (i.e., [NP( R )‐O 2 C 20 H 12 ] and [NP(OPy) 2 ], respectively) units. Thus, although 3 a only contained only 5 % [NP(OPy) 2 ] units and exhibited a preferential helical sense, 3 d with 50 % of this unit adopted non‐preferred helical conformations. This gradual variation of the helicity allowed us to examine the chirality effect on the self‐assembly of chiral and helical BCPs (i.e., 3 a – c ) and chiral but non‐helical BCPs (i.e., 3 d ). The very significant influence of the helicity on the self‐assembly of these materials resulted in a variety of morphologies that extend from helical nanostructures to pearl‐necklace aggregates and nanospheres (i.e., 3 b and 3 d , respectively). We also demonstrate that the presence of pyridine moieties in BCPs 3 a – d allows specific decoration with gold nanoparticles.