Optical activity preferential screw sense copolymers

For example, the sergeants and soldiers experiment features a preferential screw-sense helical amplification in optical active copolymers with racemic helical structures named by Green et al. [17,18], This effect means that a small portion of enantiopure chiral side groups determines the overall screw sense (P or M) of the helical main chain bearing a majority of achiral side groups, and a population of helicity with one preferential screw-sense is nonlinearly amplified as a function of the chiral impurity. Since the first report of this phenomenon in poly-a-olefin copolymers by Pino et al. [21],... 

Another significant helical amplification in optically active copolymers with preferential screw-sense helicity is known as the majority rule phenomenon [ 17,18]. In this case, the screw sense of a helical main chain bearing nonracemic chiral side groups is controlled by the ee only and a population of preferential screw-sense helicity and optical activity were nonlinearly amplified by ee of chiral side groups. Since Pino et al. first reported this phenomenon in poly-a-olefins made of vinyl co-monomers bearing nonracemic chiral moieties [21], this majority rule has already been established in stiff polyisocyanates bearing a nonracemic chiral side chain [17,18]. 

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