The helical sense and elongation of a helical polymer that bears the 4-ethynylanilide of (R)-α‑methoxy-α-phenylacetic acid [m-(R)-1] can be tuned by the action of the two components of tetraalkylammonium-anion salts. Thus, while the supramolecular PPA-anilide/anion interaction creates a chiroptical switch, inducing either P or M helical senses in the poly(phenylacetylene) (PPA) depending on the nature of the anion —P helix: fluoride (F⁻) or cyanide (CN⁻); M helix: acetate (OAc⁻), benzoate (OBz⁻) or azide (N₃⁻)—, deprotonation of the anilide group by these anions in dry conditions makes it possible to play with the elongation of the PPA, depending on the size of the tetraalkylammonium group, which results in a colorimetric switch. Thus, a color change from yellow to deep red is obtained by deprotonation of the anilide group when a tetraabutylammonium salt is used, while yellow/light-red and yellow/orange color changes are obtained when the size of the tetraalkylammonium group is reduced. Structural and mechanistic studies confirm that the color change occurs when the counterion accommodates itself close to the pendant group once the anilide hydrogen is removed. This PPA/tetraalkylammonium association is responsible of elongation changes in the PPA and therefore on the conjugation of the polyene backbone that is accompanied with color changes. Moreover, this colorimetric switch also operates in the solid state and can be switched in a vacuum/air moisture cycle.

带有( R )-α-甲氧基-α-苯乙酸[m-( R ) -1 ]的4-乙炔基苯胺的螺旋聚合物的螺旋方向和伸长率可以通过四烷基铵-阴离子盐。因此，虽然超分子 PPA-苯胺/阴离子相互作用产生了手性转换，根据阴离子的性质，在聚苯乙炔 (PPA) 中诱导P或M螺旋感 - P螺旋：氟 ( F ^- ) 或氰化物(CN ^- ); M螺旋：醋酸盐（OAc ^-）、苯甲酸盐（OBz ^-）或叠氮化物（N ₃ ^-)-，在干燥条件下这些阴离子对苯胺基团的去质子化可以影响 PPA 的伸长率，这取决于四烷基铵基团的大小，这会导致比色转换。因此，当使用四丁基铵盐时，通过苯胺基团的去质子化获得从黄色到深红色的颜色变化，而当四烷基铵基团的尺寸减小时获得黄色/浅红色和黄色/橙色颜色变化。结构和机理研究证实，一旦去除了苯胺氢，反离子将自身容纳在侧基附近时就会发生颜色变化。这种 PPA/四烷基铵缔合负责 PPA 中的伸长率变化，因此负责伴随颜色变化的多烯主链的共轭。而且，