Spacer length and molecular weight variation on ferroelectric liquid crystalline polymers

The influence of the spacer length (n = 2, 6, 8 and 11 methylene groups) on the polymorphism and the ferroelectric properties of liquid crystalline side‐group polyacrylates with a 4‐[(R)‐4‐(1‐methylheptyloxy)‐4′‐biphenylyloxycarbonyl]phenoxy moiety was studied. Various molecular weights were obtained from the polymers with n = 8 and n = 11. All the polymers show SmC* phases. A SmC* phase polymorphism was even found for most of the polymers. In some of these SmC* phases, no ferroelectric properties could be measured. The structural differences between the SmC* phases and their influence on the appearance of the ferroelectric properties are not yet clear. However, a SmC̃* phase was put in evidence, revealing a tendency to a chevron‐like ordering which may explain the complex SmC* polymorphism of these systems.