Nature of Flexible Spacer and its Length

According to the previous discussion it is found that increasing the degree of polymerization decreases the entropy of the system and if the monomeric structural unit exhibits a virtual or monotropic or mesophase, the resulting polymer should most probably exhibit a monotropic or mesophase. Alternatively, if the monomeric structural unit displays a mesophase, the polymer should display a mesophase that is broader. It is also possible that the structural unit of the polymer exhibits more than one virtual mesophase and therefore at high molecular weights the polymer will inerease the number of its mesophases. All these effects have been observed in various systems. 

The length of the flexible spacer determines the nature of the mesophase. Long spacers favour smectic phases while short spacers favour nematic phases. This effect is similar to that observed in low molar mass liquid crystals. 

---