Multiple Segmental Processes in Polymers with <i>cis</i> and <i>trans</i> Stereoregular Configurations

Abstract

Altering the stereochemistry of a single double bond in the side group of a polymer resulted in systems with unprecedented local dynamics. These include (i) the appearance of three segmental processes in the <i>cis</i>-polymers all with Vogel-Fulcher-Tammann (VFT) temperature dependence, (ii) the low steepness index associated with fragility, <i>m</i>, and (iii) the lowest pressure coefficient of <i>T</i>_g, d<i>T</i>_g/d<i>P</i>, ever reported for polymers. We show that it is the inability of the <i>cis</i>-polymer to pack the side groups efficiently that controls the dynamics. Furthermore, the <i>trans</i>-polymers have the ability to crystallize. The wealth of dynamics reflects the <i>cis</i>/<i>trans</i> stereochemistry and the presence of different dipoles at specific positions sampling both the side group and backbone dynamics.