Synthesis and phase behavior of liquid crystalline poly(3-n-ALKYL-4-hydroxybenzoates)

A series of 3-n-alkyl substituted poly(4-hydroxybenzoates) were prepared by melt-polycondensation of the corresponding monomers. The length of the alkyl side chains was varied in the range of 3 to 18 carbon atoms. The average degree of polymerisation (DP) was determined by ¹H NMR end-group analysis. The thermal behavior of the polymers was studied by differential scanning calorimetry (DSC) and polarising microscopy (PM). Structural investigations of oriented and not oriented samples were performed by means of wide angle X-ray scattering (WAXS). The density of the polymers was measured by gradient column technique.