Liquid Crystalline Polymers XIII Main Chain Thermotropic Copoly (Arylidene-Ether)s Containing 4-Teriary Butyl-Cyclohexanone Moiety Linked with Polymethylene Spacers

Abstract

A new homologous series of thermotropic liquid crystalline copoly(arylidene-ether)s based on 4-teriary butyl cyclohexanone moiety were synthesized by solution polycondensation of 4,4'-diformyl-α,ω-diphenoxyalkanes, I a-d or 4,4'diformyl-2,2'-dimethoxy-α,ω-diphenoxyalkanes II a-d with the 4-teriary butyl-cyclohexanone III and cyclopentanone. A model compound IV was synthesized from the monomer III with benzaldehyde and characterized by elemental and spectral analyses. The inherent viscosities of the resulting polymers were in the range 0.22 -0.92 dI/g. All the copoly(arylidene-ether)s were insoluble in common organic solvents but dissolved completely in concentrated H 2 SO 4 and formic acid. The mesomorphic properties of these polymers were studied as a function of the diphenoxyalkane space length. Their thermotropic liquid crystalline properties were examined by DSC and optical polarizing microscopy and demonstrated that the resulting polymers form nematic mesophases over wide temperature ranges. The thermogravimetric analyses of those polymers were evaluated by TGA and DSC measurements and correlated to their structural units. X-ray analysis showed that copolymers having some degree of crystallinity in the region 2 = 5° -60°. In addition, the morphological properties of selected examples were tested by Scanning electron microscopy.

Photoactive poly(hydroxyl-amino ether)s based on 4-methyl-cyclohexanone and 4-tert-butylcyclohexanone moieties in the main chain: synthetic methodology and characterization

“…Over the last two decades, photocrosslinkable polymers have potentially interesting applications, such as photocurable materials, surface coatings, printing inks, printing plates in photo recorders [37] and digital computers [38][39][40][41][42][43]. As a continuation of our study on the synthesis and properties of different polymers based on diarylidenecycloalkanones moieties in the main chain [44][45][46][47][48][49][50][51][52][53][54], two new series of polymers possessing photoresponsive properties were prepared. These series are poly(hydroxyl-amino ether)s containing 4-methylcyclo-hexanone and 4-tertbutylcyclohexanone moieties.…”

Preparation of poly(2‐anilinoethanol) containing azobenzene group under electrical field and its liquid crystalline properties investigation

“…[4] On the basis of the way in which mesogens are connected to the polymer backbones, SC-LCPs can be categorized into either "side end-fixed" or "side-on-fixed" type. [5] According to Finkelmann et al, [6] the flexible spacer entered between the main chain and the mesogenic unit is indispensable in order for a SC-LCP to achieve liquid-crystalline (LC) phase as it decouples the interaction of side chain and polymer backbone, which spoil the ordered packing of the side mesogens. Recently, a novel liquid-crystalline (LC)-conducting polymer synthesized by introducing LC group into pyrrole monomer and polymerizing it with FeCl 3 .…”