Side-chain liquid-crystalline poly(ketone)s: effect of spacer length, mesogen type and mesogen density on mesomorphic behavior

A series of novel side chain liquid crystalline polysiloxanes containing cyano‐ and cholesterol‐terminated substituents: Where will the structure‐dependence of terminal behavior of the side chain reappear?

“…Further analysis and probe showed that d (100) ≈ L m + 2 L s , where L s (1.07 nm) is the calculated length of the spacers from the O atom in the ether groups to the Si atom in the backbones, and L m (1.28 nm) is the calculated length of the achiral mesogenic cores from the O atom in the ether groups to the last N atom of the achiral side chains, respectively. Additionally, previous reports have revealed that the dipole interaction of the strong polarity cyano substituent could induce the side chains to organize in antiparallel pairs to force the cyano away from each other and to minimize the system energy, which played a decisive role on the self‐organization of the molecule . Combining the comprehensive analysis and judgment of above results, as shown in Scheme , we speculated that for this series of polysiloxanes‐containing cyano‐terminated side chains, a monolayer SmA phase with side chains partially interdigitated was self‐assembled, in which the layer period was dominated by the achiral side chains with cyano unit.…”

“…By replacing the CH 3 side chain groups with polar CF 3 groups, Lee et al found the similar results. Sudhölter et al and Chen et al reported that a drastic change in mesogen phase structures was occurred when cyano group was used instead of methoxy group as the terminal group. Zhou et al synthesized a series of mesogen‐jacketed liquid crystalline polymers (MJLCPs) with asymmetric substitutions and found that carboxylic acid terminated asymmetric polymers formed a double layer smectic A phase, while the corresponding alkyl terminated polymers showed no liquid crystallinity or exhibited columnar phase.…”

Functionalization of aliphatic polyketones

“…Rieger et al investigated the infl uence of mesogen type and density on the mesomorphic behavior of side-chain liquid crystal poly(ketone)s. 13 The monomers employed were methoxyazabenzene mesogen, methoxybiphenyl mesogen, and cyanobiphenyl mesogen, as shown in Scheme 2 .…”

Coordination–insertion copolymerization of polar vinyl monomers by palladium catalysts

“…Drent et al used a catalyst consisting of Pd(OAc) 2 and DPPP for the co‐ and terpolymerization of CO with functionalized olefins such as methyl undec‐10‐enoate, undec‐10‐enoic acid, undec‐10‐en‐1‐ol, but‐3‐en‐1‐ol, allyl acetate, and 6‐chloro‐1‐hexene 46. Rieger et al reported that a preformed dicationic Pd complex, [Pd(DPPP)(CH 3 CN) 2 ](BF 4 ) 2 , is an effective catalyst precursor for using functionalized allylbenzene derivatives,47 highly functionalized olefins bearing a benzo‐15‐crown ether,48 mesogenic units,49 monosaccharide,50 amino acids, and steroids 51. A dicationic palladium complex bearing 1,10 phenanthroline was employed for the terpolymerizations of undec‐10‐enoic acid or undec‐10‐en‐1‐ol with styrene and CO 52.…”