•A new series of MCSCLCPs containing MJLCP main chains prepared via hydrogen bonding.•Phase behavior of complex strongly affected by content of H-B donor and rigidity of side-chain core in polymer H-B acceptor.•Complex forming hierarchical nanostructures including one of whole polymer chain and the other of triphenylene moieties.Main-chain/side-chain combined liquid crystalline polymers (MCSCLCPs) are usually difficult to synthesize and their degrees of polymerization are relatively low, which bring difficulties in studying their structure–property relationships. In order to solve this problem, we prepared a new series of MCSCLCPs containing mesogen-jacketed liquid crystalline polymer (MJLCP) main chains via hydrogen-bonding (H–B). A pyridine derivative with a triphenylene (Tp) unit is the H–B acceptor. In addition to the temperature dependence, the phase behavior of the resulting complex is strongly influenced by the content of the H–B acceptor and the rigidity of the side-chain core of the MJLCP. The resulting complexes exhibit different phase structures: (1) a columnar nematic phase or a smectic A (SmA) phase formed by the supramolecular MJLCP chain as a whole; (2) hierarchical nanostructures including a hexagonal columnar phase or a SmA phase of the whole polymer chain plus a discotic nematic phase associated with the Tp moieties.

A new fluorinated poly(aryl ether) with reactive benzocyclobutene groups as the side chain was successfully synthesized. This polymer showed a number-average molecular weight (Mn) of 200 000 and had good solubility and film-forming ability. After being postpolymerized at high temperature (>200 °C), the polymer film converted to a cross-linked network structure, which was insoluble in the common organic solvents. Such results suggest that the postpolymerization is an efficient way to achive the balance between the solubility and the solvent resistance of the polymer. TGA data showed that the postpolymerized polymer had a 5 wt % loss temperature at 495 °C and a residual of 61% at 1000 °C under N2. The cross-linked film also exhibited good dielectric properties with an average dielectric constant of about 2.62 in a range of frequencies from 1 to 30 MHz. With regard to the mechanical properties, the cross-linked film had hardness, Young’s modulus, and bonding strength to a silicon wafer of 1.22, 8.8, and 0.89 GPa, respectively. These data imply that this new polymer may have potential applications in the electrical and microelectronics industry.Keywords: benzocyclobutene dielectric constant; fluorinated poly(aryl ether)s; postpolymerization; synthesis; thermostability

Liquid crystalline (LC) polymers with a shish-kebab-type moiety on their cross-conjugated (p-phenylene)s-poly(pphenylenevinylene) s main chains were synthesized through Gilch polymerization in order to develop a kind of polymers available for linearly polarized white-light-emitting from single chain. In this system, the 2,5-bis(4′-alkoxyphenyl)benzene as the “kebabs” connects with poly(p-phenylenevinylene) (PPV) main chain backbone using its molecular gravity center and the PPV as the “shish” or “skewer” (the “shish-kebab”). The polymers possess desirable properties such as excellent solubility and liquid crystalline properties. To drop the “kebabs” of the 2,5-bis(4′-alkoxyphenyl)benzene into the orientation microgroove of aligned polyimide film, not only the “shish” of polymer main chain can be aligned by the virtue of orientation of “kebabs” but also the uniform cross-conjugated structure between the “kebabs” and “shish” can be broken. Then, the alignment of the polymer main chain showed yellow light emission and was also accompanied by orientation of the LC side chains showing blue light emission, this gave rise to a notable linearly polarized white fluorescence.