Mesogen-Jacketed Liquid Crystalline Polymers with a Polynorbornene Main Chain: Green Synthesis and Phase Behaviors

Abstract

We synthesized a new series of MJLCPs with a polynorbornene main chain, PNbnPT (n = 8, 10, 12, 14, 16, 18, which is the number of carbons in the side-chain alkyl tails), through ring-opening metathesis polymerization and investigated their phase behaviors. The monomers were facilely synthesized in satisfactory yields through a key intermediate, N-(2,5-dicarboxylphenyl)-cis-5-norbornene-exo-2,3-dicarboximide. Differential scanning calorimetry, polarized light microscopy, and wide-angle X-ray diffraction results demonstrate that the phase behavior of PNbnPT is strongly dependent on the alkyl-tail length. Polymers with relatively short alkyl tails, PNb8PT and PNb10PT, are amorphous in the whole temperature range before degradation. When the alkyl-tail length increases, PNbnPTs (n = 12, 14, 16, 18) develop into the smectic A phase, and the degree of order increases with increasing alkyl-tail length. The synthetic pathway for MJLCPs with a polynorbornene main chain in this work is more robust and greener than those reported to the best of our knowledge. And MJLCPs with a polynorbornene main chain show quite different phase behaviors compared with those with a polyethylene backbone, and they may be used to create fascinating functional materials.

Influence of main chain on the phase behaviors of side‐chain liquid‐crystalline polymers with triphenylene mesogens of long alkyl tail substituents

“…N‐4‐benzoate‐ cis −5‐norbomene‐exo‐2,3‐dicarboximide was synthesized according to a reported procedure . N‐4‐benzoate‐ cis −5‐norbomene‐exo‐2,3‐dicarboximide (1.0 g) and HO‐R (1.0 g, 0.69 mmol) were dissolved in dry CH 2 Cl 2 (100 mL) at room temperature.…”

Side Chain Liquid Crystalline Polymers: Advances and Applications

“…With the consideration of the high tolerance of functional groups e.g. fullerene, the convenient synthesis by ring-opening metathesis polymerization (ROMP), (Ball et al 2006;Bielawski and Grubbs 2007) and the excellent properties of polynorbornenes, (Maier 2001;Piunova et al 2013), the exploration of MJLCPs with polynorbornene main chain, is of great interest (Zhu et al 2014). …”

Synthesis and properties of poly(norbornene)s with lateral aramid groups

“…Furthermore, these reports mainly focused on using terephthalic acid, polyphenyl, or phenyl alkynyl oligomers as rigid rods. 12,13 The aim of this work was the synthesis of comb-like poly(norbornene)s carrying lateral rod-like aramid groups and the investigation of how the properties of such materials can be controlled by exploiting different types of non-covalent interactions, which are a powerful tool for supramolecular organization. In this paper, we present the synthesis of statistical copolymers made from norbornenebased monomers carrying either tri( p-benzamide) rods or aliphatic side chains.…”