Synthesis and curing of liquid crystalline epoxy resin based on asymmetric mesogen

Abstract

A novel liquid crystalline epoxy resin (LCER) derived from asymmetric mesogen unit was synthesized. Its structure and liquid crystalline behavior were characterized by hydrogen nuclear magnetic resonance (H-NMR), differential scanning calorimetry (DSC), polarized optical microscopy (POM). The results indicated that the LCER converted to a nematic phase at 85 C during heating and finally became isotropic at 145 C. The curing behavior and phase behavior of the LCER with 4,4 0 -diaminodiphenyl methane and methyl hexahydrophthalic anhy-dride were also studied by DSC and POM, respectively. Their apparent activation energy (E a ) was evaluated according to the Ozawa's isoconversional method. The results suggested that autocatalytic reaction had occurred in these two systems.

Synthesis, characterization, and mechanical properties of a novel terphenyl liquid crystalline epoxy resin

“…The effect of the backbone chain orientation on their unique and excellent properties, such as high glass transition temperature (T g ), fracture toughness, bonding property, [1][2][3][4][5][6][7][8][9] and thermal conductivity, [10][11][12][13] has been studied in detail, and a variety of novel LC epoxy resins, epoxy monomers, and curings have been investigated. [13][14][15][16][17][18][19][20][21][22] The relationship between the ordered structure and the physical properties of LC epoxy curings has also been studied. The mesogenic groups of the LC epoxy resins used in these studies contained a Schiff base.…”

“…Liquid crystalline (LC) epoxy resins have a LC phase‐temperature region because of the interaction of the mesogenic groups located along the backbone of the resin. The effect of the backbone chain orientation on their unique and excellent properties, such as high glass transition temperature ( T g ), fracture toughness, bonding property, and thermal conductivity, has been studied in detail, and a variety of novel LC epoxy resins, epoxy monomers, and curings have been investigated …”