| Different discotic liquid crystals based on triphenylene including 2,3,6,7, 10,11-hexapentaloxytriphenylene,2,7-dicarbetboxy-3,6,10,11-tetrapentyloxyt riphenylene,a series of triphenylene-based liquid crystals which combined one discotic-shaped mesogen and three rod-shaped mesogens through alkyl,two triphe nylene-based hyperbranched ester and ether macromolecule was synthesized and a triphenylene-calixarene compound named 25,27-2-calix[4]arene-26,28-2(-valerate) triphenylene ester were synthesized.The chemical structrures of these materials synthesized here were characterized by using IR,1HNMR,13CNMR,elernentary analysis.The molecular weights and the distribution of the two hyperbranched discotic ester and ether were also characterized by using GPC.The degree of thehyperbranched discotic ester was 0.85.The liquid crystalline properties of the materials synthesized here were characterized by using polarized optical microscopy,differential scanning calorimetry and x-ray diffractometry.2,7-dicarbetboxy-3,6,10,11-tetrapentyloxytriphenylene displayed columnar phase during cooling process at the temperature range from 99℃to 160℃and the columnar phase can be preserved even at room temperature. The series of triphenylene-based liquid crystals showed multi-mesomorphism withchanging the carbon atoms of the linked alkyl and odd-even effect and the odd-even effect should be the character of rod-like liquid crystal,it can be concluded that these disc-rod molecules behaved as rod-like and the triphenylene was only the linkage of the three rod-like moieties,but the columnar phase of sample with 11 carbon number spacer can be induced by TNF.The hyperbranched discoticether showed columnar phase that was disordered to some degree and the hyperbranched discotic ester showed nematic phase.25,27-2-calix[4]arene -26,28-2(-valerate) triphenylene ester showed only crystalline phase.We have fabricated poly methyl methacrylate /2,3,6,7,10,11- hexapentaloxytrip henylene composite nanotubes by wetting an ordered porous anodic alumina temp late.The nanotubes formed by the template were characterized by SEM and XR D showed that the nanotubes had a diameter distribution from 150-200nm and the thickness of the walls of the nanotube is 20-30nm.The results showed that the geometric confinement can promote the growth of the discotic liquid crystal columns along the long axes of the nanotube.The charge carrier mobilities of 2, 3,6,7,10,11-hexapentyloxytriphenylene,2,7-dicarbetboxy-3,6,10,11-tetrapentyloxytriphenylene, the hyperbranched ester and the composite of 2,3,6, 7,10,11- hexapentyloxytriphenylene and the hyperbranched ester were measured using time-of-flight method and they were 1.47×10-4cm2v-1s-1,1.1×10-4cm2v-1s-1, 5.74×10-4cm2v-1s-1,respectively.The results were lower 1-2 magnitude than those reported in other references due to the lower orientational orders of these discotic molecules in the film,but they also higher 1-2 magnitude than general hole transport molecules with a charge carrier mobilities of 10-5-10-6 cm2v-1s-1.
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