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A series of bowlic cyclotriveratrylenes(CTV) with peripheral groups with different lengths were synthesized.These compounds were investigated by diferential scanning calorimetry and hot stage coupled polarizing microscopy.Several CTV derivatives show thermotropic liquid crystalline properties.The experimental results of their thermotropic liquid crystalline behavior indicate that the clear points,the entropy changes of melting points,the crystallization temperatures,and their entropy changes all exhibited an evident odd-even effect except the melting points,which decreased monotonously with the increase of the length of the alkoxy groups.The parameter values of CTVs with even number carbon atoms were larger than those of CTVs with odd number.When the length of alkoxyl chains was even longer,a monotonous decrease occured.Nevertheless,in the case of the entropy changes of both melting points and crystallization temperatures,the effect was valid for all the six species,and therefore,the whole curves presented as a zig-zag form.
A series of bowlic cyclotriveratry lenes (CTV) with peripheral groups with different lengths were synthesized. These compounds were investigated by diferential scanning calorimetry and hot stage coupled polarizing microscopy. Sevral CTV derivatives show thermotropic liquid crystalline properties. The experimental results of their thermotropic liquid crystalline behavior indicate that the clear points, the entropy changes of melting points, the crystallization temperatures, and their entropy changes all exhibited an evident odd-even effect except the melting points, which decreased monotonously with the increase of the length of the alkoxy groups. the parameter values of CTVs with even number carbon atoms were larger than those of CTVs with odd number. The length of alkoxyl chains was even longer, a monotonous decrease occured.Nevertheless, in the case of the entropy changes of both melting points and crystallization temperatures, the effect was valid for all the six species, and therefore, the w hole curves presented as a zig-zag form.