The divergent synthesis of a new carbosilane liquid crystalline (LC) dendrimer (D2) of the second generation is described. Thirty six 4- butoxyazobenzene groups (MS) are used as mesogenic fragments and attached in its periphery. Structure and properties of D2 were characterized by elemental analysis, 1~H NMR, MALDI-TOF-MS, IR, UV, polarizing optical micrograph, DSC and WAXD. Similar to MS, D2 is a nematic liquid crystal. The mesomorphic state of the dendrimer of second generation (D2) depends on that of mesogenic units. Phase behavior of D2 in LC state is K85N107I103N69K. The melting point of D2 is 27-41℃ less than that of MS, the clearing point of D2 is 17-18℃; less than that of MS and the mosophase region of D2 is 10 -23 ℃ greater than that of MS. The melting point of D2 is 2-3℃ greater than that of Dl, the clearing point of D2 is 26 -29℃ less than that of Dl and the mesophase region is 29-31℃ less than that of Dl. Six extinguished brushes emanating from a stationary point were observed, corresponding to the high-strength disclination of S = + 3/2 of dendrimer D2.

Key words: carbosilane, LIQUID CRYSTAL, BENZENE AZO COMPOUNDS, ELEMENTAL ANALYSIS, IR, UV