Poly(propyleneimine) dendrimers peripherally modified with mesogens

Poly(propyLeneimine)-based Liquid crystalline dendrimers (PPILCDs) with a r elatively flexible dendritic scaffold were successfully prepared by the Mic hael addition reaction of poly(propyleneimine)s with omega-(4'-cyanobipheny loxy)alkyl acrylate (1). The structures of PPILCDs were characterized by IR spectroscopy, H-1 NMR spectroscopy, and MALDI-TOF mass spectroscopy. PPILC Ds exhibit smectic liquid crystalline natures between -7 and +89 degrees C. The temperature range of the smectic phases expanded with increases in the generation of the dendritic core and the length of flexible spacers. The h omeotropic orientation was allowed to take place in PPILCD with the second- generation scaffold, when it was slowly cooled.