The synthesis of poly(butadiene)diol-based polyurethanes with LC properties

8 Summary The PhD thesis is focused on the synthesis and characterization of low-molecular mesogenic thiols and poly(butadiene)diols and polyurethanes with LC side chains. Within the frame of this work, following tasks have been solved: Two groups of low-molecular compounds containing a biphenyl or an azobenzene as a rigid mesogenic part have been synthesized: N YNOSHXO SH Y = -H -OCH3 -O(CH2)3CH3 -O(CH2)7CH3 X = -H -CN Composition and structure of the prepared units were confirmed by elemental analysis and 1 H NMR spectroscopy. Thermal behavior, with the respect to the temperature-dependent mesophase formation, was studied by differential scanning calorimetry (DSC), polarizing optical microscopy (POM) and X-ray scattering techniques (SAXS, WAXS). It was found that the presence and the type of the substituent on the mesogenic core play a crucial role in the ordering of the thiol molecules into a LC phase. The thiols synthesized were grafted onto double bonds of the commercially available telechelic poly(butadiene)diol Krasol LBH 3 000 (declared Mn ~ 2 600 Da, Mw/Mn = 1.10). The addition reactions proceeded in the presence of radical initiator (AIBN). Molar ratio of thiol/double bonds varied within the range of 0.15 (resp. 0.2) to 1.0 for each type of the thiol. The structure of the resulted comb-like..