SIDE-CHAIN LIQUID-CRYSTAL POLYMERS OF 2,3-DISUBSTITUTED NORBORNENES VIA RING-OPENING METATHESIS POLYMERIZATION .1. INFLUENCE OF FLEXIBLE SPACER LENGTH M=2 TO 12 ON THE THERMOTROPIC BEHAVIOR
M. Ungerank et al., SIDE-CHAIN LIQUID-CRYSTAL POLYMERS OF 2,3-DISUBSTITUTED NORBORNENES VIA RING-OPENING METATHESIS POLYMERIZATION .1. INFLUENCE OF FLEXIBLE SPACER LENGTH M=2 TO 12 ON THE THERMOTROPIC BEHAVIOR, Macromolecular chemistry and physics, 196(11), 1995, pp. 3623-3641
-4-yl)oxy-n-alkyl]norborn-5-ene-2,3-dicarboxylates with alkyl chain le
ngths m = 2-12 were synthesized. Most of the monomers exhibit thermody
namically metastable liquid crystalline phases with respect to the cry
stalline phases. Polymers were prepared by ring-opening metathesis pol
ymerization (ROMP) using the molybdenum carbene initiator [Mo(CH-t-Bu)
(NAr) (t-BuO)(2)] (t-Bu = tert-butyl) with NAr = 2,6-diisopropylanili
ne. All polymers show thermotropic liquid crystalline phases. Results
on characteristic phases and the influence of the number of methylene
units m in the flexible spacer on the thermal behaviour (glass transit
ion temperature, isotropization temperature, odd-even effect, enthalpy
change) of these new side chain liquid crystal polymers (SCLCP's) are
given. They are compared to monosubstituted polynorbornene derivative
s and to SCLCP's with other backbones.