It is shown that the addition of 2 to 6 wt.%of a chiral dopant (CD) to a series of nematic copolymers (Pn) induces blue and cholesteric mesophases. The mesomorphic behaviour of various CD + Pn mixtures is investigated by polarized optical microscopy and the phase transition temperatures are determined by DSC measurements. Deuterium NMR spectra are recorded as a function of temperature within the mesophases and the spectral line shapes characteristic of different local orientational order parameters and orientational ordering processes of molecules in a magnetic field are observed depending on temperature, heating or cooling process, chiral dopant concentration, copolymer composition, and magnetic field strength.
|Autori:||BARMATOV E.; CALUCCI L.; CATALANO D.; CHIEZZI L.; VERACINI C.A.; FODOR-CSORBA K.|
|Titolo:||H-2-NMR of the induced Chiral Phases of Acrylate-Metacrylate Liquid Crystalline Polymers|
|Anno del prodotto:||2005|
|Appare nelle tipologie:||1.1 Articolo in rivista|