Atom Transfer Radical Polymerization (ATRP) has been applied to synthesize liquid crystalline methacrylic polymers having three-arms star structure, starting from a central core of C3 symmetry. By just changing the duration of the polymerization process, macromolecules having distinct average chain lengths with low polydispersity values and well defined end-groups have been obtained. All the obtained star-shaped polymers, characterized by differential scanning calorimetry and polarized optical microscopy, exhibit smectic and nematic liquid-crystalline phases on heating, with transition temperatures strongly dependent on the average polymerization degree, and high cleaning points.
Synthesis by ATRP and properties of liquid crystalline three-armed star polymers containing azobenzene chromophores
ANGIOLINI, LUIGI;BENELLI, TIZIANA;GIORGINI, LORIS;SALATELLI, ELISABETTA;ZUCCHERI, TOMMASO
2007
Abstract
Atom Transfer Radical Polymerization (ATRP) has been applied to synthesize liquid crystalline methacrylic polymers having three-arms star structure, starting from a central core of C3 symmetry. By just changing the duration of the polymerization process, macromolecules having distinct average chain lengths with low polydispersity values and well defined end-groups have been obtained. All the obtained star-shaped polymers, characterized by differential scanning calorimetry and polarized optical microscopy, exhibit smectic and nematic liquid-crystalline phases on heating, with transition temperatures strongly dependent on the average polymerization degree, and high cleaning points.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
