π-Gels with Diverse Architectures and Properties
소속 :
연사 : Ayyappanpillai Ajayaghosh(NIIST, CSIR)
일시 : 2011-04-27 17:00 ~
장소 : 500동 310호
일 시 : 2011년 4월 27일, 5:00 PM
장 소 : 500동 310호
-Abstract-
The “bottom-up” self-assembly of organic molecules utilizes noncovalent interactions such as hydrogen bonding, -stacking, van der Waals, dipolar and electrostatic interactions. Rational designs of molecular structures that engage in noncovalent interactions are crucial for the creation of nano- to microsized assemblies with controlled shape and size. For the past several years we have been investigating the self–assembly of -conjugated systems such as p-phenylenevinylenes, p-phenyleneethynylenes and thienylenevinylenes. These molecules self-assemble from nonpolar solvents leading to a variety of supramolecular architectures such as tapes, helices, particles and toroids as shown below. At higher concentrations, they form organogels comprising of entangled fibers of nano- to micrometers in size. It has been found that the nature of the conjugated backbone and the attached functional groups play an important role in controlling the morphology of the supramolecular structures. An interesting feature of these self-assemblies is their strong fluorescence which is sensitive to temperature and solvent polarity. In addition, they strongly interact with gold nanoparticles and carbon nanotubes resulting in hybrid materials with intriguing properties. For example, a superhydrophobic composite has been prepared by the interaction of CNT with OPVs. Recently, a composite of the self-assembly with polystyrene prepared through a template polymerization approach has been found to be suitable for thermal imaging (see Figure). The present lecture will highlight various aspects of these soft functional materials.
장 소 : 500동 310호
-Abstract-
The “bottom-up” self-assembly of organic molecules utilizes noncovalent interactions such as hydrogen bonding, -stacking, van der Waals, dipolar and electrostatic interactions. Rational designs of molecular structures that engage in noncovalent interactions are crucial for the creation of nano- to microsized assemblies with controlled shape and size. For the past several years we have been investigating the self–assembly of -conjugated systems such as p-phenylenevinylenes, p-phenyleneethynylenes and thienylenevinylenes. These molecules self-assemble from nonpolar solvents leading to a variety of supramolecular architectures such as tapes, helices, particles and toroids as shown below. At higher concentrations, they form organogels comprising of entangled fibers of nano- to micrometers in size. It has been found that the nature of the conjugated backbone and the attached functional groups play an important role in controlling the morphology of the supramolecular structures. An interesting feature of these self-assemblies is their strong fluorescence which is sensitive to temperature and solvent polarity. In addition, they strongly interact with gold nanoparticles and carbon nanotubes resulting in hybrid materials with intriguing properties. For example, a superhydrophobic composite has been prepared by the interaction of CNT with OPVs. Recently, a composite of the self-assembly with polystyrene prepared through a template polymerization approach has been found to be suitable for thermal imaging (see Figure). The present lecture will highlight various aspects of these soft functional materials.
