• Proceedings of the Polymer Society of Korea Conference
• /
• 2006.10a
• /
• pp.9-10
• /
• 2006

Recent work in our laboratory has focused on the molecular and supramolecular engineering of conjugated polymers and oligomers for device applications, including light emitting diodes for displays and lighting, photovoltaic cells, and thin film transistors. A central finding is that the supramolecular structure of conjugated polymers can have a dominant influence on their properties and the performance of devices. Some major results include: highly efficient RGB light-emitting diodes from polymers and oligomers; high mobility n-channel polymer field effect transistors; ambipolar thin film transistors from copolymer semiconductors; and self-assembly and ambipolar charge transport in polymer nanowires.

• Proceedings of the Polymer Society of Korea Conference
• /
• 2006.10a
• /
• pp.19-20
• /
• 2006

We report the design of electroluminescent conjugated polymers for high efficiency, turn-on voltage, color Tuning, and easy processing. Three approaches for the design are reported, being: (1) single chain consideration, (2) supramolecular structure consideration, and (3) conformation manipulation. Two polymer systems are to be reported, being fluorene-based and carbazole-based conjugated polymers.

• Proceedings of the Polymer Society of Korea Conference
• /
• 2006.10a
• /
• pp.248-248
• /
• 2006

The notable feature of the Cu(II) coordination polymer investigated here is its ability to self-assemble into a double-stranded helical structure with regular grooves along the helical axis, through the combination of metal-chloride dimeric interactions and repulsive interactions, as an organizing force. It is also remarkable that the double-stranded helices self-organize into a 2-D columnar structure in both the bulk state and aqueous solution. These results represent a unique example that weak metal-ligand bridging interactions can provide a useful strategy to construct stable double-stranded helical nanotubes.

• Elastomers and Composites
• /
• v.44 no.3
• /
• pp.196-208
• /
• 2009

Sophisticated polymeric materials with 'responsive' properties are beginning to reach the market. The use of reversible, noncovalent interactions is a recurring design principle for responsive materials. Recently developed hydrogen-bonding units allow this design principle to be taken to its extreme. Supramolecular polymers, where hydrogen bonds are the only force keeping the monomers together, form materials whose (mechanical) properties respond strongly to a change in temperature or solvent. In this review, we describe some examples of hydrogen-bonded supramolecular polymers that can be utilized for self-healing materials. Synthesis of a rubber-like material that can be recycled might not seem exciting. But one that can also repeatedly repair itself at room temperature, without adhesives, really stretches the imagination. Autonomic healing materials respond without external intervention to environmental stimuli in a nonlinear and productive fashion, and have great potential for advanced engineering systems.

• Proceedings of the Polymer Society of Korea Conference
• /
• 2006.10a
• /
• pp.309-309
• /
• 2006

Latest developments on hybrid nanostructured materials fabricated by applying self-assembly strategies on organic/inorganic nanotemplates are discussed. Within this frame, numerous functional nanomaterials including arrays of composite metal/semiconductor nanoparticles, planar waveguides and functional multilayer thin films are generated using self-assembled polymers as templates or building blocks. In particular, surface plasmon resonance based optical sensing is employed to investigate nanofabrication processes occurring in nanoscale dimention. We also suggest unprecedented pathways to hybrid supramolecular multilayer nanoarchitectures in 1D or 2D geometry via layer-by-layer self-assembly.

• Bulletin of the Korean Chemical Society
• /
• v.35 no.1
• /
• pp.182-188
• /
• 2014

Three new transition metal complexes based on Ozagrel $[Cu(Ozagrel)]_n$ (1), $[Zn(Ozagrel)(Cl)]_n$ (2), ${[Mn_2-(Ozagrel)(1,4-ndc)_2]{\cdot}(H_2O)}_n$ (3), (Ozagrel = 3-(4-((1H-imidazol-1-yl)methyl)phenyl)acrylic acid; 1,4-ndc = 1,4-Naphthalenedicarboxylic acid) have been hydrothermally synthesized and characterized by elemental analyse, IR, TG, PXRD, electrochemical analysis and single crystal X-ray diffraction. X-ray structure analysis reveals that 1 and 3 are 3D coordination polymers, while complex 2 is a two-dimensional network polymer, the 2D layers are further packed into 3D supramolecular architectures that are connected through hydrogen bonds. The electrochemistry of 1-3 was studied by cyclic voltammetry in methanol and water using a glassy carbon working electrode. Also, thermal decomposition process and powder X-ray diffraction of complexes were investigated.

• Fibers and Polymers
• /
• v.6 no.3
• /
• pp.244-249
• /
• 2005

enVix is a novel regenerated cellulosic fiber, which is prepared from cellulose diacetate fiber using environmentally friendly manufacturing process. Vat dyeing properties of the enVix were investigated and compared with those ofregular viscose rayon. The enVix exhibited better dyeability than viscose rayon. The colour yields of vat dyes on the enVix were found to be dependent on dyeing temperature as well as the amount of levelling agent and salt. Good build-up and good to excellent fastness properties were obtained on the en Vix fabric.

• Fibers and Polymers
• /
• v.5 no.1
• /
• pp.44-51
• /
• 2004

Three bi-functional reactive dyes such as Bis(vinylsulphone) type, Bis(monochlorotriazine) type and Bis(mononicotinotriazine) type were applied to regular viscose rayon and new regenerated cellulosic fiber ($enVix^ⓡ$) which was prepared from cellulose acetate fiber by the hydrolysis of acetyl groups, and their dyeing properties and fastness properties were compared. enVix exhibited better dyeability and fastness than regular viscose rayon and these results were also explained by the differences in the supramolecular structure of these two fibers.

• Fibers and Polymers
• /
• v.5 no.3
• /
• pp.219-224
• /
• 2004

The reactive printing properties of regular viscose rayon and a new regenerated cellulosic fiber (en Vix^{\textregistered}$) which was prepared from cellulose acetate fiber was investigated in a comparative manner. From the results, it was found that en Vix exhibited better printing properties than regular viscose rayon. It showed stable final color yields, irrespective of the amount of thickener, hence reproducibility of printing of en Vix is expected to be excellent. In addition, urea requirements were less for the printings on en Vix than for the corresponding printing on viscose rayon. Therefore, en Vix is also expected to reduce the amount of the urea which causes environmental problems in dyehouse effluent.

• Bulletin of the Korean Chemical Society
• /
• v.33 no.9
• /
• pp.2917-2924
• /
• 2012

Four novel metal-organic complexes $[Cd_2(IP)_2(TBZ)_2(H_2O)_2]{\cdot}(H_2O)$ (1), $[Zn_4(IP)_4(TBZ)_4]{\cdot}2(H_2O)$ (2), $[Zn_2(BTC)(TBZ)_2(CO_2H)]$ (3), [Co(PDC)(TBZ)] (4) (where IP = isophthalate; TBZ = thiabendazole; BTC = 1,3,5-benzenetricarboxylate; PDC = pyridine-3,4-dicarboxylate) have been prepared and characterized by IR spectrum, elemental analysis, thermogravimetric analysis, and single-crystal X-ray diffraction. X-ray structure analysis reveals that 1, 2, and 3 are one-dimensional chain polymers, while 4 is a two-dimensional network polymer. The TBZ acts as a typical chelating ligand coordinated to the metal center in all complexes. The 1D chain architecture of 1 is constructed from isophthalates and cadmium atoms. A simultaneous presence of chelating, monodentate and bidentate coordination modes of IP ligands is observed in complex 2. In complex 3, the 16-membered rings are alternately arranged forming an infinite 1D double-chain structure. The 2D skeleton of 4 is formed by cobalt ions as nodes and PDC dianions as spacers, through coordination bonds. The hydrogen bonds and ${\pi}-{\pi}$ stacking play important roles in affecting the final structure where complexes 1 and 3 have 2D supramolecular networks, while complexes 2 and 4 have 3D supramolecular architectures.