• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.349-349
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• 2006

Vinyl-polynorbornene has good thermal stability, high transparency and low dielectric constant. However, it has low solubility, poor mechanical and adhesive properties. In this work, polynorbornene derivatives were prepared by Pd(II) late transition metal catalyst. The polymers have good solubility, and are thermally stable up to$300^{\circ}C$ The glass transition temperature is decreased as the side-chain becomes bulkier. Structure-property relationship of polynorbornene derivatives measured by X-ray scattering, mechanical and electrical properties will be discussed.

• Applied Chemistry for Engineering
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• v.20 no.6
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• pp.612-616
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• 2009

Transparent conductive oxide (TCO) films have been widely used in the field of flat panel display industry. Transparent conductive indium zinc oxide (IZO) thin films with excellent chemical stability have attracted much attention as an alternative material for indium tin oxide (ITO) films. In this study, using a $In_2O_3$ and ZnO powder mixture with a ratio of 90 : 10wt% as a target, IZO films were prepared on polynorbornene (PNB) substrates by electron beam evaporation. The effect of substrate temperature and $O_2$ introduction flow rate were investigated in terms of electrical and optical properties of deposited IZO films. The best electrical and optical properties we obtained from this study were sheet resistance value of $5.446{\times}10^2{\Omega}/{\boxempty}$ and optical transmittance of 87.4% at 550 nm at $O_2$ introduction flow rate of 4 sccm, deposition rate of $2{\AA}$/sec, thickness of 1000 $\AA$ and substrate temperature of $150^{\circ}C$.

• Applied Chemistry for Engineering
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• v.21 no.2
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• pp.224-229
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• 2010

Transparent conductive oxide films have been widely used in the field of flat panel display (FPD). Transparent conductive Indium Zinc Oxide (IZO) thin films with excellent chemical stability have attracted much attention as an alternative material for Indium Tin Oxide (ITO) films. In this study, using $In_2O_3$ and ZnO powder mixture with a ratio of 90 : 10 wt% as a target, IZO films are prepared on polynorbornene (PNB) substrates by electron beam evaporation. The effect of thickness and $O_2$ introduction flow rate on the optical, electrical, structural properties and surface composition of deposited IZO films were investigated by UV/Visible spectrophotometer, 4-point probe method, SEM, XRD and XPS.

• Macromolecular Research
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• v.15 no.2
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• pp.185-190
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• 2007

Poly(norbornene dimethyl dicarboxylate)s, (PNDMD)s, were prepared by addition polymerization with palladium(II) catalyst from pure exo-monomers, and their structure and properties were compared with those of poly(norbornene dicarboxylic acid dialkyl ester)s, (PNDADA)s. Both polymer series exhibited good solubility in general organic solvents and excellent thermal stability up to $330^{\circ}C$. Wide-angle X-ray scattering (WAXS) study indicated the presence of nano-scale layer-like order in amorphous PNDADAs, while PNDMDs showed random amorphous structure. The glass transition temperatures and dielectric constants of solid polymers were found to decrease as the alkyl side-chain length increases for both polymer series. However, PNDMDs showed lower glass transition temperatures and higher dielectric constants, as compared with those of PNDADAs containing the same alkyl substituents. This difference, caused by the higher side-group mobility of PNDMDs, may be closely related to the nano-scale order in amorphous PNDADAs and its absence in PNDMDs.

• Macromolecular Research
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• v.17 no.12
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• pp.995-1002
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• 2009

Luminescent polynorbornene (PNB)/quantum dot (CdSe@ZnS; QD) composite nanorods and nanotubes were successfully prepared using anodic aluminum oxide (AAO) membranes of various pore sizes as templates. To protect QDs with high quantum yield from quenching during the phosphoric acid treatment used to remove the AAO templates, chemically stable and optically clear norbornene-maleic anhydride copolymers (P(NB-r-MA)) were employed as a capping agent for QDs. The amine-terminated QDs reacted with maleic anhydride moieties in P(NB-r-MA) to form PNB-grafted QDs. The chemical- and photo-stability of QDs encapsulated with PNB copolymers were investigated by photoluminescence (PL) spectroscopy. By varying the pore size of the AAO templates from 40 to 380 urn, PNB/QD composite nanorods or nanotubes were obtained with a good dispersion of QDs in the PNB matrix.

• Macromolecular Research
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• v.14 no.1
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• pp.107-113
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• 2006

Processible norbornene copolymers were realized by judiciously designing norbomene comonomers, which were themselves prepared by the Diels-Alder reaction of cyclopentadiene and benzoquinone followed by the isomerization and alkylation of alcohols. The norbornene copolymers containing these derivatized comonomers, prepared by [Pd($x_{2}CH-{3} $)$_{4}$][$SbF_{6}$]$_{2}$ catalyst, exhibited excellent solubility in many organic solvents as well as good thermal stability, as evidenced by their high glass transition ($T_{g}$) and decomposition ($\∼$350$^{circ}C$) temperatures. In addition, fairly strong adhesion to substrates such as glasses and silicon wafers was also achieved with these copolymers to overcome the limitations experienced by polynorbornene homopolymers and to make them attractive for many important industrial applications.

• Journal of the Korean Geosynthetics Society
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• v.22 no.4
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• pp.35-42
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• 2023

This paper described the strength variation characteristics to evaluate the applicability of a reactive material that can absorb organic pollutants as an underground barrier. The Strength was evaluated by unconfined compression test. The test results showed that the strength of the reactive material according to the absorption of each pollutant was in the order of water > TCE > TPH. However, the strength of the reactive material absorbing TPH was greater than that of the case absorbing TCE, when the composition ratio of polynorbornene was 12% or less. The strength of the reaction material in contact with water continued to decrease as the polynorbornene composition ratio decreased. The strength of the reaction material in contact with TCE and TPH increased as the polynorbornene composition ratio decreased from 30% to 21%, and then decreased. In other words, the optimal composition ratio of the reactive material should be applied considering the strength due to contact with pollutants according to the stress conditions occurring in the ground.

• Bulletin of the Korean Chemical Society
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• v.32 no.spc8
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• pp.3074-3080
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• 2011

We synthesized three novel poly(norbornene bisimide)s by ring opening metathesis polymerization (ROMP) and subsequent hydrogenation. Their thermal, mechanical and optical properties were investigated with TGA, DMA, UV-Vis spectrometer, and optical reflectometer. The new polymers showed high glass transition temperatures over $260^{\circ}C$ and good thermal stability with 5% wt-loss temperature higher than $390^{\circ}C$. When solvent casted, they yielded optically transparent and dimensionally stable films with a relatively low coefficient of thermal expansion of about 50 ppm $K^{-1}$. Therefore, the bisimide moieties substantially enhanced thermal and dimensional stabilities, as compared with normal ROMP-prepared polynorbornene films. Though the water uptake was increased to 0.6 wt-%, this water uptake is still considerably lower than that for polyethersulfones (1.4 wt-%) or polyimides (2.0 wt-%). Hence, the new poly(norbornene bisimide)s may become attractive candidates for flexible substrates of optoelectronic devices such as displays and photovoltaic solar cells.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.200-200
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• 2006

Several polynorbornene or poly(norbornene-7-oxide) based functional block copolymers were synthesized by ring opening metathesis polymerization (ROMP) with good molecular weight and polydispersity control. Some representative functional groups in these polymers are a nitrobenzoyl group or ferrocene. These polymers were subjected to various chemical modification reactions to give other block copolymers that contain novel functionality such as amine, diazonium salt, and diazo groups. The resulting polymers were characterized by various techniques such as GPC, NMR, UV-VIS, AFM, and cyclovotammography (CV).

• Bulletin of the Korean Chemical Society
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• v.23 no.7
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• pp.957-963
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• 2002

We successfully synthesized the addition-type polynorbonenes (PNB) exhibiting photochromic properties and excellent thermal stability. Three norbornene-based monomers with different azobenzene moiety (R=NO2, H,OCH3) were synthesized by transesterification method. The corresponding PNB copolymers were synthesized by transition metal-catalyzed addition polymerization method, and characterized by GPC, UV-Vis spectroscopy, NMR, and thermal analysis. For comparison of the photochromic properties depending on the rigidity of polymer backbone, we prepared the polymethylmethacrylate (PMMA) copolymer with the corresponding azobenzene moiety. We investigated the photoisomerization behavior by means of optical muitichannel analyzer with Xe lamp as well as real-time UV-Vis spectroscopy with high-pressure mercury lamp. Among three PNB copolymers, a polymer with azobenzene (R=H) was the most adaptable for observation of photoisomerization behavior. It was found that the rate of photoisomerization and relaxation depended on the structure of azobenzene chromophore, rather than that of polymer backbone.