• Bulletin of the Korean Chemical Society
• /
• v.17 no.5
• /
• pp.443-447
• /
• 1996

Several polysilanes with sterically bulky substituents such as poly(2-phenylpropyl)(n-hexyl)silane were prepared by Wurtz-type coupling. The polysilane products were mixtures of low-molecular-weight polymers (&bar{M};w~103) as major and high-molecular-weight polymers (&bar{M};w~106) as minor. Overall yields for polysilanes were in the range of 81-99%. λmax of liquid low MW polymers appeared at around 280 nm. Formations of solid high MW polymers were decreased by a longer reaction time and increased steric bulkiness of substituents. High MW polymers with λmax at 327 nm except crosslinked polymers were soluble in common organic solvents and found to be light sensitive. Crosslinked high MW polymer gave 21% TGA ceramic yield, compared with linear high polymer giving zero ceramic yield.

• Proceedings of the Korean Society of Potoscience Conference
• /
• 2006.06a
• /
• pp.72-72
• /
• 2006

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.22 no.2
• /
• pp.163-168
• /
• 2009

Hyperbranched conjugated polymers (p-HPPV and m-HPPV) with para and meta linkages were synthesized from $A_2$ and $B_4$ type monomers through Wittig polycondensation. The synthesized p-HPPV and m-HPPV were completely soluble in common organic solvents such as chloroform, tetrahydrofuran, 1,2-dichloroethane, etc. and thermal gravimetric analyses showed that p-HPPV and m-HPPV are stable up to $350^{\circ}C$. The molecular weights (from GPC), UV-visible, and photoluminescence maximum peaks of p-HPPV and m-HPPV are characterized in detail. The fabricated EL devices using the synthesized hyperbranched polymers, (ITO/(p-HPPV or m-HPPV)/Al), showed EL emission at about 507 nm and 481 nm (681 nm), respectively. Especially, EL device from m-HPPV were found to exhibit nearly white emission with approximate CIE coordinates of (0.31, 0.34) compared with (0.310, 0.316) of NTSC white color at $100\;cd/m^2$. The good photophysical properties combine with good film-form ability could make these hyperbranched polymers to be a potential candidate for the EL materials.

• Fibers and Polymers
• /
• v.2 no.2
• /
• pp.92-97
• /
• 2001

New film forming aromatic poly(amide-imide)s containing isoindoloquinazolinedione (IQ) unit in the backbone chain (polymer XIV) have been successfully synthesized by preparing prepolymers of poly(amic acid-carbonamide). followed by subsequent thermal cyclization of the prepolymers. 4,4-Diamino-3-carbamoylbenzanilide (DACB) V has been synthesized by reduction of 3-carbamoyl-4-amino-4-nitrobenzanilide IV. The prepolymers of poly(amic-acid-carbonamide) (polymers VII and VIII) which exhibit viscosities ranging from 1.4 to 1.7 dl/g have been prepared by a condensation polymerization of monomers such as BPDA, ODA, and DACB. Polymer XIV has been obtained by thermal cyclization of the polymers VII and VIII. During the thermal cyclization reaction, imide ring structure was first introduced and then transformed to the structure of IQ unit. The thermal degradation rate of the resultant polymers were influenced by the cleavage of amide bond but the final char yield was comparable to that of poly(BPDA-ODA).

• Macromolecular Research
• /
• v.16 no.3
• /
• pp.261-266
• /
• 2008

A variety of end-functionalized polymers were grafted spontaneously onto multi-walled carbon nano-tubes (MWNTs) using a solution mixing process. The end-functional groups of the polymers underwent noncovalent grafting to the defect sites at the surface of the purified MWNTs through zwitterionic interaction or hydrogen bonding. The physically grafted polymers including polystyrene (PS), poly(methyl methacrylate) (PMMA), polyethylene oxide (PEO), and polydimethylsiloxane (PDMS) provided sufficient compatibility with an organic solvent or polymer matrix, such that the nanotubes could be finely dispersed in various organic media. This approach is universally applicable to a broad range of polymer-solvent pairs, ensuring highly dispersed carbon nanotubes through simple solution mixing.

• Journal of the Korean Electrochemical Society
• /
• v.13 no.1
• /
• pp.57-62
• /
• 2010

New monomers, possessing various alkyl substituents on propylene dioxypyrrole, were synthesized. The monomers could be easily polymerized to produce highly conductive and soluble polymers. The corresponding polymers showed excellent solubility, retaining electrochemical and optical properties of their parent polymer [poly(propylene dioxypyrrole)]. The conductivities of chemically prepared polymers were quite high in a range of 20 and $60\;Scm^{-1}$. Solubility of the polymer in a common organic solvent was as high as no polymer is deposited on an electrode. The redox potentials of the electrochemically prepared polymers revealed quite stable electro-activity during repeated redox switching up to 500 times. The optoelectrochemistry studies also showed distinct color changes of the polymers upon changing the doping state, indicating strong absorption peaks at 400~600 nm in reduced states and complete bleaching in fully oxidized states.

• Macromolecular Research
• /
• v.11 no.6
• /
• pp.501-505
• /
• 2003

Poly(l,6-heptadiyne) derivatives with phenoxy and 3,7-dimethyloctyloxyphenoxy substituents were synthesized using metathesis polymerization. Polymerizations using MoCl$\sub$5/ as the sole catalyst gave high yields and the resulting polymers were completely soluble in organic solvents. The polymers' structures and thermal properties were characterized using NMR and UV-Vis spectroscopy, as well as with TGA and DSC thermograms. From the analysis of the high-resolution $\^$13/C-NMR spectra, we was found that these polymers contain six-membered rings. The number-average molecular weights and polydispersities of the polymers were ca. 7.0∼20 ${\times}$ 10$^3$ and 3.1∼5.8, respectively. The glass transition temperatures of the polymers were found to be in the range 91∼159$^{\circ}C$.

• Macromolecular Research
• /
• v.8 no.5
• /
• pp.209-214
• /
• 2000

Polyenaminonitriles containing cycloaliphatic and aliphatic units were prepared by interfacial or solution polymerization reaction of p-bis(1-chloro-2,2-dicyanovinyl) benzene (1) with 4-aminobenzyl-amine, 1-(2-aminoethyl)piperazine, 2-(aminomethyl)pyrrolidine and 4-(aminomethyl)piperidine. The chemical structure of the polymers was confirmed through a syntheses of the model compound. The resulting polymers possessed inherent viscosities of 0.29∼0.62 dL/g and they were easily soluble in polar aprotic solvents and common organic solvents. Thermal properties of the polymers such as curability and stability were studied by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and infrared spectroscopy. The polymers exhibited a large exotherm in DSC analyses and underwent a curing reaction around 340-370$\^{C}$ to form insoluble materials. The polymers showed 70-80% residual weight at 600 $\^{C}$ under nitrogen.

• Bulletin of the Korean Chemical Society
• /
• v.30 no.10
• /
• pp.2371-2376
• /
• 2009

Three phenoxazine-based conjugated polymers, namely, the aryl substituted phenoxazine homopolymer (P1) as well as the dimeric phenoxazine-fluorene (P2) and phenoxazine-bithiophene (P3) copolymers, were synthesized via the Ni(0) mediated Yamamoto reaction and the palladium-catalyzed Suzuki coupling reaction. The weight-averaged molecular weights ($M_w$) of P1, P2, and P3 were found to be 27,000, 22,000, and 15,000, respectively, and their polydispersity indices were 3.6, 1.8, and 2.1. All the polymers were soluble in common organic solvents such as chloroform, toluene, and so on. The UV-visible absorption maxima for P1, P2, and P3 in the film state were located at 421, 415 and 426 nm, respectively, and the ionization potentials of the polymers ranged between 4.90 and 5.12 eV. All the studied phenoxazine-based polymers exhibited amorphous behavior, as confirmed by X-ray diffraction (XRD) and atomic force microscopy (AFM) studies. Thin film transistors were fabricated using the top-contact geometry. P1 showed much better thin-film-transistor performance than P2 or P3: A thin film of P1 gave a saturation mobility of 0.81 ${\times}\;10^{-3}\;cm^2V^{-1}s^{-1}$ and an on/off ratio of about $10^2$.

• Journal of the Korean institute of surface engineering
• /
• v.12 no.3
• /
• pp.174-179
• /
• 1979

The effects of brightness, electrochemical behaviour on the organic additives, such as aldehydes, polymers, amines and condensed product obtained from epichlorohydrin and nicotinamide, in cyanide zinc electrolplating bath have been studied by controlled potential electrolyser. The results were summerized as follows: (1) It was found that the addition of only one compound of these organic compounds in the bath was unsuitable but mixture of anisaldehyde or monoethanolamine and condensed product as suitable as brightener. (2) The cathodic polarization curve of polymers or aldehydes in cyanide zinc electroplating bath was almost the same but the cathodic polarization curve of condensed product remarkable shifted to noble potential more than non-additive curve.