• Bulletin of the Korean Chemical Society
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• v.23 no.4
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• pp.633-636
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• 2002

• Applied Chemistry for Engineering
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• v.7 no.2
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• pp.289-298
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• 1996

Eight kinds of poly(oxyethylene, oxyisopropylene) dodecyl ethers were synthesized by adding ethylene oxide and isopropylene oxide with each 5 and 10 moles alternatively on dodecanol. The addition of EO and PO for eight kinds of sodium poly(oxyethylene, oxyisopropylene) dodecyl ether sulfates was identified with HPLC, $^1H$ NMR, hydroxy value, and IR spectrum. In order to verify the sulfation the number of EO and PO molecules was obtained by spectra and Epton method. The yields of products sulfated by chlorosulfonic acid were 90~96%.

• Clean Technology
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• v.17 no.3
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• pp.244-249
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• 2011

We synthesized low molecular-weight polymers bearing hydrophobic and hydrophilic parts in a chain through $CO_2$/propylene oxide copolymerization. When hydrophilic poly (ethylene glycol) bearing -OH group (s) at the end group (s) was added as a chain transfer agent in the $CO_2$/propylene oxide copolymerization catalyzed by a highly active catalyst, block polymers were formed. If poly (ethylene glycol) (PEG) bearing -OH group only at an end was fed, PEG-block-PPC diblock copolymer was obtained. When PEG bearing -OH group at both ends was fed, PPC-block-PEG-block-PPC triblock copolymer was obtained. We confirmed formation of block copolymers by $^1H$-NMR spectroscopy and GPC studies.

• Applied Chemistry for Engineering
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• v.20 no.5
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• pp.527-531
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• 2009

Periodic mesoporous organosilicas (PMO) were synthesized using bis(triethoxy silyl) benzene as the precursor and dodecyl trimethyl ammonium bromide (DTMA) as the templating agent. From these results of XRD, TEM, and NMR, the pore structure of the material was confirmed to have a well-organized hexagonal structure. Poly(ethylene oxide) (PEO) was penetrated into PMO. From the DSC and XRD experiments, the polymer melting transition of crystalline polyethylene oxide (PEO) decreased then finally disappeared. These results prove that the polymer chains penetrate into the PMO channels, and penetrated polymer chains are constrained inside channels of PMO.

• Polymer(Korea)
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• v.25 no.6
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• pp.759-764
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• 2001

In order to obtain PEO with reduced crystallinity, novel PEO derivatives containing carbonate linkages in the main chain have been synthesized by the reaction of various molecular weight poly (ethylene glycol)s (PEGs) with dimethyl carbonate (DMC) in the presence of $H_2SO_4$ to yield methyl carbonate terminated PEGs, followed by condensation reaction under vacuum in the presence of titanium isopropoxide (TiP) catalyst. The number average molecular weight of PEGs used was in the range of 200 and 600 g/mol. The structure and compositions of the resulting polymers were characterized by $^1$H-NMR and $^{13}C-NMR$. Their thermal behavior and molecular weight were characterized by DSC/TGA and GPC, respectively.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.55.1-55.1
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• 2011

Dye-sensitized solar cell(DSSC) have been considered one of the promising alternatives to conventional solar cells, because of their low cost, easy fabrication and relatively high energy conversion efficiency. However, although the cell offers reasonable efficiency at least 11%, the use of a liquid electrolyte placed technological challenges for achieving the desired durability and operational stability of the cell. In order to prevent or reduce electrolyte leakage considerable efforts have been made, such as p-type semiconductor or organic hole-transport material that better mechanical properties and simple fabrication processes. In this work, we synthesized solid-state electrolyte containing LiI and KI metal salt with starting materials of poly ethylene oxide to substitute liquid electrolyte enhance the ionic conductivity and solar conversion efficiency. Li+ leads to faster diffusion and higher efficiency and K+ leading to higher ionic conductivity. The efficiency of poly ethylene oxide/LiI system electrolyte is 1.47% and poly ethylene oxide/potassium electrolyte is 1.21%. An efficiency of 3.24% is achieved using solid-state electrolyte containing LiI and KI concentrations. The increased solar conversion efficiency is attributed to decreased crystallinity in the polymer that leads to enhanced charge transfer.

• Macromolecular Research
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• v.10 no.1
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• pp.49-52
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• 2002

Rod-coil amphiphilic block copolymers, PALG-PEOs, poly(alkyl $\alpha$, L-glutamate-co-ethylene oxide)s, were successfully synthesized in three steps: 1) esterification of L-glutamic acid, 2) synthesis of ${\gamma}$-alkyl L-gultamate N-carboxyanhydride, and 3) polymerization of NCA monomers. These molecules form polymeric micelles with the hydrophobic core and hydrophilic corona in aqueous solution, which were characterized by light scattering and static fluorescence measurement.

• Proceedings of the KOSOMBE Conference
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• v.1996 no.11
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• pp.327-330
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• 1996

Poly(L-leucine)(PLL)/poly(ethylene oxide)(PEO)/poly (L-leucine)(PLL) block copolymers were synthsized by polymerization of L-leucine N-carboxyanhydride with diamine-terminated PEO for possibility of wound dressing which may have several advantages such as 1) increase of solubility, 2) control of biodegradation, 3) absorption of body fluid. 4) non-immunogenic effect than PLL homopolymer wound dressing aleady commercialized. Water content increased with an increase of PEO content in the block copolymer due to the hydrophilicity of PEO. Release of silver sulfadiazine(AgSD) from AgSD loaded wound dressing increased with an increase of PEO content in the block copolymer. It was found that the number of Pseudomonas aeruginosa decrease with an increase of PEO content due to the fast release of antibacterial agents with an increase of PEO content in the block copolymer.

• Proceedings of the Korean Fiber Society Conference
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• 1991.06a
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• pp.29-29
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• 1991

• Bulletin of the Korean Chemical Society
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• v.15 no.9
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• pp.748-751
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• 1994

Poly(ethylene oxide) (PEO) in aqueous solutions has a hydrophobic character which can induce the hydrophobic interaction between its nonpolar parts. The hydrophobic properties of aqueous PEO solutions are studied by the viscometry in terms of the water structure-making and -breaking capabilities of added solutes of ureas. The results show that the contracted conformation of PEO of low molecular weight, namely poly(ethylene glycol) (PEG), does not result from the hydrophobic interaction between the nonpolar parts of PEO but it can participate in a hydrophobic interaction between the nonpolar parts of PEO and added ureas solutes with nonpolar groups, which can induce a large hydrodynamic volume and increase the viscosity. On the other hand, the PEO of large molecular weight seems to behave like any other water soluble polymers with nonpolar parts and its conformation in aqueous solutions is well explained in terms of water structure perturbing capabilities of added ureas.