• Korean Chemical Engineering Research
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• v.52 no.2
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• pp.209-213
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• 2014

A graft copolymer of poly(vinyl chloride)-g-poly(oxyethylene methacrylate) (PVC-g-POEM) was synthesized via atom transfer radical polymerization (ATRP) and used as a structure-directing agent to prepare $Al@Fe_2O_3$ core-shell nanocomposites through a sol-gel process. The amphiphilic property of PVC-g-POEM allows for good dispersion of Al particles and leads to specific interaction with iron ethoxide, a precursor of $Fe_2O_3$. Secondary bonding interaction in the sol-gel composites was characterized by Fourier transform-infrared (FT-IR) spectroscopy. The well-organized morphology of $Al@Fe_2O_3$ core-shell nanocomposites was observed using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Energy dispersive X-ray (EDX) and X-ray diffraction (XRD) were used to analyze the elemental composition and crystallization structure of the composites.

• Proceedings of the Korean Fiber Society Conference
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• 1993.06b
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• pp.655-660
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• 1993

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2000.10a
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• pp.5-17
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• 2000

• Proceedings of the Korean Fiber Society Conference
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• 1990.06b
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• pp.70-70
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• 1990

• Membrane Journal
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• v.20 no.1
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• pp.1-7
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• 2010

A graft copolymer, i.e. poly(vinylidene fluoride-co-chlorotrifluoroethylene )-g-poly(styrene sulfonic acid) (P(VDF-co-CTFE)-g-PSSA) with 47 wt% of PSSA was synthesized via atom transfer radical polymerization (ATRP). This copolymer was combined with titanium isopropoxide (TTIP) to produce graft copolymer/$TiO_2$ nanocomposite membranes via sol-gel process. $TiO_2$ precursor (TTIP) was selectively incorporated into the hydrophilic PSSA domains of the graft copolymer and grown to form $TiO_2$ nanoparticles, as confirmed by FT-IR and UV-visible spectroscopy. Water uptake and ion exchange capacity (IEC) decreased with TTIP contents due to the decrease in number of sulfonic acid in the membranes. At 5 wt% of TTIP, the mechanical properties of membranes increased while maintaining the proton conductivity.

• Elastomers and Composites
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• v.48 no.1
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• pp.30-38
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• 2013

Polyolefin is one of the most important commodity polymers having excellent physical properties and cost competitiveness, which has continuously broadened their market in response to a heavy demand from industry. However, the lack of polarity in polyolefin has limited its applications, especially where interactions with other materials are important. In view of the above, the incorporation of polar functional groups in polyolefin has been widely attempted. Especially, the preparations of segmented modified polyolefin copolymers, such as block and graft copolymers have been extensively investigated, since the loss of the original properties of polyolefin can be minimized while the polar segments can endow interactions with other materials. Living radical polymerization (LRP) method can be one of the most attractive synthetic tools for the preparation of the modified polyolefin block or graft copolymers. In this review, progress on the preparation of the polyolefin based block or graft copolymers through LRP technique is briefly summarized.

• Elastomers and Composites
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• v.14 no.1
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• pp.7-12
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• 1979

Graft copolymerization of methlymethacrylate(MMA) onto sodium alginate(SA) aqueous solution by sodium metaperiodate$(NaIO_4)$ as an initiator was carried out with the variation of the reaction time, the reaction temperature and the concentrations of initiator and monomer. The results obtained were as follows: 1. SA was easily separated from the reaction mixture of homopolymer, graft polymer and sodium alginate ungrafted by the treatment of concentrated boiling $Na_3PO_4$, solution with the small amount of $Na_2SO_3$ to the mixture and then isolated as the acid form by acidifying the salts solution containing SA. 2. The amount of graft polymer was larger than that of homopolymer below $70^{\circ}C$ whereas above $70^{\circ}C$ the amount of homopolymer was larger. 3. The sum of each amount of graft polymer ana homopolymer was always increased with increase of the reaction time, the reaction temperature and the concentrations of initiator and monomer. 4. With increase of the concentration of initiator, the graft efficiency was increased below $70^{\circ}C$ while decreased above $70^{\circ}C$. 5. Graft copolymerization of MMA onto SA in aqueous solution was carried out without initiator.

• Polymer(Korea)
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• v.34 no.2
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• pp.126-132
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• 2010

A cation-exchange nanofiber poly(vinylidene fluoride) (PVdF) membrane was prepared by a radiation-induced graft polymerization (RIGP) of sodium styrene sulfonate (NaSS) in the presence of the polymerizable access agents in methanol solution. The used polymerizable access agents include styrene, acrylic acid, and vinyl pyrrolidone. The anion-exchange nanofiber PVdF membrane was also prepared by RIGP of glycidyl methacrylate (GMA) and its subsequent chemical modification. The successful preparations of cation- and anion-exchange PVdF membranes were confirmed via SEM, XPS and thermal analysis. The content of the grafting yield, ion-exchange group, and water uptake was in the range of 30.0~32.3%, 2.81~3.01 mmol/g and 66.6~147%, respectively. The proton conductivity at 20$^{\circ}C$ was in the range of 0.020~0.053 S/cm. From the result, the prepared ionexchange PVdF membrane can be used as a separator in battery cells.

• Polymer(Korea)
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• v.35 no.3
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• pp.216-222
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• 2011

A multi-walled carbon nanotube (MWNT) support with dual properties, an ionic property via tetra-amine and unpaired electrons via tri-amine, was prepared by radiation-induced graft polymerization of glycidyl methacrylate (GMA) and the subsequent amination of its epoxy group. The electrochemical microbial biosensor (EMB) was then fabricated by immobilization of a microbe (Alkaligenes spp.) onto the dual property-modified electrode, which was prepared with the mixture of the MWNT support and a $Nafion^{(R)}$ solution on a glass carbon (GC) electrode surface by a hand-casting method. The sensing range of the prepared EMB for phenol in a phosphate buffer solution was 0.005~7.0 mM. The total concentration of phenolic compounds in a commercial red wine was also determined using the EMB.

• Textile Coloration and Finishing
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• v.6 no.2
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• pp.17-23
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• 1994

Carboxylic acid group gradient surface where the density of carboxylic acid groups changes gradually along the sample length was prepared. Carboxylic acid group gradient surface was produced by the treatment of low density polyethylene sheet using a corona with gradually increasing power, followed by the grad polymerization of acrylic acid. The prepared gradient surface was characterized by the measurement of water contact angle, Fourier-transform infrared spectroscopy in the attenuated total reflectance mode, and electron spectroscopy for chemical analysis.