• 한국염색가공학회지
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• 제10권6호
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• pp.49-54
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• 1998

The antimicrobial activities of the copolymer of N,N'-dimethyl-N,N'-diallyl ammonium chloride (DMDAAC) and acrylamide(AA) were investigated. A series of copolymers with various ratios of DMDAAC and AA were prepared by free radical initiation via an intra-intermolecular propagation mechanism, ie, cyclopolymerization, and the antimicrobial activities of the prepared copolymers were measured by minimum inhibitory concentration(MIC) test. The copolymers were, then, methylolated under basic condition for reactivity with hydroxyl group of cellulose. Both antimicrobial activity and fastness to laundering of the cotton fabrics finished using the methylolated copolymers were evaluated. From the results it was shown that the copolymers with different ratios of DMDAAC and AA have MIC values in the range of 1∼100ppm. As the ratio of AA in the copolymers increases, the anitmicrobial activity decreases. The fastness of the cotton fabric finished by the methyolated copolymers to 10 repeated launderings in anionic commercial detergent is good enough to show colony reduction above 90％ regardless of DMDAAC and AA ratios.

• 폴리머
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• 제34권4호
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• pp.306-312
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• 2010

Triphenylvinylsilane (TPVS) containing vinyl acetate (VAc), butyl acrylate (BA), and Nmethylolacrylamide (NMA) copolymers were prepared by emulsion polymerization. The polymerization was performed at $80^{\circ}C$ in the presence of auxiliary agents and ammonium peroxodisulfate (APS) as the initiator. Sodium dodecyl sulphate (SDS) and Arkupal N-300 were used as anionic and nonionic emulsifiers, respectively. The resulting copolymers were characterized by using Fourier transform infrared spectroscopy (FTIR), gel permeation chromatography (GPC), and dynamic light scattering (DLS). Thermal properties of the copolymers were studied by using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The morphology of copolymers was also investigated by scanning electron microscopy (SEM) and then the effects of silicone concentrations on the properties of the TPVS-containing VAc-acrylic emulsion copolymers were discussed. The obtained copolymers have high solid content (50%) and can be used in weather resistant emulsion paints as a binder.

• 펄프종이기술
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• 제44권2호
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• pp.8-17
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• 2012

Three kinds of cationic acrylamide copolymer with different branch degree were prepared controlling the dosage of N, N'-methylenebisacrylamide. The physical characteristics of the branch-degree-modified copolymers were analyzed by intrinsic viscosity and charge density. The branch degree measurements were investigated by applying the colloidal titration phenomena using a spectrophotometer and comparison with the cationic regain measurement method. The results showed that the absorbance behaviors of spectrophotometer were distinctively different with the branch degree of copolymers. Also, the branch degree determinations and molecular structure estimations of the copolymers were numerically measured by applying the titration phenomena using a spectrophotometer. Finally, three kinds of branch-degree-modified copolymers were applied to flocculation test using arbocel micro pulp for the determination of flocculation behavior by different morphology of cationic acrylamide copolymers.

• Fibers and Polymers
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• 제4권4호
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• pp.156-160
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• 2003

Poly(ethylene 2,6-naphthalate) (PEN)/Poly(ethylene glycol) (PEG) copolymers were synthesized by two step reaction during the melt copolymerization process. The first step was the esterification reaction of dimethyl-2,6-naphthalenedicarbox-ylate (2,6-NDC) and ethylene glycol (EG). The second step was the condensation polymerization of bishydroxyethylnaphthalate (BHEN) and PEG. The copolymers contained 10 mol% of PEG units with different molecular weights. Structures and thermal properties of the copolymers were studied by using $^1{H-NMR}$, DSC, TGA, etc. Especially, while the intrinsic viscosities of PEN/PEG copolymers increased with increasing molecular weights of PEG, but the glass transition temperature, the cold crystallization temperature, and the weight loss temperature of the copolymers decreased with increasing molecular weights of PEG. Consequently, the hydrophilicities by means of contact angle measurement and moisture content of the copolymer films were found to be significantly improved with increasing molecular weights of PEG.

• Macromolecular Research
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• 제16권7호
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• pp.609-613
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• 2008

Poly($\varepsilon$-caprolactone)-poly(ethylene glycol)-poly($\varepsilon$-caprolactone) (PCL-PEG-PCL) multiblock copolymers at various hydrophobic-hydrophilic ratios were successfully synthesized by the chain extension of triblock copolymers through isocyanate (hexamethylene diisocyanate). Biodegradable films were prepared from the resulting multiblock copolymers using the casting method. The mechanical properties of the films were improved by chain extension of the triblock copolymers, whereas the films prepared by the triblock copolymers were weak and brittle. Atomic force microscopy (AFM) of the multiblock copolymer film showed that the hydrophilic PEG had segregated on the film surface. This is consistent with the observed contact angle of the films.

• 대한화학회지
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• 제14권1호
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• pp.29-35
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• 1970

Chacterization of MMA/AN organosol copolymer and subsequent comparison with the prior art latex copolymers has been accomplished. By means of NMR analyses, we found both types of copolymers to be random. The GPC analyses show that the organosol copolymers have a singnificantly broader MW spread than latex copolymers. This is due to the low MW stabilizer which is present as a physical mixture. As a result, the MW distribution is bimodal. Fractionation of a typical organosol copolymer yields a low MW(33,000-100,000), MMA rich fraction and a high MW (250,000-330,000), AN rich fraction. Solubility-wise, the organosol copolymers are readily soluble in the lacquer solvent MEK to give a colorless film. The prio rart copolymers, hewever, were imcompletely soluble and gave yellow, hazy film.

• Macromolecular Research
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• 제13권4호
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• pp.297-305
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• 2005

The compatibilizing effect of maleic anhydride (MA) in the immiscible blends of EVA22 (vinyl acetate content 22%)/ethylene-${\alpha}$-olefin copolymers with 1-butene (EtBC) and 1-octene (EtOC)) comonomers was studied. By adding 1, 2, and 3 phr of MA in the presence of dicumylperoxide, the morphology, tensile strength at break, and 100 and 300 % modulus of EVA22/EtBC and EVA22/EtOC blends were significantly enhanced. The melting point and crystallization point depression were observed upon the addition of MA. The changes in the ${\beta}$ transition and glass transition temperature of ethylene-${\alpha}$-olefin copolymers and ethylene-vinyl acetate copolymers, respectively, indicate that MA plays a role of compatibilizer for these immiscible blends. The TGA thermograms, measured from the blends with MA, show that thermal stability is slightly enhanced with MA, indicating that MA acts as a reinforcing agent either by grafting or crosslinking with other copolymers.

• Macromolecular Research
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• 제11권2호
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• pp.115-121
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• 2003

In this research, the in vitro anti-thrombogenecity of artificial materials was evaluated using hydrophilic/hydrophobic copolymers containing oiligosaccharide as hydrophilic moiety and phospholipid as hydrophobic moiety respectively. N-(p-vinylbenzyl)-[O-$\alpha$-D-glucopyranosyl-(1longrightarrow4)]$_{n-1}$-D-glucoamide(VM7A) was (VM7 A) was adopted as hydrophilic oligosaccharide and 2-acryloxybutyl-2-(triethylammonium)ethyl phosphoric acid (HBA-choline) was adopted as hydrophobic phospholipid. Copolymers having various monomer feeding molar ratios were synthesized through radical polymerization. The synthesized copolymers were identified using FT-IR, $^1$H-NMR, XPS, and DSC. The surface energy of the copolymers were evaluated by dynamic contact angle (DCA) method and checked different roles of VM7A as hydrophilic moiety and HBA-choline as hydrophobic moiety on surface. The surface morphological differences between hydrated and unhydrated surfaces of copolymers were observed and evaluated using Am. The platelets were separated from canine whole blood by centrifugation and adopted to the anti-thromobogenecity test of the copolymers. From the results, we find out that as VM7A ratio increases, so did anti-thrombogenecity. Such results show the possibility of using these copolymers as blood compatible materials in living body.y.

• Macromolecular Research
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• 제12권4호
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• pp.342-351
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• 2004

Poly(ethylene glycol) (PEG1K) and sulfonated PEG (PEG1K-SO$_3$) methacrylate (MA) copolymers have been prepared and characterized. The structures of the synthesized copolymers were confirmed by $^1$H and $^{13}$ C NMR spectroscopy and elemental analysis. The bulk characteristics of the copolymers were evaluated by viscosity and thermal analysis. The surface properties of the copolymers were investigated using dynamic contact angle measurements and electron spectroscopy for chemical analysis. The hydrophilicity of the surfaces modified with PEG1KMA or PEG1K-SO$_3$MA increased, possibly as a result of the orientation of the hydrophilic PEG1KMA/PEG1K-SO$_3$MA chains into the water phase. Platelets adhered less to the surfaces of the copolymers than they did to a polyurethane control. In addition, adhesion of platelets to the copolymer surfaces decreased upon increasing the chain density of PEG1KMA and sulfonated PEG1KMA in the copolymers. Both bacterial adhesion and protein adsorption were significantly reduced on the copolymer surfaces and their levels differ depending on the kind of surface or media.

• Bulletin of the Korean Chemical Society
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• 제19권11호
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• pp.1179-1184
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• 1998

Mesogenic and azo monomers were synthesized and copolymerized to obtain two copolymers composed of methacrylate and itaconate backbone. Glass transition temperatures of the copolymers were found to be slightly higher than ambient temperature. Both the copolymers showed liquid crystalline properties. Trans-cis isomerization in film state was observed under UV-irradiation with a light of 365 nm. Regarding the photochemical phase transition behavior, the transition rate of nematic-to-isotropic state was slightly faster in the methacrylate copolymer during irradiation at 365 nm and the rate of the reverse transition was much faster in itaconate copolymer under thermal effect.