• Journal of the Korean Chemical Society
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• v.21 no.4
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• pp.284-292
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• 1977

Epoxy-methacrylate prepolymer was synthesized from methacrylic acid and a diglycidyl ether type low molecular weight epoxy resin, and the electron beam curing of the prepolymer was studied using styrene and polyethyleneglycol dimethacrylates as comonomers. The esterification was carried out quantitatively without any side reaction adding more than 250∼300ppm hydroquinone and less than $1{\%}$ (wt) triethanolamine by wt. of methacrylate acid, respectively. In the radiation curing under air atmosphere, the maximum gel fraction was observed at 10∼$30{\%}$ monomer contents. The rate of gel formation was decreased by the presence of unreacted epoxy group and acid in the prepolymer and increased with increasing degree of polymerization of polyethyleneglycol block in the dimethacrylates. Considerable oxygen effect in the curing, particularly when polyethyleneglycol dimethacrylate was used as a comonomer, was recognized through the differences of the product properties, though no remarkable differences were found in the rate of gel formation in air and nitrogen atmosphere.

• Advances in materials Research
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• v.2 no.1
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• pp.15-36
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• 2013

Incorporation of polar functional moieties into polyethylene (PE) film has been achieved by graft copolymerization of polar monomers such as methacrylic acid (MAAc) and acrylamide (AAm) on to PE film, preirradiated with ${\gamma}$-rays from $^{60}Co$ source, using benzoyl peroxide (BPO) as initiator in aqueous medium. Percentage of grafting of MAAc and AAm was determined as a function of irradiation dose, monomer and initiator concentration, temperature, reaction time and amount of water. Maximum percentage of grafting of MAAc (1453%) and AAm (21.28%) was obtained at [MAAc] = $235.3{\times}10^{-2}$ mol/L, [AAm] = $23.4{\times}10^{-2}$ mol/L, [BPO] = $5.5{\times}10^{-2}$ mol/L and $16.5{\times}10^{-2}$ mol/L at $80^{\circ}C$, $90^{\circ}C$ in 180 min and 90 min respectively. The grafted PE films were characterized by FTIR, Thermogravimetric analysis (TGA) Scanning Electron Micrography (SEM) and X-ray diffraction methods. Some selective properties of grafted films such as swelling behavior, ion and metal uptake have been carried out. The biodegradation studies of the grafted PE films have also been investigated. The grafted films developed superior swelling behavior with maximum swelling (480%) in water as compared to pristine PE (13.55%), better thermal stability and ion and metal uptake studies showed promising results that can be effectively used for desalination of brackish water and separation of metals from the industrial effluents.

• Journal of Pharmaceutical Investigation
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• v.2 no.1
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• pp.40-51
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• 1972

Water vapor sorption of corn starch in various protective film coated capsules in 100% RH chamber for 14 days were as follows: The percent of water vapor sorption were 28.63% in uncoated capsule, 25.16% in hydroxy propylcellulose(HPC) coated capsule, 15.59% in 2-methyl-5-vinyl pyridine-methyl acrylated-methacrylic acid (MPM) coated capsule and 15.50% in polyvinyl acetal diethyl amino acetate(AEA) coated capsule. 2. Water vapor sorotion of magnesium trisilicate in various protective film coated capsules in 100% RH chamber for 14 days were as follows. The percent of water vapor sorption were 13.91% in uncoated capsule, 13.30% in HPC-coated capsule, 10.87% in MPM-caated capsule and 9.9% in AEA-coated capsule. 3. Water vapor sorption of magnesium carbonate in various protective film coated capsules in 100% RH chamber for 14 days were as follows: The percent of water vapor sorption were 12.48% in uncoated capsule, 10.72% in HPC-coated capsule, 8.10% in MPM coated capsule and 7.8% in AEA-coated capsule. 4. MPM-coated capsules and AEA-canted capsules were mere effective to protect water vapor sorption than HPC-coated capsules.

• Elastomers and Composites
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• v.31 no.5
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• pp.341-346
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• 1996

The fracture mechanics investigation of the thermoplastic vulcanizates(TPV) from EPDM and PP/Ionomer ternary blends was performed in terms of the J-integral by measuring fracture energy via the locus method. The TPV from ternary blends consisting of EPDM, PP and ionomer were prepared in a laboratory integral mixer by blending and vulcanizing simultaneously. Vulcanization was performed with dicumyl peroxide (DCP) and the composition of EPDM and PP was fixed at 50/50 by weight. Two kinds of poly(ethylene-co-methacrylic acid) (EMA) lonomers were used. The J-integral values at crack initiation, Jc, of the dynamically vulcanized EPDM and PP/EMA Ionomer ternary blends were affected by the cation types $(Na^+\;or\;Zn^{2+})$ and contents(5-20wt%) of the added EMA Ionomers. The ternary blend containing 20wt% zinc-neutralized EMA Ionomer and 1.0phr DCP showed the highest Jc values of the blends.

• Polymer(Korea)
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• v.37 no.3
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• pp.288-293
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• 2013

A group of molecularly imprinted polymers (MIPs) with specific recognition for chiral (S)-ibuprofen were successfully prepared based on hydrogen bonds, utilizing ${\alpha}$-methacrylic acid as a functional monomer. The IR analysis of MIPs showed that the blue- and red-shifted hydrogen bonds were formed between templates and functional monomers in the process of self-assembly imprinting and re-recognition, respectively. According to UV-Vis analysis, we found that the ratio of host-guest complexes between template molecule and functional monomer was 1:1. The effect of cross-linker's quantity on the polymerization was studied by transmission electron microscope (TEM). The adsorption selectivity experiments indicated that MIPs exhibited higher selectivity to (S)-ibuprofen than those to ketoprofen and (R)-ibuprofen, (S)-ibuprofen's structural analogs.

• Journal of the Korean Ceramic Society
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• v.41 no.5
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• pp.417-424
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• 2004

Polycarboxylate type superplasticizers (PCA) with different graft chain (Polyethylene oxide) length were synthesized by Methoxypoly (ethyleneglycol)monomethacrylate (MPEGMAA) and methacrylic acid (MAA). The effects of PCA on the hydration of Ordinary Portland Cement (OPC) were investigated by Fourier Transform Infrared Spectroscopy (FT-IR), X-Ray Diffraction (XRD) and Differential Scanning Calorimetry (DSC) techniques. The effect of graft chain length of PCA on the hydration of OPC was different at early age, but, at long age, was similar. The ratio of relative peak intensity, (I［001］/I［101］), of Ca(OH)$_2$ compared with OPC also was reduced by PCA addition.

• Bulletin of the Korean Chemical Society
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• v.35 no.7
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• pp.2033-2037
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• 2014

A reaction mixture was developed for formation of soft organic monolith that was easily smashed, rinsed, refluxed, filtered, and dried to give monolith particles having high pore volume of macropores. This phase was almost without mesopores. The reaction mixture was composed of methacrylic acid, ethylene glycol dimethacrylate, polyethylene glycol (porogen), and an initiator in a mixed solvent of toluene and isooctane. The selection of porogen and its amount was carefully carried out to obtain the optimized separation efficiency of the resultant phase. The median macropore size was 1.6 ${\mu}m$, and the total pore volume was 3.0-3.4 mL/g. The median particle size (volume based) was 15 ${\mu}m$, and the range of particle size distribution was very broad. Nevertheless the column (1 ${\times}$ 300 mm) packed with this phase showed good separation efficiency (N~10,000-16,000) comparable to that of a commercial column packed with 5 ${\mu}m$ C18 silica particles.

• Mycobiology
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• v.36 no.4
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• pp.260-265
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• 2008

Cyclic voltammetric measurements were performed for Co(II), Ni(II), Cu(II) and Zn(II) complexes of 1 : 1 alternating copolymer, poly(3-nitrobenzylidene-1-naphthylamine-co-succinic anhydride) (L) and Ni(II) and Cu(II) complexes of 1 : 1 alternating copolymer, poly(3-nitrobenzylidene-1-naphthylamine-co-methacrylic acid) ($L^1$). The in vitro biological screening effects of the investigated compounds were tested against the fungal species including Aspergillus niger, Rhizopus stolonifer, Aspergillus flavus, Rhizoctonia bataicola and Candida albicans and bacterial species including Staphylococcus aureus, Escherichia coli, Klebsiella pneumaniae, Proteus vulgaris and Pseudomonas aeruginosa by well diffusion method. A comparative study of inhibition values of the copolymers and their complexes indicates that the complexes exhibit higher antimicrobial activity. Copper ions are proven to be essential for the growth-inhibitor effect. The extent of inhibition appeared to be strongly dependent on the initial cell density and on the growth medium. The nuclease activity of the above metal complexes were assessed by gel electrophoresis assay and the results show that the copper complexes can cleave pUC18 DNA effectively in presence of hydrogen peroxide compared to other metal complexes. The degradation experiments using Rhodamine B dye indicate that the hydroxyl radical species are involved in the DNA cleavage reactions.

• Journal of the Korean Society of Clothing and Textiles
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• v.12 no.2 s.27
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• pp.217-223
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• 1988

This study is to examine the cleaningproof by dry cleaning runs and parts(shoulder, belly, butt) of garment leathers tanned chrome. This study is composed of three methods of test; color difference test, surface view by scanning electron micrographs, mechanical properties measurement by KES-FB system. The results obtained were as follows: 1. In stiffening of parts of sample, the belly is the best degree in smoothness, fullness, softness. But that of the butt have been found to be the worst degree and to be thick. 2. In fading of parts, the shoulder is an extreme case, but the belly is the best among three parts. 3. In dry cleaning runs, the view after 3 runs has been found to be the best result. 4. The stiffening after dry cleaning 1 run have been low grade, for the sample absorb much solvent of dry cleaning. And, the fading and the decoloration are to be worse after 5 runs. Because the leather surface is affected by dry cleaning runs.

• Journal of Sensor Science and Technology
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• v.21 no.5
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• pp.345-351
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• 2012

Biomimetic terpene sensors which have high sensitivity and stability have been fabricated using moleculary imprinted polymer (MIP) technology. Since it is impossible to make a resistive type sensor due to the high resistance of MIP, we improved the sensor by adding conductive polymers. We investigated the sensitivity of resistive type sensors with nano particles depending on the amount of conductive polymers. The MIP membrane contained the methacrylic acid as functional monomer and ethylene glycol dimethacrylate as cross linker, which formed specific cavities originated by the target terpene molecules. The mixture of MIP and the conductive polymer was coated on the patterns of interdigit electrodes on the alumina substrate. The fabricated sensors showed their highest specific sensitivities exposed to 500 ppm target gases : limonene 0.055 at 40% of amount of conductive polymers and geraniol $5.84{\times}10^{-4}$ at 20% of amount of conductive polymers. In conclusion, we found that the terpene sensors are affected by the target molecules, functional monomers and the conductive polymers.