• Elastomers and Composites
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• v.36 no.1
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• pp.22-29
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• 2001

For a purpose of recycling of waste tires, composites of 10-60wt% recycled tire crumb blended with high density polyethylene(HDPE) were prepared, and their mechanical properties such as tensile strength, elongation at break, tensile modulus and impact strength were investigated as a function of tire crumb content. Ethylene-acrylic acid(EAA) copolymer was introduced by 10phr as a compatibilizer and the mechanical properties of the composites were measured. For the blend composition of 40wt% tire crumb content showing improved impact strength, the mechanical properties were measured by varying the EAA content of 5-15phr. All blends, whether modified or unmodified, showed a gradual improvement in impact strength as the tire crumb content increased, but the other properties decreased compared with the pure HDPE. In particular, the addition of EAA copolymer to the tire crumb content over 30wt% showed substantial improvement in impact strength. There was no significant effect of tire crumb size on impact strength of the composites.

• Membrane Journal
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• v.31 no.4
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• pp.268-274
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• 2021

One of the chronic problems in the issue of global warming is the emission of greenhouse gases. Carbon dioxide (CO₂), which accounts for the highest proportion of various greenhouse gases, has been continuously researched by humans to separate it. From this point of view, a poly(vinyl alcohol) (PVA)-based copolymer with acrylic acid monomer was utilized in a gas separation membrane in this study. We employed a free radical polymerization to fabricate PVA-g-PAA (VAA) graft copolymer. It was utilized in the form of a composite membrane on a polysulfone substrate. The proper amount of acrylic acid reduced the crystallinity of PVA and increased CO₂ solubility in separation membranes. In this perspective, we suggest the novel approach in CO₂ separation membrane area by grafting and solution-diffusion.

• Proceedings of the Membrane Society of Korea Conference
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• 1998.10a
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• pp.73-74
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• 1998

1. Introduction : We have researched to separate water effectively from aqueous pyridine solution. In our previous papers, we have proposed new separation mechanism, in-situ complex, which is different from solution-diffusion and accelerated transport by hydrogen bonding. We have adopted in-situ complex mechanism to membranes containing phosphoric acids as well as acrylic acid and sulfonic acid in copolymer for dehydration of pyridine.

• Polymer(Korea)
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• v.29 no.2
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• pp.127-134
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• 2005

The relationships among mechanical properties, rheological properties, and morphology by reactive extrusion based on commingled pckaging film wastes contains polypropylene (PP) pckaging film system [PP/polyethylene (PE)/aluminum (Al)/poly(ethylene terephthalate) (PET)] and Nylon packaging film system[Nylon/PE/linear-low density polyethylene (LLDPE)] were investigated to improve the compatibility and toughness of these wastes using various compatibilizers such as ethylene vinylacetate (EVA), styrene-ethylene/butylene-styrene triblock copolymer (SEBS), styrene-ethylene/butylene-styrene-graft-maleic anhydride copolymer (SEBS-g-MA), polyethylene-graft-maleic anhydride (PE-g-MA), polypropylene-graft-maleic anhydride (PP-g-MA) , polyethylene-graft-acrylic acid (PE-g-AA) and polypropylene-graft-acrylic acid (PP-g-AA). Compared with simple melt blend system, the blends showed improvement of about $50\%$ increase in physical properties when SEBS and EVA were added. However, SEBS-g-MA thermoplastic elastomer which is highly reactive with amine terminal group of nylon, resulted in about $200\%$ increase in impact strength. This compatibilization effect resulted from the increase of interfacial adhesion and the reduction of domain size of dispersed phase in PP/Nylon blend system.

• Polymer(Korea)
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• v.31 no.5
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• pp.369-373
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• 2007

In this study, solvent-free pressure sensitive adhesives (PSA) using acrylic copolymer was prepared by UV radiation to investigate the effect of comonomer on the adhesion properties. Adhesive force value of PSA was increased with the amount of comonomer having shorter side chain due to the enhanced intrinsic surface energy. Peel and shear strength were also influenced by chemical properties of comonomer. The addition of comonomer, ethyl and n-butyl acrylate allows PSA sample with high peel and shear strength. This nay be explained in terms of correlation between loss modulus and glass transition temperature of PSA. As the addition of acrylic comonomers with long side chain length decreases the loss modulus of PSA, the deformation of PSA can not be inhibited.

• Polymer(Korea)
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• v.29 no.4
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• pp.380-384
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• 2005

Fluoroalkyl methacrylate and acrylic acid were bulk radical copolymerized in the presence of pure sodium montmorillonite or macromer intercalated sodium montmorilonite to get a fluorinated acrylic ionomer/sodium montmorillonite composite, and their physical properties, such as X-ray diffraction pattern, tensile properties, and water uptake, were examined. These composites were used to preparean ionic acrylic polymer-platinum composite (IPMC). The current and deformation responses of these IPMCs by external voltage applied across the platinum electrodes deposited on both sides of IPMC showed that the cation migration from anode to cathode was suppressed in the presence of sodium montmorillonite, causing reduced current and deformation.

• Polymer(Korea)
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• v.27 no.1
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• pp.17-25
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• 2003

Using atom transfer radical polymerization (ATRP), polystyrene macroinitiators and polystyrene-b-poly(t-butyl acrylate) (PS-b-P(tBA) block copolymers were synthesized by CuBr/PMDETA catalyst system in solution. After hydrolysis, polystyrene-b-poly(acrylic acid), amphiphilic block copolymers, were formed. Subsequent neutralization of polyacid block led to the block ionomers. The molecular weight of the synthesized PS-b-P(tBA) block copolymers was easily-controlled to 5000-10000 and their distributions were less than 1.2. The chemical structures of the synthesized block copolymers were characterized by $^1$H-NMR and FT-IR. In the DSC thermograms, $T_g$ appeared in the vicinity of 100 $^{\circ}C$ because of higher styrene content. In addition, the phase separation of the block ionomers was observed by TEM.

• The International Journal of Costume Culture
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• v.6 no.2
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• pp.134-146
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• 2003

Polyester of linear homopolymer poly(ethylene terephthalate)(PET) was chemically modified through the formation of branched copolymer to improve the undesirable properties of fiber. Photo-induced graft copolymerization of the acrylic monomers acrylic acid (AA) and methyl acrylate (MA) in the liquid and vapor phase, respectively, onto N,N-dimetylformamide (DMF)-pretreated PET fibers was carried out. The effect of various synthesis conditions and DMF pretreatment of the PET on the graft yield was investigated. Grafting mechanism was analysed. The grafting was promoted by increasing DMF pretreatment temperature and amount of DMF retention in the fiber. The increasing biacetyl and monomer flow time, and irradiation time enhanced the grafting up to a certain amount and thereafter it decreased.

• Elastomers and Composites
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• v.49 no.1
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• pp.37-42
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• 2014

Terpolymer polymerized carbon monoxide, ethylene and propylene as monomer, Polyketone is low-cost material compared with general engineering plastics such as polyamide, polyester, polycarbonate. Moreover, it is excellent in mechanical properties, chemical resistance, fuel permeability and abrasion resistance. So, it is attracted attention as the environmental friendly material to replace conventional engineering plastics. In this study, has been prepared Polyketone/Rubber (Ethylene propylene copolymer, Acrylonitrile butadiene rubber, Ethylene acrylic rubber) blends to improve heat resistance and investigated characteristic behavior after heat/oil aging.

• Fashion & Textile Research Journal
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• v.14 no.3
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• pp.472-477
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• 2012

The conditions of wet spinning were considered in order to prepare the fine denier of acrylic fiber. Polyacrylonitrile copolymer was synthesized by the copolymerization of acrylonitrile (AN) and methyl acrylate (MA) initiated by an aqueous sulfite-chlorate redox system. Acrylic fiber was manufactured through wet-spinning in a dimethyl formamide (DMF) system. The conditions of wet-spinning were investigated by i-value, spinning speed, diameter of spinneret, draw ratio, water content of spinning dope and morphology of protofiber. The physical properties of fibers were investigated by Instron. In this experiment, the minimum i-value decreased with the decreasing spinneret diameter, an increased spinning speed, and an increased coagulation bath (CBC) concentration. The maximum draw ratio increased with an increased CBC. The optimum CBC and water content of the spinning dope were 60%-65% and 3.5%, respectively. The tenacity at the breaking point increased with a decreased fineness of fiber. The elongation at breaking point was almost the same value as a function of the fineness of fiber.