• Polymer(Korea)
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• v.27 no.4
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• pp.313-322
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• 2003

The morphology of poly(ethylene terephthalate) (PET)/poly(m-xylene adipamide) (MXD-6) blends, which was prepared by adding compatibilizer and interchange reaction agent, was investigated. The morphological change in the stretched blend films was also studied. The stretched film showed a dispersed MXD-6 fibril. This fibril became finer with increasing draw ratio (DR). The addition of compatibilizer and interchange reaction agent had no effect on the improvement of interfacial adhesion but caused a defect between the continuous phase and the dispersed phase, leading to the formation of irregular fibril. The change in the superstructure of blends with composition and draw ratio was examined with light scattering (LS). The H$\sub$v/ LS patterns showed a double-cross type pattern consisting of a broad rod-like pattern and a sharp cross streak. On the basis of the model calculation of the H$\sub$v/ pattern, it was found that the appearance of the double-cross type pattern was attributed to the stacking of crystals oriented along the draw direction. The crystals were gradually oriented to the stretching direction with draw ratio. As a result, the high level of orientation was obtained fur the sample of draw ratio is 6.0.

• Polymer(Korea)
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• v.36 no.6
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• pp.727-732
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• 2012

Baroplastic poly(butyl acrylate) (PBA)/polystyrene (PS) blends were prepared by mixing PBA and PS emulsions synthesized by cationic and anionic surfactant, respectively. Interestingly, the heterocoagulation of nanoparticles have found to be affected strongly by emulsion concentration but the blends have been prepared with almost same compositions regardless of the amount of reactants. Utilizing this method, PBA/PS/Si hybrid nano-blends were prepared successfully via electrostatic attraction forces between PBA, PS and silica nanoparticles. The hybrid nano-blend having 2 or 5 wt% of silica was then processed to a semi-transparent film at $25^{\circ}C$ under 13.8 MPa for 10 min, which showed 3.0 MPa of tensile strength and 25 MPa of elastic modulus. Therefore, the heterocoagulation technique can be used for preparing baroplastics with uniform compositions of polymer and silica nanoparticles.

• Polymer(Korea)
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• v.35 no.6
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• pp.543-547
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• 2011

A study has been done to enhance the mechanical properties and processability of electrically conductive polyaniline(PANI) without the polymer's structural alternation. Functionalized acid doped PANI (PANI-DBSA) was prepared by an emulsion polymerization, and dodecylbenzenesulfonic acid (DBSA) played both roles of surfactant and dopant. Also, PANI-DBSA was solution cast blended with high impact polystyrene (HIPS) to produce PANI-DBSA/HIPS blend film. The structure and electrical properties of the conducting polymer blends were observed through UV-vis and FTIR/ATR spectroscopy. A study of the blend was carried by focusing on observation of mechanical and electrical properties based on dispersibility and changes in polymer morphology. The conductivity of the blends was increased by increasing the content of PANI-DBSA, and the sudden increase of conductivity to $3.5{\times}10^{-4}$ S/cm was observed even under a low content of 9 wt%. There was a strong association of continuous network formation with percolation and conductivity in the conducting polymer blends.

• Textile Coloration and Finishing
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• v.20 no.6
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• pp.1-7
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• 2008

The effects of $TiO_2$ contents and UV irradiation treatment on the surface properties of PLA films embedded with $TiO_2$ nanoparticle were investigated. Whereas UV irradiation decreased reflectance of the treated PLA films proportionally with increasing UV energy, the reflectance of PLA/$TiO_2$ films increased with increasing UV energy. The UV irradiation treatment caused PLA/$TiO_2$ blend films more polar as indicated in the generation of new carbonyl group and decrease in zeta potentials, which was more pronounced with the introduction of $TiO_2$. Upon UV irradiation, $TiO_2$ particles appeared on the film surface as observed in SEM images. The PLA/$TiO_2$ blend films showed photocatalytic properties such as photobleaching of methylene blue, deodorization of ammonia and antimicrobial activity in comparison with pure PLA films.

• Proceedings of the KIEE Conference
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• 1998.11c
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• pp.875-877
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• 1998

In this paper, the physical and electrical properties of electrical insulating materials due to linear low density polyethylene (LLDPE)/ethylene vinyl acetate(EVA) blends are studied. The peak of LLDPE/EVA made by blend ratio of 70:30 at $2{\theta}=21.4^{\circ}$ in the results of XRD is higher than the others. In the experiment for electrical conduction properties in order to investigate the electrical properties of specimen, it is confirmed that electrical conduction is increased with the increase of molecular motions with the increase of temperature.

• Journal of the Korean Society of Safety
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• v.19 no.3 s.67
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• pp.51-56
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• 2004

Conductive polymer blends and composites are widely used for different safety application such as electrostatic charge dissipation(ESD), electromagnetic interference(EMI) shielding, electrostatic prevention and safety chemical sensor. In order to prepare a impedance-type humidity sensor that is durable at high humidities and high temperature, electically conductive polymer blends based on diallyldimethylammonium chloride(DADMAC) and epoxy were prepared in this study. The polymer blends type conductive ionomer exhibits reaction each other DADMAC and epoxy in FT-IR and DSC analysis. The blends material was traced by new peak at 1600cm-1 and appeard improvement of thermal resistance by melting point shift. Alumina substrate was deposited a pair of gold electrodes by screen printing. The blend material were spin-coated with a thin film type on the surface of alumina substrate. The polymer bleld type sensor exhibits a linear impedance increasing better than DADMAC coated humidity sensor. Also it shows good sensitivity, low hysteresis and durability against high humidity.

• Elastomers and Composites
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• v.41 no.1
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• pp.3-9
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• 2006

Optimal conditions for preparation of starch/PVA blends were investigated with the consideration of factors that may influence mechanical properties of the blends. Multiplex mixture optimal method as a statistical method were performed and then tensile strength, strain at break, Young's modulus and tear strength of films of the blends were measured to determine the optimal conditions for preparation. The mechanical properties needed for the degradable agricultural mulch were the target of this experiment. Results showed that although the strain at break was a little insufficient, the other properties were very close to the target. This means that the mechanical properties of the film from this blend as a whole are very compatible with those of the reference mulch.

• Korean Chemical Engineering Research
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• v.45 no.4
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• pp.384-390
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• 2007

In this study, electroless plating of copper was performed on PET film by using the blend of supercritical $CO_2$ and plating solution. The optimum volumetric ratio of supercritical fluid and plating solution was found to be 1:9 and dispersion property was poor at $CO_2$ vol% langer than 10%. Electroless plating of copper was best at $25^{\circ}C$ and 15 MPa. Role of added supercritical $CO_2$ is not to increase solubility but to disperse and maintain Cu-particles as the 1st particles.

• 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.

• Journal of the Korean Wood Science and Technology
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• v.48 no.1
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• pp.95-106
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• 2020

The purpose of this study was to determine the effects of coniferous essential oils (EOs) blended films on insect repellence and crop productivity. Low-density polyethylene (LDPE) film is widely used, especially in agriculture and for food packaging. Ethylene vinyl acetate was blended with LDPE to reduce volatilization of EOs. An EO from Japanese cypress (Chamaecyparis obtusa) was incorporated into the blend film to conduct field research on antimicrobial and insect repellent properties. Among the various concentrations of EO, the highest concentration (2.5%) showed the highest efficiency in terms of pesticidal activity. The ability to inhibit microbial growth can be explained by the lipophilic properties of the EO component, and many studies have already demonstrated this. Agricultural films containing all types of EO have been tested on various crops such as chili, cucumber, Korean melon and have been able to verify their effectiveness in avoiding pests and increasing yields. From these results, it was found that it is reasonable to use a modified film such as a composite film containing an EO for agriculture. Thus, the modified film containing EO has undoubtedly shown impressive potential for reducing the use of pesticides in a variety of ways, not only for agricultural mulching film but also for food and agricultural product packaging. This product is an environmentally friendly chemical and is safe for agricultural and industrial and food packaging applications, among others. In particular, the use of agricultural films significantly reduces the use of pesticides, suggesting that farmers can increase their incomes by reducing working hours and costs, and increasing production.