• 한국막학회:학술대회논문집
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• 한국막학회 1996년도 추계 총회 및 학술발표회
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• pp.86-87
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• 1996

IPN (Interpenetrating Polymer Network) is a mixture of two or more crosslinked polymers with physically interlocked network structures between the component polymers. IPN can be classified as an alloy of thermosets and has the characteristics of thermosets such as the thermal resistance and chemical resistance and also has the characteristics of polymer alloys with enhanced impact resistance and amphoteric properties. The physical interlocking during the synthesis restricts the phase separation of the component polymer with chemical pinning process, thus the control of morphology is possible through variations of the reaction temperature and pressure, catalyst concentration and crosslinking agent concentration. Finely dispersed domain structure can be obtained through IPN synthesis of polymer components with gross immiscibility. In membrane applications, particularly for the separation of liquid mixtures, crosslinked polymer component with specific affinity to the permeate is needed. With the presence of the permeant-inert polymer component, the mechanical strength and the selectivity of the membranes are enhanced by restricting the swelling of the transporting polymer component networks.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 C
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• pp.944-946
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• 1999

The thermal stability of the post cured epoxy-polysiloxane IPN structure was observed by using DSC and TGA. As the post curing time increased the glass transition temperature increased and the secondary exothermic peak disappeared. The thermally decomposing activation energy calculated by using Kissinger expression was 225.6 kJ/mol. The thermal stability of the grafted IPN of epoxy and silicon compound depends on the composing ratio and post curing conditions of time and temperature.

• 폴리머
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• 제38권5호
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• pp.588-595
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• 2014

A semi-interpenetrating polymer network (semi-IPN) hydrogel composed of crosslinked chitosan and poly (acrylic acid-co-crotonic acid) was prepared in the presence of glutaraldehyde (GA) as a crosslinker. Fourier-transform infrared, thermogravimetric analysis and scanning electron microscopy were employed to confirm the structure of the semi-IPN hydrogel. The swelling capacity of hydrogel was shown to be affected by the monomers weight ratio, chitosan content, initiator and GA concentrations. The results also indicated that the semi-IPN hydrogel had different swelling capacity at various pHs. Additionally, the swelling behavior of the hydrogel was investigated in aqueous solutions of NaCl, $CaCl_2$, and $AlCl_3$.

• 대한의용생체공학회:의공학회지
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• 제17권3호
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• pp.291-296
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• 1996

Poly(ethylene glycol)(PEG) macromers terminated with diacrylate Iyoups and interpenetrating poly- mer networks(IPN) composed of poly(hydroxyethyl methacrylate)(PHEMA) or poly(hydroxyethyl methacrylate-co-hydronypropyl methacrylate-co- N-vinyl pyrrolidone ) [ P( HEM A-co- HPM A-co- NVP) ] and PEG macromer were synthesized with the aim of obtaining protein adsorption resistant soft contact lens. Polymerization of PEC macromer resulted in the formation of cross-linked gels due to the multifunctionality of macromer. Crosslinked P(HEMA) or P(HEMA-co-HPMA-co-WVP) chains were interpenetrated into the cross-linked three-dimensional networks of PEG. It was found that albumin adsorption onto the contact lens prepared by P(HEMA-co-HPMA-co-NVP) /PEG IPW decreases with an increase of molecular weight of PEG. Also, it was found that albumin adsorption onto the both contact lens decreases with an increase of concentration of PEC macromer in the IPN preparation. There are also more adequate in the bioinertnen for the contact lens by P(HEMA)/PEG IPN or P (HEMA-co-HPMA-co-NVP)/PEG IPN than that by P(HEMA) or P(HEMA-co-HPMA-co-NVP)

• E2M - 전기 전자와 첨단 소재
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• 제10권7호
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• pp.651-658
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• 1997

In this paper, effect of interpenetrating polymer network(IPN) introduction on the dielectric properties, heat proof properties, internal structure and defects of the Epoxy/SiO$_2$composite materials, were investigated. we reported a relation between network structures and electrical properties, especially dielectric characteristics with variation of network structures for epoxy composite materials. According to experimental results, the specimens which have single network structures have lower dielectric constant than interpenetrating polymer network(IPN) specimens, but have relatively larger dependency to variation of temperature and frequency. It was confirmed that change of structures is attained by introducing of IPN to insulating materials. Therefore it is counted that introduction of multiple structure including IPN is necessary to improve heat proof and electrical properties.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.156-159
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• 2000

In this paper, the physical and electrical properties of epoxy composites are investigated at boiling absorption condition to observe the influences of moisture. Also, in order to improve water resistance of matrix resin, IPN method was introduced and the influence was investigated. In order to analyze the basic physical properties of samples, scanning electron microscopy method was utilized, and impulse voltage dielectric strength was measured. As a result, it was verified that, in case of IPN samples, the ratio of moisture absorption was decreased due to the improvement of adhesion strength, and impulse voltage dielectric strength of SN sample was degraded abruptly as boiling time and filler content were increasing, while IPN samples were slowly degraded due to the improvement of adhesion strength.

• 유변학
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• 제2권1호
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• pp.79-86
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• 1990

상업적으로 많이 이용되는 불포화 폴리에스터

• 한국막학회:학술대회논문집
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• 한국막학회 1999년도 춘계 총회 및 학술발표회
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• pp.56-60
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• 1999

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.870-870
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• 2006

• Biotechnology and Bioprocess Engineering:BBE
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• 제6권5호
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• pp.326-331
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• 2001

With the aim of developing of pH-sensitive controlled drug release system, a poly(Llysine) (PLL) based cationic semi-interpenetrating polymer network (semi-IPN) has been synthesized. This cationic hydrogel was designed to swell at lower pH and de-swell at higher pH and therefore be applicable for achieving regulated drug release at a specific pH range. In addition to the pH sensitivity, this hydrogel was anticipated to interact with an ionic drug, providing another means to regulate the release rate of ionic drugs. This semi-IPN hydrogel was prepared using a free-radical polymerization method and by crosslinking of the polyethylene glycol (PEG)-methacrylate polymer through the PLL network. The two polymers were penetrated with each other via interpolymer complexation to yield the semi-IPN structures. The PLL hydrogel thus prepared showed dynamic swelling/de-swelling behavior in response to pH change, and such a behavior was influenced by both the concentrations of PLL and PEG-methacrylate. Drug release from this semi-IPN hydrogel was also investigated using a model protein drug, streptokinase. Streptokinase release was found to be dependent on its ionic interaction with the PLL backbones as well as on the swelling of the semi-IPN hydrogel. These results suggest that a PLL semi-IPN hydrogel could potentially be used as a drug delivery platform to modulate drug release by pH-sensitivity and ionic interaction.