• Proceedings of the Korean Fiber Society Conference
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• 1998.04a
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• pp.58-62
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• 1998

고분자 블렌드의 열역학적 상용성은 고분자 혼합물의 혼합 엔트로피가 무시할 수 있을 정도로 작기 때문에 성분 고분자 사이의 강한 분자간 인력에 의한 음의 값의 혼합 엔탈피에 의해서 유도되어진다. 상용성 고분자 블렌드를 얻기 위하여 도입되어질 수 있는 분자간 상호인력으로는 수소결합$^1$, 쌍극자-쌍극자 상호작용$^2$, 이온-쌍극자 상호작용$^3$, 산-염기 상호작용$^4$, 전이금속 복합체 형성$^{5}$ , 전하이동 복합체 형성$^{6}$ 등이다.(중략)

• Proceedings of the Korean Society of Applied Pharmacology
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• 1992.05a
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• pp.65-65
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• 1992

소프트하이드로겔은 소재의 친수-소수성, 조성, 가교도, 약물의 물성에 의해 약물방출을 조절할 수 있었으며 또한 특이적인 전연성, 탄성에 의해 약물의 0차방출이 가능하였다. 메타크릴산-IPN-소프트하이드로겔은 현저하게 높은 PH의존성 팽윤도와 이에 따른 약물조절방출능을 보였으며 아크릴산-IPN-소프트하이드로겔은 우수한 점착성을 나타내었다. 이상 연구된 소프트하이드로겔들은 새로운 소재로서 개발대상으로 설정된 조절방출성 제제로의 활용성을 기대되었다.

• Korean Journal of Environmental Agriculture
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• v.18 no.4
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• pp.316-320
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• 1999

The purpose of this research was to estimate dewatering characteristics of generating water treatment plant by dewatering velocity, suitable polymer and mixing condition. Zeta potential of sludge in storage tank was negative and in case of adding cation, anion and nonion polymer for sludge conditioning, specific resistance coefficients of conditioned sludge were similar at zeta potential -5㎷. But above zeta potential -15㎷, canon polymer was more effective than others for reduction of specific resistance coefficients. Using of cation acrylate polymer showed better dewatering coefficients than cation methacrylate polymer.

• Applied Chemistry for Engineering
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• v.7 no.5
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• pp.946-953
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• 1996

The effect of absorbed dose, dose rate, cationic salts and solvent on the grafting yield was evaluated when acrylic acid was grafted onto polypropylene fabric by simultaneous irradiation process. Low dose rate when irradiated with the same absorbed dose led to a high grafting yield. On the other hand, the grafting yield increased with dose rate in case the total irradiation times is equal, and the initial rate of grafting was found to be proportional to be 0.74 power of dose rate. $FeSO_4{\cdot}7H_2O$ was found to be the most effective additive for high grafting yield, while inhibiting homopolymer formation. It was impossible to induce radiation grafting without the addition of the certain amount of salt, but the grafting yield decreased with increasing metallic salt.

• Membrane Journal
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• v.12 no.4
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• pp.255-261
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• 2002

Poly(vinyl alcohol) (PVA) membranes crosslinked with poly(acrylic acid-co-maleic anhydride) (PAM) as a polymeric crosslinking agent were prepared to investigate the pervaporation performance for the dehydration separation of aqueous ethanol solution. The characteristics of the resulting membranes crosslinked(x) were analysed by FT-IR and water swelling test. The water swelling decreased with increasing crosslinking agent content. The crosslinked PVA membranes with PAM showed lower water swelling than those of PVA membrane crosslinked with glutaraldehyde and modified PVA membrane. The swelling of water molecules in the crosslinked PVA membranes is more restricted by both chemical crosslinking between PVA and polymeric crosslinking agent chains and physical crosslinking by the entanglement between the PVA and polymeric crosslinking agent chains. For the pervaporation of aqueous ethanol solution through the crosslinked membrane, as the contents of crosslinking agent increased, the separation factor increased while the permeation flux decreased. The separation factor slightly decreased and permeation flux increased with increasing feed water content. As a result it could be considered that PVA-PAM membranes suppressed the plasticization effect even in the range of high water concentration in fled.

• Applied Chemistry for Engineering
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• v.4 no.2
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• pp.308-317
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• 1993

The study is related to the synthesis of acrylic acid by selective oxidation of acrolein on Mo-V-W multicomponent mixed oxide catalysts. Mo-V-W-O(WVM), Mo-V-O/Mo-W-O(VM/WM), Mo-W-O/Mo-V-O(WM/VM) and mechanical mixtures of Mo-V-O and Mo-W-O(M-VM+WM) were prepared and characterized by BET, XRD, SEM and EPMA. Catalytic activity of these catalysts was tested in a continuous fixed bed reactor. In WVM catalysts small amount of tungsten added to VM increased surface area and selectivity of acrylic acid, but excess amount of tungsten decreased reaction rate of acrolein and selectivity. VM/WM catalysts, VM supported on WM, showed higher activity and selectivity than WM/VM catalysts where WM is supported on VM. Phase cooperation between WM and VM was observed in mechanical mixture of WM and VM and they showed higher yield than WM or VM.

• Applied Chemistry for Engineering
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• v.8 no.6
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• pp.934-938
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• 1997

Acrylic acid was grafted onto the peroxidized cellulose which was stored at room temperature for 20 days after ${\gamma}$-ray irradiation in air. The effect of acids and metallic salts on the grafting yields was determined. The addition of both the acid and metallic salt was found to accelerate the grafting yield much more than the only metallic salt, and the addition of $FeSO_4{\cdot}7H_2O$ led to much higher grafting yield than that of $CuSO_4{\cdot}5H_2O$. The effect of acid on the grafting yield increased by the order $H_2>SO_4>HCl>HNO_3>CH_3COOH$. With the addition of $H_2SO_4$, the grafting yield rapidly increased up to $7{\times}10^{-2}$M, and then levelled off.

• Clean Technology
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• v.17 no.4
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• pp.325-328
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• 2011

Atom-efficient preparation of 9, 9'-bis[4-(2'-hydroxy-3'-acryloyloxypropoxy) phenyl]fluorene (3), the extensively used building block for fluorene-containing acrylic epoxy polymers has been described. The epoxide ring opening esterification of 9, 9-bis[4-(glycidyloxy)phenyl]fluorene (1) with acrylic acid was catalyzed by some onium salts such as quaternary ammonium and phosphonium salts. While the coupling reactions depend greatly on the kind of the onium salts, the reaction of 9, 9-bis[4-(glycidyloxy)phenyl]fluorene (1) with acrylic acid proceed most efficiently in the presence of a catalytic amount of tetrabutylphosphonium bromide at $110^{\circ}C$ with 90% yield. This reaction is a cleaner reaction that minimizes the use of reactants and the production of chemical wastes.

• Polymer(Korea)
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• v.30 no.6
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• pp.550-555
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• 2006

The coating material for the ink-jet printing paper tends to be waterbase as the waterbase ink-jet ink is used more widely. Waterbase coating material consists of alumina sol as a pigment, poly(vinyl alcohol) as a main binder and polymeric additive for improving properties. In this study, polymeric auditive was synthesized by combining one or toto monomers among methacrylic acid, acrylic acid and acrylamide to the basic monomers, styrene and n-butylacrylate. The properties of printability such as ink absorption, ink spreading, and optical density, glossiness and water resistance were investigated by changing the kinds of surfactants, the composition of monomers and the structure of polymer particles. Results showed that materials containing anionic surfactant and/or acrylic acid had problems in com-patibility with alumina sol. Also, coating materials containing acrylamide had good printability and lout glossiness while those containing methacrylic acid did not have good printability and high glossiness.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.5
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• pp.3653-3659
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• 2015

This paper describes the reactive compatibilization of blends of a wholly aromatic thermotropic copolyester liquid crystalline polymer (TLCP) with random copolymers of ethylene and acrylic acid (EAA) and their salts. Blends were prepared by melt mixing in an intensive batch mixer, and the formation of a graft copolymer due to acidolysis between the TLCP and the acrylic acid group of the ionomer was evaluated. Chemical reaction was assessed by torque measurement during melt mixing and by thermal analysis and morphological observation. The Na-salt of the EAA ionomers was especially effective at promoting a grafting reaction. The extent of reaction depended not only on the cation, but also composition of the ionomer and reaction time. The product of the grafting reaction between the TLCP and a sodium-neutralized ionomer proved to be an effective compatibilizer for TLCP and EAA ionomers.