• 제목/요약/키워드: Methacrylic acid

검색결과 144건 처리시간 0.027초

pH 의존성 Methacrylic acid 공중합체의 팽윤특성 (pH-dependent Swelling Properties of Methacrylic Acid Copolymer Hydrogels)

  • 김경충;이승진
    • 약학회지
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    • 제33권6호
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    • pp.372-376
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    • 1989
  • Equilibrium swelling and pH-sensitivity of a polyelectrolyte copolymer hydrogel were controlled by employing copolymers with different hydrophilic-hydrophobic balances. Model pH-sensitive hydrogels, e.g., poly(methacrylic acid), poly(methacrylic acid-co-acrylamide), poly(methacrylic acid-co-2-hydroxyethylmethacrylate), poly(methacrylic acid-co-styrene) were synthesized at various monomer compositions. As hydrophobicity of the copolymer hydrogels increased, the equilibrium swelling decreased while the pH-sensitivity increased. In the case of poly(methacrylic acid-co-acrylamide), polymer-polymer interaction significantly affected the equilibrium swelling and provided a wide range control of pH-sensitivity.

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Anti-gelling Effect of Poly(methacrylic acid, methyl methacrylate) on Cefuroxime Axetil Composition

  • Shim, Ji-Yeon;Wang, Hun-Sik;Kwon, Min-Chang;Park, Jun-Sang
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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    • pp.237.1-237.1
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    • 2003
  • Cefuroxime axetil, a broad spectrum antibiotic, has been known to form a gelatinous mass in contact with aqueous media, which could lead to poor dissolution. Therefore, this study was conducted for removing the gelling phenomenon and thereby obtaining a favorable dissolution profile. We have found that the addition of poly (methacrylic acid, methyl methacrylate) could not only inhibit the tendency of cefuroxime axetil to form a gel but also showed the good dissolution profile compared to the formula without poly (methacrylic acid, methyl methacrylate). (omitted)

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ZSM-5 위에 지지된 Heteropolyacid 하에서 Methacrylic acid와 Ethylene glycol의 에스테르화 반응 (Esterification of Methacrylic acid with Ethylene glycol over Heteropolyacid supported on ZSM-5)

  • Prabhakarn, A.;Fereiro, J.A.;Subrahmanyam, Ch.
    • 대한화학회지
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    • 제55권1호
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    • pp.14-18
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    • 2011
  • methacrylic acid과 ethylene glycol과의 에스테르화 반응을 ZSM-5에 지지된 heteropolyacids [HPA: $H_4SiW_{12}O_{40}$(STA)와 $H_3PW_{12}O_{40}$(PTA)] 하에서 수행하였다. 비교를 위하여, 지지하지 않은HPA, $H_2SO_4$, $BF_3$와 PTSA 하에서 같은 반응을 수행하였다. 연구한 촉매 중에서, HPA는 $H_2SO_4$, $BF_3$와 PTSA와 비교하여 더 좋은 활성을 보여주었다. 촉매 활성을 HPA지지 ZSM-5 촉매와 비교하였는데, 그 결과 ZSM-5위에 지지된 30 wt% PTA는 bulk PTA와 거의 같은 활성을 나타내었다. 이 반응은 methacrylic acid에 관하여 1차 속도 법칙을 따랐으며, 반응 생성물은 $^1H$-NMR과 FT-IR을 이용하여 확인하였다.

아크릴산과 메타크릴산의 효소적 배당화 (Enzymatic Glycosylation of Acrylic Acid and Methacrylic Acid)

  • 박돈희;김해성
    • KSBB Journal
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    • 제16권1호
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    • pp.82-86
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    • 2001
  • Glyco-acrylate and methacrylate were synthesized by lipase-catalyzed glycosylation of acrylic acid, methacrylic acid and their vinyl esters with $\beta$-methyl fructoside and glycerol in t-butanol as a reaction medium. At the optimum conditions for enzymatic glycosylation of acrylic acid and vinyl methacrylate, we attained up to 80% conversion for glyco-acrylate from acrylic acid and 90% conversion for glyco-methacrylate from vinyl methacrylate. The polymerizable glyco-acrylates and methacrylate have biomedical application as hydrophilic monomers and hydration modifiers to be use for hydrogel contact lens formulation.

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포스핀류가 배위된 팔라듐 착물에 의한 불포화카르복실산의 카르보닐화 고리반응 (제 3 보). 팔라듐 (0, II)-포스핀계 착물에 의한 불포화카르복실산의 카르보닐화 반응 및 그의 이론적 연구 (Carbonylative Cyclization of Unsaturated Carboxylic Acids by Palladium Complexes with Phosphines [III] Palladium (0, II)-Phosphine Complexes Catalyzed Cabonylation of Unsaturated Carboxylic Acids and It's Theoretical Studies)

  • 도명기;김봉곤;정맹준;송영대;박병각
    • 대한화학회지
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    • 제37권10호
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    • pp.903-909
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    • 1993
  • 팔라듐(0, II)-포스핀계 착물을 촉매로 하여 crotonic acid, methacrylic acid 및 3-butenoic acid 같은 불포화가크복실산의 카르보닐화 고리반응에서 생성가능한 물질의 구조를 확인하고, 그 반응메카니즘을 MM2 와 EHMO 계산에 의해서 추정하였다. 이 반응은 ${\pi}$ -착물을 거쳐 금속 함유 고리화합물을 만든 다음 산화성 첨가반응과 환원성 제거반응이 일어나 진행된다. ${\pi}$ -착물을 안정화시키는 crotonic acid, methacrylic acid 등은 카르보닐화 고리반응이 진행되지 않고, 3-butenoic acid는 무수카르복실산 유도체로서 glutaric anhydride와 3-methylsuccinic anhydride 및 이중결합이 자리옮김된 crotonic acid가 얻어졌다.

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Synthesis of Poly(methacrylic acid)-functionalized SBA-15 and its Adsorption of Phenol in Aqueous Media

  • Vo, Vien;Kim, Hee-Jin;Kim, Ha-Yeong;Kim, Youngmee;Kim, Sung Jin
    • Bulletin of the Korean Chemical Society
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    • 제34권12호
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    • pp.3570-3576
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    • 2013
  • Poly(methacrylic acid)-functionalized SBA-15 silicas (denoted as P-x-PMA/SBA-15 where x is molar ratio of TSPM/(TEOS+TSPM) in percentage in the initial mixture) were synthesized by co-condensation of tetraethoxysilane and varying contents of 3-(trimethoxysilyl)propyl methacrylate in acidic medium with the block copolymer Pluronic 123 as a structure directing agent and then polymerization by methacrylic acid in the presence of ammonium persulfate as an initiator. The functionalized materials were characterized by PXRD, TEM, SEM, IR, and $N_2$ adsorption-desorption at 77 K. The investigation of phenol adsorption in aqueous solution on the materials showed that the poly(methacrylic acid)-functionalized mesoporous silicas possess strong adsorption ability for phenol with interaction of various kinds of hydrogen bonds. The adsorption data were fitted to Langmuir isotherms and the maximum adsorption capacity of the three functionalized materials P-5-PMA/SBA-15, P-10-PMA/SBA-15, and P-15-PMA/SBA-15 to be 129.37 mg/g, 187.97 mg/g, and 78.43 mg/g, respectively, were obtained. The effect of the pH on phenol adsorption was studied.

Radiation-Induced Graft Copolymerization of Methacrylic Acid and Methyl methacrylate onto Polyester.

  • Kang, Young-Kun;Chang, Hoon-Seun;Lee, Chong-Kwang;Park, Jae-Ho
    • Nuclear Engineering and Technology
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    • 제10권4호
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    • pp.195-201
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    • 1978
  • 감마선을 이용하여 폴리에스터직포에 methacylic acid와 methyl methacylate를 graft 종합반응시켜서 그 반응성을 보았다. 폴리에스터직포에 acrylic acid, methacrylic acid, methyl methacrylate를 중합반응 시켰을 때 graft 효율은 monomer 혼합용액내에 포함되어 있는 용매의 dielectric constant에 따라 상당한 차이를 나타내었다. Graft 수율은 방사선 선량과 monomer 농도 및 swelling agent의 농도에 좌우되었다. MA graft copolymer의 glass transition temperature (101$^{\circ}C$)와 melting point (238$^{\circ}C$)를 측정하였고, 정전기 효과는 frictional electricity 8,000V에서 half life가 0 sec이었으며, moisture regain는 5.6%, wicking time은 1 sec이었다.

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Evaluation of Physico-chemical Properties of Acrylic Resin Hydrogel and their Application to Transdermal Delivery System

  • Chung, Uoo-Tae;Choi, Seung-Man;Kang, Kee-Long;Kim, Nak-Seo;Chung, Youn-Bok
    • Archives of Pharmacal Research
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    • 제18권4호
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    • pp.224-230
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    • 1995
  • Recently, many attempts have been made to use hydrogels of various polymers as delivery systems of various drugs and bioactive materials to prolong and control their phamacological activities. In this study, we have evaluated the physico-chemical properties of methacrylic acid-methyacrylic acid methyl ester copolymer 9Eudispert mv)m a acrylic resin hydorgel, and its application to transdermal delivery system. In the dissolution tests, the release rate of salicylic acid (SA) and sodium salicylate (SOd. SA) were faster than lidocain (LD) and lidocain-HCl(LD-HCl). As the concentration of Eudispert mv polymer increased, the extensibility of Eudispert mu hydrogel decreased, whereas the swelling ratio increased. The more NaOH and polymer concentration increased, the more osmotic pressure linearly increased. The skin permeation of Sod. SA, an acidic model drug, was remarkably enhanced by Eudispert mv hydrogel. All fatty acids, except for Sod. glycolate, dramatically increased the skin permeation flux in Eudispert mu hydrogel containing LD-Hcl, a basic model drug. Consequently, it is suggested that Eudispert mv hydrogel may be used as potential transdermal delivery vehicle.

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분자각인 Poly(methacrylic acid)의 제조 및 레티노이드 화합물의 HPLC 분리 특성 (Preparation of Molecularly Imprinted Poly(methacrylic acid) and Its HPLC Separation Characteristics of Retinoids)

  • 남기훈;권영돈;김덕준
    • 폴리머
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    • 제26권6호
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    • pp.710-717
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    • 2002
  • 주형분자로서 all-trans-retinoic acid를 사용하여 methacrylic acid (MAA)를 가교 중합함으로써 분자각인고분자를 제조하였다 제조된 분자각인고분자가 충전된 HPLC컬럼의 분리특성을 살펴본 결과 레티노이드 유도체에 대해 좋은 분리 특성을 보였다. 주형분자의 양이 일정할 경우 주형분자대비 MAA의 양이 증가할수록 컬럼의 성능인자와 선택도는 높게 나타났으며, 이는 확률적으로 보다 많은 호스트분자와 주형분자간의 결합소를 제공한데 따른 결과이다. 유화중합에 의해 제조된 분자각인 고분자입자는 둥근 형태로 관찰되었으며 그 크기도 용액중합에 의해 제조된 것에 비해 훨씬 일정하게 분산되었으나, 분리특성은 효율이 떨어짐을 알 수 있었다 이러한 이유는 유화중합에 의한 분자각인고분자 제조시 물과 MAA 또는 물과 주형분자간의 수소결합에 의해 MAA와 주형분자간의 결합력 및 결합소의 수에 손실이 있었기 때문이다.