• Title, Summary, Keyword: poly(ethylene oxide)

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Synthesis of New pH-Sensitive Poly(ethylene oxide-b-maleic acid) from Modification of Poly(ethylene oxide-b-N-phenylmaleimide)

  • Go, Da-Hyeon;Jeon, Hee-Jeong;Kim, Tae-Hwan;Kim, Geun-Seok;Choi, Jin-Hee;Lee, Jae-Yeol;Kim, Jung-Ahn;Yoo, Hyun-Oh;Bae, You-Han
    • Macromolecular Research
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    • v.16 no.7
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    • pp.659-662
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    • 2008
  • A new and useful poly(ethylene oxide)-based pH-sensitive block copolymer is introduced. Poly(ethylene oxide-b-N-phenylmaleimide) was first synthesized by anionic polymerization of N-phenylmaleimide (N-PMI) using mixed alkali metal polymeric alkoxide by sequential monomer addition method in the mixture of benzene/THF/DMSO (10/5/3, v/v/v) at room temperature. Reductive deimidation of the resulting block copolymer was performed using hydrazine monohydrate leading to the formation of the corresponding pH-sensitive poly(ethylene oxide-b-maleic acid).

Release of Cytarabine from $Poly({\varepsilon}-carbobenzoxy\;L-lysine)$/Poly(ethylene oxide)/Poly({\varepsilon}-carbobenzoxy\;L-lysine)$ Block Copolymer Microspheres ($Poly({\varepsilon}-carbobenzoxy\;L-lysine)$/Poly(ethylene oxide)/$Poly({\varepsilon}-carbobenzoxy\;L-lysine)$ 블록 공중합체 미립자에서 Cytarabine의 방출특성)

  • Cho, Chong-Su;Kwon, Joong-Kuen;Jo, Byung-Wook;Lee, Kang-Choon;Sung, Yong-Kiel
    • Journal of Pharmaceutical Investigation
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    • v.22 no.4
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    • pp.323-326
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    • 1992
  • $Poly({\varepsilon}-carbobenzoxy\;L-lysine)/poly(ethylene oxide)/poly({\varepsilon}-carbobenzoxy\;L-lysine)$ (LEL) block copolymers containing $poly({\varepsilon}-carbobenzoxy\;L-lysine)$ (PCLL) as the A component and poly(ethylene oxide) (PEO) as the B component were investigated as drug delivery matrix. PCLL homopolymer and LEL block copolymer microspheres containing anticancer drug, cytarabine, were prepared by a solvent evaporation process and the release patterns of cytarabine from the microspheres were investigated in vitro. The size of PCLL homopolymer and LEL block copolymer microspheres was ranged from $0.2\;{\mu}m$ to $1\;{\mu}m$ in diameter and the shape of the microspheres was almost round. The release pattern of cytarabine from the block copolymer microspheres was dependent on the mole % of PEO of the block copolymers.

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Preparation and Characterization of Poly$({\gamma}-benzyl\;L-glutamate)$/Poly(ethylene oxide)-Lactoselactone Block Copolymers and Their Microspheres (Poly$({\gamma}-benzyl\;L-glutamate)$/Poly(ethylene oxide)-Lactoselactone 블록공중합체와 이들의 미립자 제조 및 특성)

  • Kim, Young-Hoon;Cho, Chong-Su;Sung, Young-Kiel;Chung, Byung-Ho;Lee, Kang-Choon
    • Journal of Pharmaceutical Investigation
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    • v.22 no.3
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    • pp.237-240
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    • 1992
  • A series of biodegradable block copolymers consisting of $poly({\gamma}-benzyl\;L-glutamate)$ (PBLG) and poly(ethylene oxide) (PEO)-lactoselactone were prepared by polymerization of PEO-lactoselactone and ${\gamma}-benzyl$ L-glutamate-N-carboxyanhydride and characterized by IR and NMR. From circular dichroism measurements, it was found that the polymers exist in the ${\alpha}-helical$ conformation. Block copolymer microspheres were prepared by solvent-extraction-precipitation method for their primary evaluation for medical and biological applications.

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Synthesis of Biodegradable Polymers with Carbon Dioixde (이산화탄소를 이용한 생분해성 고분자의 합성)

  • Shin Sang Chul;Shin Jae Shik;Lee Yoon Rae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.5 no.6
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    • pp.521-525
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    • 2004
  • Biodegradation of poly(ethylene carbonate) (PEC) and their terpolymers has been investigated in vitro. PEC has been synthesized with ethylene oxide (EO) and carbon dioxide, which is one of the greenhouse gases using Zinc glutarate has been used as catalyst Carbonate terpolymers have been prepared by the use of EO, cyclohexene oxide(CHO), and carbon dioxide. High biodegradability of PEC and terpolymers with EO. has been observed. Very low biodegradation of poly(propylene carbonate) (PPC) and poly(cyclohexene carbonate) (PCHC) has been shown. The weight loss, FT-IR and SEM have been employed to characterize biodegradability.

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Biodegradability of $Poly({\gamma}-benzyl{\;}L-Glutamate)/Poly(Ethylene Oxide)/poly({\gamma}-benzyl{\;}L-Glutamate)$ Block Copolymer in Mice

  • Oh, In-joon;Oh, Jhin-Yee;Cho, Chong-Su;Lee, Kang-Choon
    • Archives of Pharmacal Research
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    • v.18 no.1
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    • pp.8-11
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    • 1995
  • Biodegradability of poly $Poly({\gamma}-benzyl L-Glutamate)/poly(ethylene oxide)/Poly({\gamma}-benzyl L-Glutamate)$ block copolymer (GEG) having different content of poly(ethylene oxide) (PEO) were examined using magnetite as a tracer in mice. GEG microspheres containing magnetite were injected into mice through tail vein. Biodegradability and tissue distribution of microspheres were examined by analyzing the amount of magnetite in the microspheres recollected from mice organs after specific time interval. The results showed that GEG microsphere of high content of PEO was degraded more rapidly than those of low content of PEO in the mice organs.

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Preparation and Characterization of Elastomeric Solid Electrolyte Based on $PEO-EDA-LiClO_4$ Blends ($PEO-EDA-LiClO_4$ 블렌드계 탄성체 전해질의 제조와 특성)

  • Chang, Young-Wook;Joo, Hyun-Seok
    • Elastomers and Composites
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    • v.39 no.1
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    • pp.36-41
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    • 2004
  • Solid polymer electrolytes were prepared by UV irradiation of the blends consisting of poly(ethylene oxide)(PEO), epoxy diacrylate(EDA) and LiClO_4$. Conductivities of the electrolyte films were measured as a function or blend composition, salt concentration and temperature. The electrolyte having the composition of poly(ethylene oxide) (70% by weight)/epoxy diacrylate (30% by weight) with mole ratio of 10 of ethylene $oxide/Li^+$ exhibited a high ionic conductivity of $1.2{\times}10^{-5} S/cm$ at $25^{\circ}C$. This blend is transparent and shows elastomeric properties. Morphological studies by means of differential scanning calorimetry, X-ray diffraction and polarized optical microscopy indicated that the cured epoxy chains in the blends inhibit the crystallization of poly (ethylene oxide) and thereby induce the blend systems to be completely amorphous in certain compositions.

Kinetics of Isothermal Crystallization in Poly(ethylene oxide) and Poly(styrene-co-acrylic acid)Blends (Poly(ethylene oxide)/Poly(styrene-co-acrylic acid) Blends의 등온 결정화 속도에 관한 연구)

  • Lee, Sang-Cheol;Lee, Mu-Seong;Jo, Won-Ho
    • Korean Journal of Materials Research
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    • v.1 no.3
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    • pp.151-155
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    • 1991
  • The kinetics of isothermal crystallization in blends of poly(ethylene oxide) (PEO) and poly(styrene-co-acrylic acid) (SAA) has been examined as a function of the blend ratio, the copolymer composition, and the crystallization temperature, based on the Avrami eauation. The Avrami exponents were mostly chose to 2, independent of the crystallization temperature. The crystallization rate of PEO in PEO/SAA blends decreased with the increase of SAA content. And also, the higher the acrylic acid content in the SAA copolymer, 7he slower the crystallization rate of PEO in the blends.

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Synthesis and Properties of Block Copolymer Comprising of Poly(DL-lactic acid) and Poly(ethylene oxide) (Poly(DL-lactic acid)/Poly(ethylene oxide)을 포함한 블록공중합체의 합성 및 특성)

  • 이찬우;배기서
    • Polymer(Korea)
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    • v.26 no.5
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    • pp.582-588
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    • 2002
  • The block copolymers were prepared by the ring opening polymerizati on of DL-lactide by poly(ethylene oxide) (PEO) with diethylzinc (ZnE$_2$) as a catalyst. When the feed ratio of PEO was over 30% relative to DL-lactide, the polymerization of DL-lactide took place from the PEO hydroxyl terminals to provide the desired A -B-A or A-B block copolymer. The block copolymers were made of films by cast method and the films obtained was drawn to 2.5 times at 60 $\^{C}$. At the same draw ratio, the tensile modulus of the films was decreased with increasing PEO content in the block copolymers. It was therefore suggested that the block copolymers comprising of PDLLA and PEO, had high potentials as the biomaterials with improved flexibility.