Article
  • Effect of Poly(ethylene oxide) on the Cloud Point of Poly(N-isopropyl acrylamide-co-acrylic acid) in Aqueous Solution
  • Lee JH, Yoo MK, Cho CS, Sung YK
  • 수용액중에 Poly(N-isopropyl acrylamide-co-acrylic acid)의 담점에 미치는 Poly(ethylene oxide)의 영향에 관한 연구
  • 이진희, 유미경, 조종수, 성용길
Abstract
Temperature/pH sensitive copolymers were synthesized by free radical polymerization of N-isopropyl acrylamide(NIPAAm) and acrylic acid (AAc) in dioxane using 2,2-azobisisobutyronitrile (AIBN) as an initiator. The poly(N-isopropyl acrylamide-co-acrylic acid)s[poly(NIPAAm-co-AAc)s] were prepared by varying molar percentage of AAc in the copolymers. The influence of inter-and intra-hydrogen bonding on the clound points(CPs) of aqueous poly(NPAAm-co-AAc) solution was investigated in the pH range of 2.0∼7.4, making use of poly(ethylene oxide) (PEO). The molecular weights of used P대 were 4 × 102, 6 × 103, 1 × 105, 1 × 106, respectively, and the CPs were determined by UV/visible spectrophotometry. The CPs of the aqueous poly(NIPAAm-co-AAc) solutions were affected by pH, AAc content, and molecular weight of PEO. At pH 4.0, CP of the copolymer containing PEO(M.W.: 1 × 106)was higher than those of the copolymer itself due to intermolecular hydrogen bonding between PAAc and PEO.

온도/pH 감응성 공중합체인 poly(N-isopropyl acrylamide-co-acrylic acid)[poly(NP-AAm-co-AAc)]를 단량체 N-isopropyl acrylamide (NIPAAm)과 acrylic acid(AAc), 개시제 2,2-azobisiobutyronitril (AIBN)를 사용하여 dioxane 용매 속에서 라디칼 중합에 의해 합성 하였다. 이때 공중합체 내 AAc의 성분이 10, 20, 30, 40, 50 mol%가 되도록 합성하여Trhm 수용액상에서 poly(NIPAAm-co-AAc)의 담점 (cloud point, CP)에 미치는 분자내 또는 분자간 수소결합의 영향을 poly(ethylene oxide) (PEO)를 선택하여 pH 2.0-7.4의 범위에서 조사하였다. PEO의 분자량은 4 × 102, 6 × 103, 1 × 104, 1 × 105, 1 × 106인 것을 선택하여 사용하였고 담점은 자외선 분광광도측정접을 이용하여 측정하였다. 수용액상에서 poly(NIPAAm-co-AAc)의 담점은 pH, 공중합체 중의 AAc 함량, PEO의 분자량에 큰 영향을 받았다. 또한, pH 2.0, 3.0, 5.0, 7.4에서는 PEO의 첨가가 poly(NIPAAm-co-AAc)수용액의 담점에 큰 영향을 미치지 않았으나 pH 4.0DPTJSMS PEO (M.W : 1 × 106)가 첨가된 poly(NIPAAm-co-AAc) 수용액의 담점은 PAAc와 PEO 사이의 분자간 수소결합에 의해 PEO가 첨가되지 않은 경우보다 온도에서 나타났다.

Keywords: temperature/pH sensitive polymer; inter-and intramolecular hydrogen bondings; cloud point; lower critical solution temperature(LCST)

  • Polymer(Korea) 폴리머
  • Frequency : Bimonthly(odd)
    ISSN 0379-153X(Print)
    ISSN 2234-8077(Online)
    Abbr. Polym. Korea
  • 2022 Impact Factor : 0.4
  • Indexed in SCIE

This Article

  • 1999; 23(5): 755-762

    Published online Sep 25, 1999

  • 10.7317/pk.
  • Received on Nov 30, -0001
  • Revised on Nov 30, -0001
  • Accepted on Nov 30, -0001

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