Permeaiton of water and aqueous solute separation through block copolypeptide membrane which were composed by hydrophilic part and hydrophobic part were investigated. The block copolypeptides were synthesized by L-glutamic acid and L-leucine. Using p-phenylenediamine as an initiator, at first L-leucine NCA was polymerized homogeneously. Debenzylation of the obtained block s polymerized homogeneously, then γ-benzyl-L-glutamate NCA was polymerized homogeneously. Debenzylation of the obtained block copolypeptides were carried out with 33% HBr/AcOH solution. Poly-L-leucine-L-glutamate (PLG) membrane and debenzylated poly-L-leucine-L-glutamate (d-PLG) membrane were prepared by dissolving polymers in benzene and DMF, respectively. Water flux (J_w) and hydraulic permeability (K_w) of d-PLG membrane which have a hydrophilic group with in side chain were significantly improved compared with those of PLG membrane. From the result of water soluble alcohols separation, the amount of separated solute decreased with increasing Taft number (σ^*) and acidity (ΔV_s) of alcohols. The solute separation abllity of d-PLG membrane was better than that of PLG membrane. The critical surface tension of PLG and d-PLG membrane were 27(dyne/cm) and 34(dyne/cm), respectively.

친수성부분과 소수성부분을 블록구조로 갖는 펩티드막의 투수성 및 수용성용질의 분리성능을 검토하였다. p-phenylenediamine을 개시제로 L-leucine N-carboxyanhydride (NCA)를 1차 중합시킨 후 중합된 폴리머에 γ-benzyl-L-g1utamate (γ-BLG) NCA를 2차 중합시켜 block copolypeptide를 얻었으며 이 block copolypeptide를 33% HBr/Acetic acid (AcOH) 용액으로 debenzylation하여 축쇄에 친수성기(-COOH)를 도입하였다. Poly-L-leucine-L-glutamate(PLG)의 3% 벤젠용액과 debenzylated poly-L-leucine-L-glutamate(d-PLG)의 3% 디메틸프롬아미드용액을 각각 유리판에 유정하여 제조하였다. 투수성을 측정한 결과 water flux, J_w 및 hydraulic permeability, K_w는 투과온도와 투과압력이 높아짐에 따라 증가하였으며 PLG막에 비해 친수성기인 -COOH기가 도입된 d-PLG막의 J_w 및 K_w가 더 증가하였다. 수용성용질의 분리실험결과 알코올의 Taft number(σ^*) 및 acidity(ΔV_s)가 커짐에 따라 용질배제율은 감소하였으며 PLG막에 비해 극성기인 -COOH기가 도입된 d-PLG막의 용질배제성이 더 큼을 알 수 있었다. 한편, 임계표면장력은 PLG가 27 dyne/cm, d-PLG가 34 dyne/cm이었다.

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