The oxygen permeation characteristics of for ester type polyurethane(PU) and poly(urethane-g-propylene sulfide)(PU-g-S) membranes were studied under different permeation conditions. PU-g-S was prepared by anionic graft polymerization. PU was dissolved in dehydrated DMF and NaH was added under nitrogen atmosphere at 0℃. Hydrogens of urethane bonds were substituted by Na⁺ ions. Diffusion coefficients were obtained from time-lag method. Diffusion and permeation coefficients were increased with increase in temperature of permeation and were independent of pressure. Diffusion coefficient of PU-g-S membrane was 10 times larger than that of PU membrane. Permeability coefficient of PU-g-S membrane for O₂ was 8.8×10^-10(cm³(STP)·cm/cm²·sec·.cmHg) at 60℃, 300 psi and was 3.7×10^-10(cm³(STP)·cm/cm²·sec·cmHg) for N₂. Therefore, it was found that PU-g-S membrane had good permselectivity for O₂. Grafted copolymer was confirmed by IR and elementary analysis and permeation characteristics were studied in transition temperature by DSC.

에스테르형 폴리우레탄(PU)막과 propylene sulfide를 그라프트시킨 폴리우레탄(PU-g-S)막을 이용하여 산소투과특성을 검토하였다. 폴리우레탄을 DMF에 녹인후 0℃에서 sodium hydride를 사용하여 우레탄결합중의 수소를 Na로 치환시킨 후 음이온중합으로 propylene sulfide를 그라프트시켰다. 확산계수는 time-lag법으로 구했으며 온도상승에 비례하여 확산계수와 투과계수가 증가했으며 압력의존성은 없었다. PU-g-S막의 확산계수는 PU막보다 10배정도 컸으며 산소와 질소의 투과계수는 각각 8.8×10^-10(cm³(STP)·cm/cm²·sec·cmHg)과 3.7×10^-10(cm³(STP)·cm/cm²·sec·cmHg)으로 산소의 투과계수가 질소의 투과계수보다 3배정도 컸다. 이상의 결과로부터 propylene sulfide가 그라프트된 PU-g-S막 산소에 대한 선택투과성이 좋음을 알았다. 한편, 그라프트공중합체를 IR과 원소분석으로 분석하였다. 또 DSC로 전이영역에서의 투과특성을 고찰하였다.

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