The permeation characteristics of CO₂, O₂ and N₂ through polyester membranes made from solvent-crystallized/PET and the blends of PET with amorphous poly(diethyleneglycol) terephthalate [P(DEG)] were studied under different permeation conditions. Membranes were prepd. by dissolving polymers in a mixed-solvent tetrachlorethane (TCE)-phenol (40 : 60 wt%) and casting them on the glass plate. The crystallization of undrawn amorphous polyester membranes was carried out by treating with electron-donating benzene solvent and electron-accepting benzyl alcohol solvent at -10℃∼50℃ for 4hours. The changes of conformation following crystallization were studied by density and infrared-spectroscopy. From the data of permeability measurements, it was found that the permeability coefficients of gases were increased with the increase in the content of P(DEG)T in the blends and in order CO₂ > O₂ > N₂ but decreased with the increase in the degree of crystallinity. The diffusion coefficients were increased in order O₂ > N₂ > CO₂ and then, the effect of crystallinity to permeation was illustrated by using conception of τ,β.

폴리에스테르막의 기체투과특성을 검토하기 위하여 polyethyleneterephthalate(PET)막과 비결정질인 poly(diethylene glycol)terephthalate[P(DEG)T]를 PET와 혼합하여 제조한 막으로 CO₂, O₂ 및 N₂의 단일기체에 대한 투과특성을 검토하였다. 중합체는 Tetrachloroethane(TCE)-Phenol(40 : 60wt%)의 혼합용매에 녹여 막을 제조한 후 막의 용매처리는 미연신 비결정성막을 전자공여성용매인 벤젠과 전자수용성용매인 벤질알코올 용매중에서 각각 -10℃∼50℃로 처리하여 결정성을 부여하였다. 용매처리에 의한 막의 결정화도와 구조변화는 밀도와 적외선분광광도계를 사용하여 검토하였다. 실험결과 폴리에스테르막의 기체투과계수는 CO₂ > O₂ N₂ 순이며 확산계수는 O₂ > N₂ > CO₂ 순임을 알 수 있었으며 P(DEG)T의 함량이 증가함에 따라 확산계수 및 투과계수는 증가하였다. 폴리에스테르 막내의 기체투과는 viscous flow가 아니며 결정화도가 증가됨에 따라 기체의 투과는 직선적으로 감소하였다. 또한 결정화도가 투과의 미치는 영향을 τ 및 β값으로 설명하였다.

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