温度对聚氧乙烯/共聚酯型聚氨酯共混物气体渗透行为影响的研究

Effect of Temperature on Gas Permeation of Poly (Ethylene Oxide)/Copolyester-Polyurethane Blends

在20°～80℃范围内的一系列温度下研究了H_2、N_2、O_2和CO_2气体对聚氧乙烯(PEO)/共聚酯型聚氨酯(PU)共混物的渗透行为。共混物透气系数的对数对温度的倒数作图符合Arrhenius关系,但在共混物中PEO熔点附近会出现转折点或突变;在PEO熔点上下,共混物有着完全不同的透气系数—组成曲线以及气体渗透活化能—组成曲线。结果说明了温度强烈影响共混物的气体渗透行为。

The transport behavior of H_2, N_2, O_2and CO_2was studied for blends of poly(ethylene oxide) (PEO) with a copolyester-polyurethane (PU) at various temperaturesfrom 20 to 80℃. It was found that there was an abrupt change in slope or a gap aroundthe melting point of PEO in Arrhenius plot of the permeability vs. temperature. The rela-tionships between the logarithm of gas permeability and blend composition were stronglydependent on the temperature and showed very different shapes at temperature belowand above the melting point of PEO. The activation energy of gas permeation for theblends had different values below and above the melting temperature of PEO.