CO2 permeation and diffusion properties of semicrystalline poly(4-methyl pentene-1) membranes

CO2 permeation and diffusion behaviors of poly(4-methyl pentene-l) (PMP) wi th three different degrees of crystallinity were examined at -10 to 45 degr ees C. Permeation and diffusion coefficients in crystalline and amorphous p arts of PMP were obtained by an extrapolation to 100 and 0% degrees of crys tallinity, respectively. The inflection corresponding to the glass transiti on temperature of PMP was observed in Arrhenius plot of both the permeabili ty and diffusion coefficients only for the amorphous part of PMP. The non z ero values of permeation and diffusion coefficients of crystalline part of PMP indicated that the permeation and diffusion of CO2 occurred even in the crystalline part of PMP. The permeation and diffusion of CO2 for the cryst alline part of PMP were Arrhenius type within experimental scatter.