Gas Permeability of E/EP Semicrystalline Diblock Copolymers

摘要

Gas permeability coefficients P for several gases (He. CO2, CH4, O2, N2) weremeasured at 25 deg C in a series of semicrystalline diblock copolymers of poly(ethylene)/ poly(ethylene-propylene) (E/EP). A simple model is presented describing the gas transport in these polymer systems. It predicts the permeability of a randomly oriented spherulitic diblock specimen from the permeabilities of the individual lamellar regions of the copolymer. Model predictions were in excellent agreement with the experimental data. The upper bound (lamellae aligned in parallel with respect to the permeation direction) and lower bound (series lamellar align models were calculated and compared to a limited amount of corresponding experimental data on oriented specimens.... Gas transport, Block copolymers, Semicrystalline polymers.