Abstract
The goal of this study was to broaden the spectrum of gas permeability and selectivity characteristics of poly(ethylene-co-acrylic acid) (EAA) by combining it with poly(ethylene oxide) (PEO), which has a high selectivity for CO 2. To obtain films that differed substantially in their solid state morphologies, EAA was combined with PEO as melt blends and as coextruded films with many alternating, continuous microlayers of EAA and PEO. The solid state structure and thermal behavior were characterized and the permeability to O 2 and CO2 was measured at 23°C. When the PEO was dispersed as small domains, the particles were too numerous for most of them to contain a heterogeneity that was sufficiently active to nucleate crystallization at the normal Tc The rubbery, amorphous nature of the PEO domains enhanced the gas permeability of the melt blends. In contrast, the constituent polymers maintained the bulk properties in 5-20 μ-thick microlayers. The series model accurately described the gas transport properties of microlayered films. Comparison of blends and microlayers revealed that the high CO 2 selectivity of PEO was most effectively captured when the PEO phase was continuous, as in the microlayers or in the cocontinuous 50/50 (wt/wt) melt blend.
Original language | English |
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Pages (from-to) | 1411-1419 |
Number of pages | 9 |
Journal | Journal of Applied Polymer Science |
Volume | 110 |
Issue number | 3 |
DOIs | |
Publication status | Published - 5 Nov 2008 |
Externally published | Yes |
Keywords
- Blends
- Carbon dioxide permeability
- Microlayers
- Oxygen permeability
- Polyethylene oxide