Polymers to gases

The permeabUity of ceUular polymers to gases and vapors depends on the fraction of open ceUs as weU as the polymer-phase composition and state. The presence of open ceUs in a foam allows gases and vapors to permeate the ceU stmcture by diffusion and convection dow, yielding very large permeation rates. In closed-ceUed foams the permeation of gases or vapors is governed by composition of the polymer phase, gas composition, density, and ceUular stmcture of the foam (194,199,215,218,219). 

Permeability of Polymers to Gases and Vapors Brochure P302-335-79, The Dow Chemical Company, Midland, Mich., 1979. 

Stern SA, Krishnakumar B and Nadakatti SM, "Permeability of Polymers to Gases and Vapours", in Mark JE (Ed), "Physical Properties of Polymers Handbook", AIP Press, Woodbury, NY, 1996, Chap. 50. 

Permeability of Polymers to Gases, Vapors, and Liquids, Alexander Leborits, Modern... 

The permeability of a crystalline polymer to gases depends on its crystallinity index and degree of order. These depend on processing conditions, so the preparation conditions and thermal history of the samples to be measured must be clearly stated. 1... 

TABLE 61.12. Polyurethanes. PERMEABtLITY OF POLYMERS TO GASES AND VAPORS / 1043... 

The permeability of cellular polymers to gases and vapors depends on the fraction of open cells as well as the polymer-phase composition and state. The... 

Table 15.3 Permeability coefficients of selected polymers to gases...

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