Oxygen permeability, various

Moyssiadi T, Badeka A, Kondyli E, Vakirtzi T, Savvaidis I and Kontominas M G (2004), Effect of light transmittance and oxygen permeability of various packaging materials on keeping quality of low fat pasteurized milk chemical and sensorial aspects , International Dairy Journal, 14, 429 -36. 

Table 7.3. Relative Fluorescence Quantum Yield of Crystal Violet,

Abstract Pressure-sensitive paint (PSP) is applied to the areodynamics measurement. PSP is optical sensor based on the luminescence of dye probe molecules quenching by oxygen gas. Many PSPs are composed of probe dye molecules, such as polycyclic aromatic hydrocarbons (pyrene, pyrene derivative etc.), transition metal complexes (ruthenium(II), osumium(II), iridium(III) etc.), and metalloporphyrins (platinum (II), palladium(II), etc.) immobilized in oxygen permeable polymer (silicone, polystyrene, fluorinated polymer, cellulose derivative, etc.) film. Dye probe molecules adsorbed layer based PSPs such as pyrene derivative and porphyrins directly adsorbed onto anodic oxidised aluminium plat substrate also developed. In this section the properties of various oxygen permeable polymer for matrix and various dye probes for PSP are described. 

Many PSPs are composed of probe dyes, such as polycyclic aromatic hydrocarbons (e.g., pyrene) and coordination compounds (e.g., platinum por-phryins and ruthenium(II) polypyridyl complexes) immobilized in various gas permeable polymer films such as silicon polymer, organic glassy polymers (e.g., poly(methylmethacrylate), polystyrene), fluorinated polymers, or cellulose derivatives such as ethyl cellulose [9,10]. As probe molecules interact with polymer matrices directly, the properties of PSPs strongly depend on the properties of polymer matrices. The oxygen permeability of polymer matrix is an especially important factor for highly sensitive PSP. 

Finally, PSPs based on the OEP metal complexes in various cellulose derivative polymers also have been introduced. Cellulose derivative polymers such as ethyl cellulose, cellulose acetate etc., as shown in Fig. 9, also provide a mechanical strength to thin film. The oxygen permeability, diffusion constant, and solubility for oxygen for typical cellulose derivative polymers are listed in Table 1. Cellulose derivative polymer films with plasticizer tributyl phosphate (TBP) have large oxygen permeability. Cellulose acetate with TBP... 

P. H. List, G. Kaosio, Water vapor and oxygen permeability of various tablet coatings, Acta Pharm Techn 28(1) 1982. 

Figure4.3 Oxygen permeability coefficients of poly (2,6-dimethyl-1,4-phenylene oxide) (PPO) films of various thicknesses, as a function of aging time at 35 °C [52], Reproduced with permission of the American Chemical Society.

In addition to these materials, several others, such as polyurethanes, polysulfones, polyvinyl alcohol, and various copolymers, have been tried or are under development. Recently, silicon hydrogel lenses with high oxygen permeability were marketed. The future... 

Effect Of Molecular Structure on Polycarbonate Oxygen Permeability. Permeability measurements on a series of structurally different aromatic polycarbonates indicate a strong relationship between monomer structure and polymer permeability. A major part of this study investigated properties of polycarbonates which were prepared from variously substituted bisphenols. The polycarbonate samples are based upon bisphenol monomers which differ from 2,2-bis(4-hydroxy-... 

Figure 3 Demonstration of the dramatic reductions in oxygen permeability at 25°C following surface sulfonation to different degrees. The effects of introducing different ions in place of the NH4+ is also illustrated. The oxygen permeabilities of various resins are shown for comparison.

Table I. Oxygen Permeability in Polymers of Various Molecular Structures at 25 °C...

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