Barrier properties oxygen transmission rate

Gas barrier properties - Metabolix PHA polymers have lower moisture vapour transmission rates than other biodegradable polymers. The oxygen transmission rates for unoriented PHA films are 25-30 cc-mil/(100 in2-day) at 77 °C, 0% relative humidity. 

Barrier Properties Exact Plastomers create controllable gas-permeable films for modified atmospheres, as well as gas-permeable films and packaging for such items as fresh vegetables, fhiits, flowers, and a growing range of other horticultural products. Users can select carbon dioxide and oxygen transmission rates (OTR) that meet their needs, with low water vapor transmission rates (WVTR) and high levels of clarity and gloss. " ... 

Honeywell Oxy Shield nylon/EVOH oxygen-barrier (OB) film s combination of nylon 6 and EVOH delivers a strong mix of benefits the strength, toughness, and flex-crack resistance of nylon with the extremely low oxygen transmission rates, superior fla-vor/odor/aroma-barrier properties, with the outstanding solvent and oil resistance of both nylon and EVOH. The film is microwaveable and recyclable, and does not release harmful substances upon incineration.do 3]... 

Cerrada [97] has examined the gas barrier properties of food-grade ethylene-vinyl alcohol copolymers used in film and bottle manufacturing as a function of the ethylene and vinyl alcohol content. Oxygen transmission rates have been reported for polyolefin nanocomposites [98]. 

The CNCs improve the barrier properties like oxygen transmission rate (OTR) and water vapor transmission rate (WVTR) as well as mechanical properties like young s modulus and strength of PLA matrix (Okastnan et al., 2006). 

Figure 21.14 reports the effect of Nanomer I.24TL loading on the oxygen transmission rate of polyamide 6. Around 80% improvement in oxygen barrier properties is obtained for nanocomposites containing 8 wt% organoclay [60]. 

Figure 7 shows the oxygen barrier properties as a function of the number of clay-PAM bilayers on a PET substrate. The oxygen transmission rate (OTR) and permeability decrease by an order of magnitude between 10 and 15 bilayers. The permeability of a 20-bilayer... 

The coated container side has no influence on the barrier effect itself (Figure 2), as long as no interactions of the coating and the permeating molecules exist and the surface properties are identical. The picture shows for the oxygen transmission rate (OTR) that there is no influence of the direction of permeation. The IKV conducted measurements with barrier coated 12 [tm PET-foils, which underlined that (Table 1). The variance of the OTR lies in the range of the standard deviation. 

Certain copolymers of this type have been found to have excellent gas barrier properties, with the dry polymer having an oxygen permeability only about 1/lOth that of polyvinylidene chloride. Unsurprisingly, the copolymer has a high moisture absorption and a high moisture vapour transmission rate. Where the material is swollen by water, gas permeability is also higher. 

The barrier properties of starch nanocrystals/natural rubber nanocomposites were also investigated [39]. For these systems, the water vapour transmission rate, the diffusion coefficient of oxygen, the permeability coefficient of oxygen and its solubility, were measured. It was observed that the permeabiUty to water vapour, as well as to oxygen, decreased when starch nanocrystals wctc added These effects were ascribed to the platelet-like morphology of the nanocrystals. 

As the mol ratio moves in the direction of PVOH, the properties become more like those of PVCW. Moisture vapor transmission rate (MVTE) and moisture sensitivity increase, specific gravity increases, melting point increases, and processing sensitivity increases. Oxygen barrier increases, gas transmission decreases and stiffness goes up. 

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