Oxygen transmission rates

FIGURE 2.11 Plot of oxygen transmission rate versus time for brominated poly(isobutylene-co-isoprene) (BIMS) nanocomposite. 

Pike, L., Measurement of Oxygen Transmission Rates of Film and Thin Sheeting Under Humid Conditions, TAPPI Proceedings, Polymers Laminations and Coatings Conference (1986). 

For the purification of the membranes, the common treatment with 0.1-2.0 N aqueous sodium/potassium hydroxide solutions has been compared with the purification of raw BC membranes using aqueous sodium/ potassium carbonate. Whereas hydroxide purification leads to a decrease of the tensile strength and an elongation of the material this effect is lower in the case of carbonate treatment. Moreover, the oxygen transmission rate is higher after carbonate washing. 

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. 

The water vapor and oxygen transmission rates of single films of va-... 

With the water content of the EvOH available from integration of eqn 1, the oxygen transmission rate of the package, OxTr, is calculated from ... 

The barrier performance of rigid containers was measured on both a second modified MOCON instrument and by a head space technique in which nitrogen purged and sealed containers were stored in an oxygen environment for periods of time. Containers were generally measured at 23°C with 100% relative humidity (RH) inside and either 50 or 75 RH outside. Container oxygen transmission rates (OTR) are expressed as cm30 /container-day-atm. 

The effect of orientation on oxygen permeability of the medium and high barrier resins is seen to be dependent upon the morphological nature of the barrier resin prior to orientation. A plot of the oxygen transmission rates as a function of the overall draw ratio (figure 3) illustrates this clearly. While the semicrystalline polymers, VDC copolymer, and aromatic nylon MXD-6, show little change in the permeability with moderate amounts of orientation in the solid state, orientation of the amorphous polymers SELAR PA 3426 and XHTA-50A causes reduction in the permeability by 5-30% in both resins, depending upon the overall level of orientation. 

Figure 3. Oxygen transmission rates as a function of the overall draw ratio, illustrating the dependence on the morphological nature of the barrier resin prior to orientation.

Variation of the oxygen transmission rate (cm day bar for 20 mm film) with relative humidity for the high barrier PVDC and EVAL films (from Plastics Engineering, May, 43, Soc. Plastics Eng. Inc., 1984). 

Polymer Film thickness (mm) Oxygen transmission rate (cm m day ) Water vapour transmission rate (gm day )... 

The oxygen transmission rates are high since these low crystallinity polymers are above Tg. The water vapour transmission rates are lowest for the metallocene PE of density 905 kg m. BS EN ISO 3826-1 2003 requires the water loss, when a full bag is stored for 42 days at 4 2 °C at 55% relative humidity, must be less than 2%. 

OTR oxygen transmission rate PASA polyamide-sulphonaniide... 

Bags produced with the same plasticizer but without benefit of this invention have an oxygen transmission rate of 12.9 at the same conditions as listed in the table. 

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]... 

Fig. 5.13 a Oxygen transmission rate (cm per per day) of PE, PHBV, and PE/PHBV blends (20 and 30 wt% PHBV). b PHBV distribution within the polymer matrix at different PHBV compositions and its effect on oxygen transmission rate [93]... 

Packaging film from plasticized PVCD has improved thermal stability and reduced stickiness to metal surfaces when only 2 wt% of epoxidized soybean oil is added as a plasticizer. In addition, the metal soaps of ricinoleie acid are added. They also act as plasticiz-ers. The addition of 1 to 4 wt% tetraethylene glycol di-(2-ethylhexoate) is expected to reduce oxygen transmission rates and to improve extrudability of film. ... 

Organic polymers as such cannot serve the necessary low oxygen transmission rates to ensure an acceptable lifetime. However, special tecimiques of deposition can reduce the gas transmission rates. 

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