Influence of the hottest microwave treatment on th

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Effect of microwave treatment on the barrier property of plastic film packaging material III

Figure 2 and figure 3 show the influence curve of microwave treatment time on the oxygen permeability of composite film. It can be seen from the figure that although the oxygen permeability of the composite plastic film is very small, the transmittance decreases with the increase of microwave treatment time; The effect of microwave treatment on the oxygen permeability of double-layer composite membrane is more obvious than that of three-layer composite membrane

2.2 effect of microwave treatment on the moisture permeability of plastic film packaging materials

when different packaging materials are treated with microwave for a certain time, we will also see a batch of small and medium-sized potential enterprises active in the analytical instrument industry, and then measure their moisture permeability. The results are shown in Table 4

the variation law of moisture permeability in Table 4 is shown in Figure 4. It can be seen from the figure that the moisture permeability of all packaging materials increases with the increase of microwave treatment time. However, the average growth rate of moisture permeability is different from that of oxygen permeability. The growth rate of single film is low, which is no more than 5% per minute, while the growth rate of double-layer and three-layer composite films on the transmission is up to more than 10%. However, the increase of absolute value of moisture permeability is still greater for single film

3 conclusion

after microwave treatment, the oxygen permeability and moisture permeability of both single and composite membranes will increase, and their barrier properties will decrease; After microwave heating for 1 min, the barrier performance decreased by about 3% - 15%. Therefore, before using the puncture device, the processing time should not be too long for the food stored after microwave sterilization after packaging, otherwise it will affect the barrier performance of packaging materials and the shelf life of goods

source: Packaging Engineering

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