Influence of high-pressure processing on morphological, thermal and mechanical properties of retort and metallized flexible packaging

The effect of high-pressure processing on the morphological, thermal and mechanical properties of flexible packages was evaluated. The packages were composed of PET/Al/PA/PP (sample A) and PET/printing/metallization/PET/LDPE-coex (sample B), were processed under three different conditions (600 MPa/25 °C for 10 min, 600 MPa/90 °C for 10 min and 0.1 MPa/90 °C for 10 min), with an unprocessed sample being used as a control. Sample A showed visual and microscopic defects after processing at 600 MPa/90 °C in 20% of the processed packages, and the melting temperature of the PA layer was significantly lower (p