Preparation and characterization of multilayer film incorporating oxygen scavenger

The polymeric films (A-F types) as the practical approach of functional packaging to improve the quality and safety of products were developed and characterized concerning their optical, thermal, and mechanical properties. They were manufactured using a co-extrusion blow process for a three-layer structure with the core layer containing oxygen scavenging materials (OS1 or OS2) mixed with the HDPE or LLDPE. The % light transmission of the F film (LLDPE containing OS2) was much lower than that of the E film (LLDPE containing OS1) or LLDPE film (the control). The transparency of the F film was reduced dramatically due to the good dispersion of oxygen scavenger without agglomeration and the larger particle sizes than those of the E film, which can interrupt light transmission. The value of E film (25.6%), which indicates the percentage crystallinity, was lower than the F film (30.8%). Thermogravimetric analysis (TGA) of the film samples showed that the residual materials in the E and F films were approximately 7-9% above the value of the residue in the LLDPE film. Both E and F films showed lower values for the mechanical properties, such as the tensile & break strength and break elongation when compared with the LLDPE film. Selected multi-layer films incorporated with 20%, 30%, and 50% oxygen scavenging materials were also evaluated for their oxygen scavenging efficiency. The oxygen absorbing amounts of all E and F films increased at almost the same ratio as the oxygen scavenging material contents. The oxygen scavenging effect of the F film was slightly better than that of the E film, consuming 6.10 mL/O ₂ per g film after 30 days storage at 23 °C and 100% RH, because agglomeration in an E film resulted in a decrease in oxygen uptake. Therefore, a F film is preferred over other films for developing an efficient oxygen scavenging film.