Barrier, mechanical, and thermal properties of the three-layered co-extruded blown polyethylene/ethylene–vinyl alcohol/low density polyethylene film without tie layers

Abstract

This article investigates three-layer co-extruded blown film comprised of low-density polyethylene (LDPE)/ethylene–vinyl alcohol (EVOH)/LDPE without adhesion layers. Various thicknesses of pure EVOH were sandwiched by outer LDPE layers blended with linear low-density polyethylene-grafted-maleic anhydride (LLDPE- g-MAH) as compatibilizer in concentrations from 0 wt% to 2.0 wt%. The study found that a mere 3-μ EVOH layer can achieve a 180 times improvement of oxygen barrier properties as compared to the control sample. When the EVOH loading is 10–15 wt% of the total film mass, the addition of LLDPE- g-MAH into the outer layers indicated a positive synergistic effect by enhancing barrier properties. In contrast, when the EVOH loadings are at 5 wt% and 7.5 wt%, the barrier properties of the film was reduced. Layer-to-layer interaction between the LDPE and EVOH was notably improved as demonstrated by a 26–42% increase of interlaminate peel strength in the presence of 0.5–2 wt% LLDPE- g-MAH in all samples. Congruently, the introduction of the LLDPE- g-MAH into the outer LDPE layers also resulted in an increased dart impact toughness and tensile strength for the film. The EVOH crystallinity showed a reduction after adding LLDPE- g-MAH, particularly apparent for the lower EVOH concentrations.

In Situ Observation of Chemical Reactions at Buried Solid/Solid Interfaces in Coextruded Multilayer Polymer Films

“…However, it can be challenging for these dissimilar polymer layers to adhere adequately, and interfacial delamination may lead to loss of package integrity. – To improve the adhesion between these incompatible polymers, extrudable “Tie” resins have been developed in order to enable the successful production of coextruded polyolefin and barrier layer films. The Tie resin is typically miscible with the polyolefin layer and is thought to form a covalent linkage with the polar barrier layer to improve adhesion and prevent delamination. – Such coextruded multilayer barrier films can provide highly efficient packaging schemes for extending shelf life and protecting food safety and are extensively applied in high-value food packaging applications such as meat and cheese. It has become increasingly important to understand the molecular-level interactions at polymer–polymer and polymer-Tie interfaces to develop next-generation Tie resins to enable the design of more recyclable high-performance barrier packaging.…”

Evaluating Effectiveness of Multi-Component Waste Plastic Bags on Bitumen Properties: Physical, Rheological, and Aging

“…Moreover, various organic and inorganic additives may be integrated into the polymer matrix, depending on the intended application, such as optimizing the properties of the final product or reducing production costs [ 26 ]. Considering plastic bags, for instance, which represent one of the most used types of plastic materials, with a consumption of around 500 billion plastic bags yearly worldwide [ 27 ], they typically consist of a blend of multiple plastics and include organic and inorganic additives [ 28 ]. Upon disposal, recycling processes encounter difficulties in fully segregating and recycling the diverse components of these products [ 29 , 30 , 31 ], resulting in their accumulation in landfills [ 4 , 32 ].…”

A novel method for industrial manufacturing of thermoplastic multilayer films: Processing, microstructure, and properties

“…Multilayer films feature various applications ranging from food packaging to optical elements and sensors . Multilayer coextrusion blowing technique, which can take advantage of desirable component properties, such as high strength, thermoformability, and barrier properties, becomes one of the most widely applied manufacturing methods for multilayer film fabrication.…”