Closing the loop on plastic packaging materials: What is quality and how does it affect their circularity?

Many plastic packaging materials manufactured today are composites made of distinct polymer layers (i.e., multilayer films). Billions of pounds of these multilayer films are produced annually, but manufacturing inefficiencies result in large, corresponding postindustrial waste streams. Although relatively clean (as opposed to municipal wastes) and of near-constant composition, no commercially practiced technologies exist to fully deconstruct postindustrial multilayer film wastes into pure, recyclable polymers. Here, we demonstrate a unique strategy we call solvent-targeted recovery and precipitation (STRAP) to deconstruct multilayer films into their constituent resins using a series of solvent washes that are guided by thermodynamic calculations of polymer solubility. We show that the STRAP process is able to separate three representative polymers (polyethylene, ethylene vinyl alcohol, and polyethylene terephthalate) from a commercially available multilayer film with nearly 100% material efficiency, affording recyclable resins that are cost-competitive with the corresponding virgin materials.

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Detection Experiments of High-Barrier and High-Temperature Sterilization and Easy Tear Flexible Plastic Packaging Materials Applied in Food Packaging

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.117-119.1137 ◽

2011 ◽

Vol 117-119 ◽

pp. 1137-1141

Author(s):

Ling Yu Wang ◽

Jun Yan Huang ◽

Li Hua Cui

Keyword(s):

High Temperature ◽

High Resistance ◽

Food Packaging ◽

Raw Materials ◽

Packaging Material ◽

Processing Technology ◽

Material Structure ◽

Packaging Materials ◽

Plastic Packaging ◽

Detection Analysis

In order to study the characteristics of a new kind of high-barrier and high-temperature sterilization and easy tear flexible plastic packaging materials applied in food packaging, the PET/AL/CPP was chosen as flexible plastic packaging material structure, different PET, CPP, alcohol inks, adhesives and other raw materials were selected for making a series of processing technology experiment and detection analysis. Then comparing the data obtained with the requirements, it was concluded that new flexible plastic packaging materials were extremely high resistance oxygen and resistance wet, high-temperature sterilization and good one-way easy tear, and etc.

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Plastic packaging materials of laminated composites made of polymer cover sheets and a nonwoven interlayer

Journal of Sandwich Structures & Materials ◽

10.1177/1099636218795379 ◽

2018 ◽

Vol 22 (7) ◽

pp. 2287-2301

Author(s):

Mei-Chen Lin ◽

Jia-Horng Lin ◽

Jan-Yi Lin ◽

Ting An Lin ◽

Ching-Wen Lou

Keyword(s):

Mechanical Properties ◽

Laminated Composites ◽

Thermoplastic Polyurethane ◽

Soft Materials ◽

Packaging Materials ◽

Light Weight ◽

Plastic Packaging ◽

Crystal Stability ◽

High Toughness ◽

Sheet Extrusion

This study aims to improve the mechanical properties, stabilized structures, and light weight plastic packaging materials to realize diverse applications. A sheet extrusion machine is used to fabricate sandwich-structured composites, which are composed of two polymer cover sheets and a nonwoven interlayer. The samples are prepared in two batches with different cover sheets: thermoplastic polyurethane and polypropylene. Moreover, low-melting-point polyester (LMPET) fibers and Kevlar fibers are fabricated into a LMPET/Kevlar nonwoven interlayer. The laminated composites are evaluated in terms of morphologies, mechanical properties, combustion rates, and thermal behavior. Kevlar fibers are flame resistant and mechanically strong. LMPET fibers promote the interfacial bonding between layers. Thus, the laminated composites are good candidates as packaging materials, and they can be made with rigid or soft materials, depending on specified requirements. Rigid materials can provide higher strengths, and the distribution of fibers thus helps the PP-based laminated composites to obtain higher crystal stability. Moreover, using TPU with flexibility contributes to high extensibility, which grants the laminated composites with high toughness, light weight, and low restriction against the morphology. Such manufacturing is also efficient and economical, thereby satisfying the requirements of plastic packaging materials.

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Re-Processing of Multilayer Plastic Materials as a Part of the Recycling Process: The Features of Processed Multilayer Materials

Polymers ◽

10.3390/polym12112517 ◽

2020 ◽

Vol 12 (11) ◽

pp. 2517

Author(s):

Ville Lahtela ◽

Shekhar Silwal ◽

Timo Kärki

Keyword(s):

Mechanical Characteristics ◽

Wide Spectrum ◽

Packaging Materials ◽

Recycling Process ◽

Melt Flow Rate ◽

Plastic Packaging ◽

Food Packages ◽

Plastic Materials ◽

Materials Used ◽

Reuse Options

The weight of packaging materials will be increased with advanced innovations, such as multilayer plastic. The consequence of the advanced innovations is challenges in the following reuse activities. This study aimed to investigate the properties of multilayer plastic materials after recycling processes and will increase the awareness of plastic packaging material for reuse options. In this research, the materials were produced from food packages by crushing them and treating them with injection molding equipment. The implementation of materials in the processing was tested, and the structural and mechanical characteristics of the produced plastic materials was evaluated and discussed. Based on the completed tests, plastic materials used in food packages have the clearest differences in the material features, for instance, the melt flow rate and elongation rate in the tensile test that varied between 2.96–48.4 g/10min and 2–289%, respectively. The variation in the characterizations ranged widely between the material structures. The results indicate that solid plastic packaging materials have better mechanical features compared to foil materials. The structural analysis of materials showed that multilayer plastic includes a wide spectrum of different elements within materials, creating a challenge for future recycling.

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