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Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Dalian University of Technology / Dalian Ligong Daxue Xuebao is the property of Journal of Dalian University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• Surface modification of MFPW flakes improves the delamination process. • Surface modification allows the penetration of the dissolving agent inside MFPW. • The delamination time strongly depends on the distance between the microholes. • Abrasion of the MFPW surface increases the specific surface of the cross section area. Multilayer flexible packaging waste (MFPW) represents a critical issue in the field of waste management. The heterogeneous composition of this type of plastic makes its recyclability challenging. In this context, the delamination process appears to be a promising way to recycle the polymers layers separately. However, this process is still limited for a few MFPW. This work propose an innovative way to improve the delamination process using three surface modification techniques (mechanical and laser microperforation (µP), and abrasion) on the MFPW surface in order to accelerate the diffusion of the dissolving agent. The delamination was tested in a 10 % sodium hydroxide solution at 25ºC. Under this study, the mechanical µP and the abrasion gave the best results of delamination compared to the laser µP (total delamination in 25 min vs 45 min, respectively). It was concluded that the distance between the microholes was an important factor in both µP techniques. [Display omitted] [ABSTRACT FROM AUTHOR]

While algorithmic management provides new options for organizing service work, it is underexplored in tourism and hospitality research. From food-delivery platforms in China, this qualitative study sources interviews and online reviews to explore the impact of algorithmic management on workers' service behavior and how they cope in response. Our study uncovers an algorithm-human hybrid approach for managing workers, where algorithms and humans function distinctly but complement each other. Algorithmic management influences deliverers' work either positively, by improving service efficiency, reliability and customer-orientated behavior; or negatively by causing impersonal service behavior, frequent service recovery and extra-role workload. Deliverers employ both problem-focused (i.e., compliance, flexible response and resistance) and emotion-focused (i.e., relief) coping strategies in algorithmic management. In addition to individual resistance, we firstly revealed that deliverers collude with other parties to resist the algorithms. We proposed a conceptual framework that contributes to understanding the dynamic, mutual relationship between algorithms and workers. [ABSTRACT FROM AUTHOR]

• Economics & carbon footprint of a piloted US flexible plastic packaging recycling. • Roof coverboard, pallets, pellets, and film are downstream market pathways. • Cleaning and pelletizing steps contributed the most to recycled product footprints. • Recycled products are environmentally & economically better than competitors. As demand for plastic increases, there is an urgent need to ramp up its collection and recycling rate. This study reports results of a pilot study in the United States to recycle flexible plastic packaging (FPP) from single stream curbside collection focusing on both the economic feasibility and carbon footprint. To explore the marketability of recycled FPP, four downstream market pathways were studied, including roof coverboard, plastic pellets, pallets, and film. Results indicated that (1) the cleaning and pelletizing process at reclaimers contributed the most to the total greenhouse gas (GHG) emissions of recycled FPP products, and (2) the GHG emissions of recycled FPP products in all four pathways are lower than the comparator products. Therefore, using a higher percentage of recycled FPP substituted in a product can result in greater GHG emission reductions. All the recycled FPP products also showed favorable economics compared to their direct competitors. [ABSTRACT FROM AUTHOR]

Multilayer flexible packaging waste is a critical issue in the field of waste management as it is considered a non-recyclable material. One of the solutions to increase its recyclability is the delamination, which allows the recycling of the different polymer layers separately. This study investigated the optimization of the delamination by microperforating this plastic. The diffusion model was described by Fick's first law. The delamination process was tested at three different temperatures (50, 65 and 80 °C) with caustic soda. In addition, the influence of other parameters such as the thickness of aluminium layer, the presence of inks and the use of surfactants was tested. As a result, the microperforation technique improved the delamination rate by decreasing the residence time by 83% at the optimum conditions studied, being the thickness of the metal and the temperature essential factors affecting the process. However, the presence of inks and surfactant had no effect. [Display omitted] [ABSTRACT FROM AUTHOR]

A chemorheological analysis of a no-flow underfill was conducted using curing kinetics through isothermal and dynamic differential scanning calorimetry, viscosity measurement, and solder (Sn/27In/54Bi, melting temperature of 86 °C) wetting observations. The analysis used an epoxy system with an anhydride curing agent and carboxyl fluxing capability to remove oxide on the surface of a metal filler. A curing kinetic of the no-flow underfill with a processing temperature of 130 °C was successfully completed using phenomenological models such as autocatalytic and nth-order models. Temperaturedependent kinetic parameters were identified within a temperature range of 125 °C to 135 °C. The phenomenon of solder wetting was visually observed using an optical microscope, and the conversion and viscosity at the moment of solder wetting were quantitatively investigated. It is expected that the curing kinetics and rheological property of a no-flow underfill can be adopted in arbitrary processing applications. [ABSTRACT FROM AUTHOR]

The paper attempts to make an instrumental case in the area of lean and Just-In-Time operations in the flexible packaging industry. Lean operations, process mapping and streamlining, competing with time in delivering customer service, are discussed in the paper in order to highlight alternatives to manage costs in producing flexible packaging to deliver upon customer value. [ABSTRACT FROM AUTHOR]

Global maritime supply chain (MSC) faces increasing risks of uncertainty in the post COVID-19 era, ports disruptions and congestion are becoming common. To ensure high reliability of container shipping network, this paper study on the issue of locating hub ports and allocating non-hub ports (spokes) to hubs, meanwhile backup hub ports. An extended container shipping hub-and-spoke network design problem (HSN) is investigated, considering the failure and congestion of hubs, a 0–1 nonlinear programming model is developed for minimizing the transportation cost. Furthermore, we simulate container shipping network using Asia-Europe trade data, and propose the approach of particle swarm optimization (PSO) to solve the model. The experimental results show that path replacement cost and congestion cost affect the network design to a great extent, and backup hub ports could improve the reliability of global container shipping networks for capacity scheduling and allocation. This study can provide certain useful managerial insights for the liner company's daily operation, and design flexible container shipping HSN to ensure maximum efficiency after the COVID-19 irruption. [ABSTRACT FROM AUTHOR]

Flexible plastic packaging is still one of the most difficult streams to recycle due to the presence of multilayers. With multilayers being very functional during their use phase, the delamination of multilayer structures is promising because it enables the recovery of the constituent polymer layers without any degradation and/or dissolution, thus creating economic and environmental benefits. However, there is hardly any data available on the optimization of the delamination process for multilayer flexible plastic films (MFPFs), as well as the potential scale-up in terms of economic and environmental factors. Therefore, this study investigates the effect of experimental parameters such as temperature, solid/liquid (S/L) ratio, particle size, and stirring rate on the delamination rate of various MFPFs. Among these parameters, the combination of temperature and S/L ratio has the most pronounced effect on increasing the delamination rate. On the other hand, particle size does not have a significant influence on the delamination rate. Under optimal delamination conditions, more than 90% delamination is achieved in 60 min, particularly for PET-based MFPF. Simulations of the delamination process in Aspen Plus® reveal that the composition of MFPF has a significant effect on the energy consumption during the delamination process. The slower delamination kinetics of MFPFs can be compensated for through process optimization, but this typically results in higher energy requirements. The life cycle assessment (LCA) confirms that high energy consumption results in high CO 2 emissions; thus, design for MFPFs, together with process optimization, are key aspects of obtaining a competitive delamination process with economic and environmental benefits. Graphical Abstract [Display omitted]. [ABSTRACT FROM AUTHOR]

• A design-for-recycling approach has been applied to realize high performance films for packaging applications. • Mono-material polyolefin flexible films with remarkable barrier properties to gases and UV radiation have been developed by applying coatings based on graphene derivatives. • The applied coatings show very regular morphology, and do not alter the flexibility and the overall mechanical properties of the substrates. • The new barrier films are easy recyclable, as demonstrated by their reprocessing by extrusion and compression moulding. • The proposed materials represent a promising solution to realize polymer based high performance mono-material products with a sustainable end-of-life option. Due to the large production of plastic packaging, packaging mismanagement represents a significant problem for the environment and the related economic/social contexts. A new route towards sustainable recycling has been identified in the design of the plastic products together with their end-of-life recycling options. Following this approach, in this work, new recyclable-by-design mono-material flexible films with high barrier properties to gases and UV radiation have been developed by applying graphene oxide (GO) and graphene oxide/montmorillonite (GO/MMT) hybrid coatings on polyolefin substrates. The coatings induce a remarkable reduction of the UV transmittance (40–60%) and of the oxygen (94–99%) and water vapour (68–73%) permeability of the films, with very good stability after prolonged water immersion. Reprocessing tests demonstrate the easy recyclability of the coated films, whose commercial analogues are currently considered as non-recyclable. By extrusion and compression moulding, recycled films are obtained in which the nanostructured phases result well embedded in the polymer matrices. The mechanical properties of the samples obtained by reprocessing coated polyethylene and polypropylene films are comparable to those of the reprocessed pristine films. Moreover, no significant release of GO by water immersion for 24 h at room temperature is detected from the recycled samples. Overall, the results indicate that the application of thin GO/MMT coatings to realize mono-material barrier films for packaging applications is an effective strategy to realize high performance products able to be easily recycled. These mono-material flexible films represent a new sustainable end-of-life option with respect to current commercial multi-layer products. [Display omitted] [ABSTRACT FROM AUTHOR]