Creep deflection of Wood Polymer Composite profiles at demanding conditions

Durability and low maintenance make Wood Polymer Composite (WPC) profiles popular in decking applications. EN 15534-4 specifies minimum performance levels to guarantee WPC quality. However, despite such quality specifications, occasionally high temperature creep issues are reported. This paper evaluates the creep performance of three commercial WPC decking profile grades. All three WPC grades meet the requirements specified in EN 15534-4. Nevertheless, at slightly more demanding load conditions, some WPC samples fail around the creep deflection limits specified in the standard, and which are supposed safe. Reference outdoor testing in the moderate climate of the Netherlands shows creep deflection rates which are expected to lead to fatal failure of these WPC samples in a couple of years. It is concluded that predictive testing requires insight in progressive creep strain development relative to fatal failure strain level.</p

The paradox between the environmental appeal of bio-based plastic packaging for consumers and their disposal behaviour

To realize the potential environmental benefits that recycling and/or composting bio-based plastic packages can deliver, it is important that consumers view bio-based packaging as environmentally-friendly, but also correctly dispose of the packaging. The current experimental lab-in-the-field study was conducted among German consumers (n = 281) and explores whether consumers' perceived environmental benefits of recyclable and compostable bio-based plastic packages match with how consumers dispose of these packages. The results show that consumers only perceive compostable bio-based packages to have more environmental benefits than fossil-based packages. However, consumers dispose of compostable bio-based packages in an incorrect manner (not in line with what is communicated on the packaging label) relatively often. Consumers with a stronger familiarity with bio-based products more often correctly dispose of compostable bio-based packages, but not recyclable bio-based packages, relative to fossil-based packages. Thus, although mainly compostable bio-based plastic packages have strong environmental appeal to consumers, paradoxically this does not translate in the proper disposal actions to fully capitalize on the environmental benefits that bio-based packages can actually deliver. Increasing consumers' bio-based product familiarity might be an avenue to increase the levels of sustainable disposal.</p

Flexible laminates within the circular economy

This report focusses on flexible laminated packages that are composed out of multiple polymer types and their impact on the recycling chains. Approximately 3-4% of the packaging products used in Europe is a laminated flexible packaging film. By nature, these films are either more difficult to recycle than mono-material packaging products, or even impossible to recycle. In the Netherlands roughly 65% of the laminated flexibles are discarded with the mixed municipal solid waste and 35% are collected in separate collection schemes for lightweight packaging wastes. After sorting the laminates are distributed over the various sorted products; roughly 60% ends up in the sorted product MIX, 25% in the sorted product FILM, 10% in the various sorting residues and 5% in valuable sorting products like PP and PE where they may hinder recycling of these valuable sorting products. Current and future options for the waste management of multi-material laminated flexible packaging films include mechanical-, chemical- and organic recycling. Next to technical feasibility and technical hurdles there are various practical and economical limitations and acceptance issues that presently limit recycling of flexible laminates. Most stakeholders involved in plastic packaging are committed to develop a more sustainable, circular plastics industry. Despite the willingness of industry to move to sustainable and recyclable packaging products there are numerous challenges with respect to flexible laminates for packaging applications. Strategies to improve the end-of-life options for flexible laminates can be categorised in four main categories; avoid the use of laminates, redesign the laminates, redesign the collection & recycling scheme or improve the sort-ability and recognisability. As a first step (agreement on) a precise definition of recyclability is needed to allow evaluation of the recyclability of laminated flexible packages. This implies that a test method is needed to verify if newly developed laminated flexibles are recyclable

Chitin Nanocrystal Hydrophobicity Adjustment by Fatty Acid Esterification for Improved Polylactic Acid Nanocomposites

Bioplastics may solve environmental issues related to the current linear plastic economy, but they need improvement to be viable alternatives. To achieve this, we aimed to add chitin nanocrystals (ChNC) to polylactic acid (PLA), which is known to alter material properties while maintaining a fully bio-based character. However, ChNC are not particularly compatible with PLA, and surface modification with fatty acids was used to improve this. We used fatty acids that are different in carbon chain length (C4–C18) and degree of saturation (C18:2). We successfully used Steglich esterification and confirmed covalent attachment of fatty acids to the ChNC with FTIR and solid-state 13C NMR. The morphology of the ChNC remained intact after surface modification, as observed by TEM. ChNC modified with C4 and C8 showed higher degrees of substitution compared to fatty acidswith a longer aliphatic tail, while particles modified with the longest fatty acid showed the highest hydrophobicity. The addition of ChNC to the PLA matrix resulted in brown color formation that was reduced when using modified particles, leading to higher transparency, most probably as a result of better dispersibility of modified ChNC, as observed by SEM. In general, addition of ChNCprovided high UV protection to the base polymer material, which is an additional feature that can be created through the addition of ChNC, which is not at the expense of the barrier properties, or the mechanical strength

Flexible laminates within the circular economy

This report focusses on flexible laminated packages that are composed out of multiple polymer types and their impact on the recycling chains. Approximately 3-4% of the packaging products used in Europe is a laminated flexible packaging film. By nature, these films are either more difficult to recycle than mono-material packaging products, or even impossible to recycle. In the Netherlands roughly 65% of the laminated flexibles are discarded with the mixed municipal solid waste and 35% are collected in separate collection schemes for lightweight packaging wastes. After sorting the laminates are distributed over the various sorted products; roughly 60% ends up in the sorted product MIX, 25% in the sorted product FILM, 10% in the various sorting residues and 5% in valuable sorting products like PP and PE where they may hinder recycling of these valuable sorting products. Current and future options for the waste management of multi-material laminated flexible packaging films include mechanical-, chemical- and organic recycling. Next to technical feasibility and technical hurdles there are various practical and economical limitations and acceptance issues that presently limit recycling of flexible laminates. Most stakeholders involved in plastic packaging are committed to develop a more sustainable, circular plastics industry. Despite the willingness of industry to move to sustainable and recyclable packaging products there are numerous challenges with respect to flexible laminates for packaging applications. Strategies to improve the end-of-life options for flexible laminates can be categorised in four main categories; avoid the use of laminates, redesign the laminates, redesign the collection & recycling scheme or improve the sort-ability and recognisability. As a first step (agreement on) a precise definition of recyclability is needed to allow evaluation of the recyclability of laminated flexible packages. This implies that a test method is needed to verify if newly developed laminated flexibles are recyclable

A Review on the Potential and Limitations of Recyclable Thermosets for Structural Applications

The outstanding performance of conventional thermosets arising from their covalently cross-linked networks directly results in a limited recyclability. The available commercial or close-to-commercial techniques facing this challenge can be divided into mechanical, thermal, and chemical processing. However, these methods typically require a high energy input and do not take the recycling of the thermoset matrix itself into account. Rather, they focus on retrieving the more valuable fibers, fillers, or substrates. To increase the circularity of thermoset products, many academic studies report potential solutions which require a reduced energy input by using degradable linkages or dynamic covalent bonds. However, the majority of these studies have limited potential for industrial implementation. This review aims to bridge the gap between the industrial and academic developments by focusing on those which are most relevant from a technological, sustainable and economic point of view. An overview is given of currently used approaches for the recycling of thermoset materials, the development of novel inherently recyclable thermosets and examples of possible applications that could reach the market in the near future.</p