Value preservation is key for the transition from a linear economy to a sufficiency-based circular economy. However, to keep the value of products and materials at the highest level possible over time, different actors such as businesses, designers, consumers, and policymakers must know when value is reduced during a product's lifetime, and how to capture and preserve this value. This study results in a comprehensive mapping of factors with a negative impact on the perceived value of products from a consumer's perspective and suggests new routes to value preservation, as a way of turning the negative factors into positive changes. Next, the paper presents a conceptual model for value preservation. The model identifies new key actors: value transformers (product developers), value co-operators (consumers), value gatekeepers (businesses), and value accountants (policymakers) and suggests important changes to their linear practices, which are needed for the sufficiency-based circular economy paradigm to flourish.@en

This paper addresses the fracture behaviour of bonded composite plates featuring a kissing bond along the crack growth path. Double cantilever beam (DCB) experiments are carried out under a displacement controlled loading condition to acquire the load response. The experimental data are collected and analysed analytically for specimens with and without kissing bond. The following aspects are observed and discussed: effect of the adhesive carrier film, non-smooth crack growth and rising R curve. An analytical model taking into account the aforementioned effects is proposed. The kissing bond leads to unstable crack growth resulting in a loss of the load carrying capacity. The presence of the knit carrier in the adhesive film results in the crack growth process characteristic for the stick-slip phenomena and a significant increase of the resistance to fracture of the bondline by triggering a bridging phenomenon. The model shows a very good agreement with the experimental data. A sound understanding of the fracture process is gained enabling analysis and prediction of the effects of kissing bonds and supporting carrier.

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