3D printing PLA wastes were recovered from a well-known reference grade and from different sources. The recovered wastes were subjected to an energic washing step and then reprocessed into films by melt-extrusion, followed by compression molding to simulate the industrial processing conditions. The obtained materials were characterized and the optical, structural, thermal and crystallization behavior are reported. The mechanical recycling process leads to an increase of the crystallinity and a decrease of the intrinsic viscosity of the formulations, particularly in the sample based on blends of different 3D-PLA wastes. Moreover, the obtained films were disintegrated under composting conditions in less than one month and it was observed that recycled materials degrade somewhat faster than the starting 3D-PLA filament, as a consequence of the presence of shorter polymer chains. Finally, to increase the molecular weight of the recycled materials, the 3D-PLA wastes were submitted to a solid-state polymerization process at 110, 120, and 130 °C, observing that the recycled 3D-wastes materials based on a well-known reference grade experiences an improvement of the intrinsic viscosity, while that coming from different sources showed no significant changes. Thus, the results show that 3D printing PLA products provides an ideal environment for the implementation of distributed recycling program, in which wastes coming from well-known PLA grades can successfully be processed in films with good overall performance.

To move closer to achieving the United Nations’ Sustainable Development Goals (SDGs), a change from the traditional paradigm of the linear economy towards the circular economy is of paramount importance. One of the key promoters of this shift is servitization, which involves a shift from a purely transactional product-selling model to customer satisfaction through providing the service inherent to the product. Although servitization is a promising field for academics and practitioners, its adoption faces different challenges and drivers that need to be understood and addressed. A latent issue is the lack of common language around the topic. In the present study, a systematic literature review has been conducted to allow the identification and classification of the main challenges and drivers. Based on the findings, we propose a classification framework that identifies, classifies, and groups common challenges and drivers to different areas of knowledge on servitization through intensity heat maps. From a managerial point of view, our results highlight the importance of embracing servitization as a collective effort from the different departments within a company.

The circular economy model offers great opportunities to companies, as it not only allows them to capture additional value from their products and materials, but also reduce the fluctuations of price-related risks and material supply. These risks are present in all kind of businesses not based on the circular economy. The circular economy also enables economic growth without the need for more resources. This is because each unit has a higher value as a result of recycling and reuse of products and materials after use. Following this circular economics framework, the Polytechnic University of Madrid (Universidad Politécnica de Madrid, UPM) has adopted strategies aimed at improving the circularity of products. In particular, this article provides the result of obtaining recycled PLA filament from waste originating from university 3D FFF (fused filament fabrication) printers and waste generated by “Coronamakers” in the production of visors and parts for PPEs (Personal Protective Equipment) during the lockdown period of COVID-19 in Spain. This filament is used in the production of 3D printed parts that university students use in their classes, so the circular loop is closed. The obtained score of Material Circularity Indicator (MCI) of this material has been calculated, indicating its high level of circularity.

El objetivo de esta investigación es generar esquemas logísticos y comerciales rentables, para lo cual se construye una metodología que mide el costo de servir y se determina la rentabilidad a partir de los estados financieros, que va de lo general a lo específico, permitiendo cerrar las brechas identificadas en el análisis de costo de servir para mercados emergentes. La metodología consta de 3 fases y 12 pasos que alinean la estrategia, alcance, procesos y costeo de actividades con la segmentación de cuentas rentables, marginales y no rentables, para generar mayor rentabilidad. Como resultado se construyen herramientas que permiten priorizar a los clientes, así como definir la estrategia logística y comercial ideal para los objetos de estudio (cliente, producto, etc.).

This research employs an extensive multiple case studies analysis to identify the most important business models affecting supply chain configurations and related enabling technologies towards the creation of collaborative networks. The results obtained from the investigation of 24 companies of manufacturing and process industry, informed by literature, identify four 'design principles' of business models, i.e. Personalized production, Servitization, Decentralized and modular production, and Recycle, Re-use and Sustainability. Each model is further described and discussed at the interplay between digitalization and collaborative network practices at supply chain level, showing that adopting one or the combination of the four design principles allows to actuate some of the most important features of collaboration like Vertical integration or networking of smart production systems, Horizontal integration through global value chain networks, Through-engineering across the entire value chain, Acceleration of manufacturing and Digitalization of products and services.