Optimization of thermoplastic blend matrix HDPE/PLA with different types and levels of coupling agents

High-density polyethylene (HDPE) and poly(lactic) acid (PLA) blends with different ratios of both polymers, namely, 30:70, 50:50, and 70:30, were produced. Polyethylene-grafted maleic anhydride and a random copolymer of ethylene and glycidyl methacrylate were also considered as compatibilizers to modify HDPE/PLA optimal blends and were added in the amounts of 1, 3, and 5 wt.%. Different properties of the blends were evaluated by performing tensile tests and scanning electron microscopy to analyze blend and interfaces morphology. Moreover, thermomechanical analysis through differential scanning calorimetry, thermo-gravimetric analysis, and infrared spectroscopy were also performed. The blend containing equal amounts of HDPE and PLA seemed to present a good balance between amount of bio-derived charge and acceptable mechanical properties. This suggests that these blends have a good potential for the production of composites with lingo-cellulosic fillers

Dual morphology (fibres and particles) cellulosic filler for WPC materials

Wood-plastic composites (WPC) were fabricated by using a polyethylene (PE) matrix and filling it with wood flour in the amount of 30 wt.%, and compared with the same composites with further amount of 10 wt.% of cellulosic recycled fibres added. The materials were produced by turbomixing and subsequent moulding under pressure. Mechanical properties of both WPC and WPC with cellulosic recycled fibres were evaluated through mechanical and physical-chemical tests. Tensile tests clarified that a moderate reduction is strength is observed with the bare introduction of wood flour with respect to the neat PE matrix, whilst some recovery is offered by the addition of recycled cellulose fibres. Even more promisingly, the elastic modulus of PE matrix is substantially improved by the addition of wood flour (around 8% on average) and much more so with the further addition of recycled cellulose (around 20% on average). The fracture surfaces from the tensile test were analysed by scanning electron microscope (SEM) indicating a reduction in microporosity as an effect of added cellulose. The water absorption test and the hardness measure (Shore D) were also performed. SEM analysis underlined the weak interface between both wood particle and cellulosic recycled fibres and matrix. The water absorption test showed a higher mass variation for pure WPC than WPC with cellulosic recycled fibres. The hardness measurement showed that the presence of cellulosic recycled fibres improves both superficial hardness of the composite and temperature resistance. © 2016 Author(s)

Experience of Material Tinkering from Waste in the Year 3-Year 5 Primary School Age Range as an Introduction to Design and Sustainability

A possibility increasingly experimented in the field of design to improve end-of-life sustainability is integration of agro-waste into materials. Design can “upcycle” waste, offering perceptive and aesthetical acceptance to objects produced from it. On-field experimentations can foster awareness over the possibility to modify objects lifecycle, avoiding a “use-and-throw” perspective, and exploring the identity of materials in their prospected field of application. This will be aimed at creating a bond between user and objects, based both on function and on affection, also considering the modifications the material can undergo over time, making it adapted to different uses. This practice can have a significant educational value: in particular, this study moves from an experimentation carried out at July and September 2017 by design and materials engineering researchers, with several groups of 15 children, age 8-11, at Museo dei Bambini-Explora in Rome, investigating their “experience” and “creativity” on the topic. Conclusions are also drawn on possible modifications of the step-like procedure to introduce students of all ages to the knowledge of experimental method through the production of DIY bioplastics from waste. This “trial and error” procedure allows reflecting from a play-like point of view on aspects essential for the success of this operation, such as mode of coloration, effect of texture, possibility of obtaining curved or complex shapes, mechanical workability, optimal cooking and aromatization. The consequence of the exercise is customizing materials obtained from waste, with the idea of teaching how an expressive and functional success of the objects produced can make these “resilient” over time, therefore inherently sustainable. This would lead, through a combined and simple teaching of elements of experimental procedure and sustainability, to an awareness of their respective importance in design. The tool for this result is the development of DIY materials. The significance of this experience, which could be applied also in other age ranges, appeared to be to communicate the role of design to improve the perception of materials by transforming them into valuable objects. This proved to be better explained in the challenging case of waste, hence a substance bearing no longer any emotional or functional relation with us, with which this “bond” needs to be rebuilt through an experiential path.  Keywords: design education; material tinkering; sustainability for childre

Experience of Material Tinkering from Waste in the Year 3-Year 5 Primary School Age Range as an Introduction to Design and Sustainability

A possibility increasingly experimented in the field of design to improve end-of-life sustainability is integration of agro-waste into materials. Design can “upcycle” waste, offering perceptive and aesthetical acceptance to objects produced from it. On-field experimentations can foster awareness over the possibility to modify objects lifecycle, avoiding a “use-and-throw” perspective, and exploring the identity of materials in their prospected field of application. This will be aimed at creating a bond between user and objects, based both on function and on affection, also considering the modifications the material can undergo over time, making it adapted to different uses. This practice can have a significant educational value: in particular, this study moves from an experimentation carried out at July and September 2017 by design and materials engineering researchers, with several groups of 15 children, age 8-11, at Museo dei Bambini-Explora in Rome, investigating their “experience” and “creativity” on the topic. Conclusions are also drawn on possible modifications of the step-like procedure to introduce students of all ages to the knowledge of experimental method through the production of DIY bioplastics from waste. This “trial and error” procedure allows reflecting from a play-like point of view on aspects essential for the success of this operation, such as mode of coloration, effect of texture, possibility of obtaining curved or complex shapes, mechanical workability, optimal cooking and aromatization. The consequence of the exercise is customizing materials obtained from waste, with the idea of teaching how an expressive and functional success of the objects produced can make these “resilient” over time, therefore inherently sustainable. This would lead, through a combined and simple teaching of elements of experimental procedure and sustainability, to an awareness of their respective importance in design. The tool for this result is the development of DIY materials. The significance of this experience, which could be applied also in other age ranges, appeared to be to communicate the role of design to improve the perception of materials by transforming them into valuable objects. This proved to be better explained in the challenging case of waste, hence a substance bearing no longer any emotionalor functional relation with us, with which this “bond” needs to be rebuilt through an experiential path

Material tinkering for design education on waste upcycling

Materials are primary elements in the process of design and more and more are gaining attention in the design education.  The present work illustrates the practice of material tinkering, concentrating on its effects on design education, as regards the upcycling of waste into material demonstrators, deemed to assess their possibility to evolve into sustainable artefacts. After a general illustration of scope and objectives of material tinkering, the exposition describes the recent experiences of this practice into design schools, highlighting its pedagogical significance worldwide, and in the particular case of the Italian situation. Finally, the exposition concentrates in the specific case of work carried out in two prestigious Italian Universities (Università di Camerino and Politecnico di Milano) from 2015, trying to clarify its position and significance concerning previous literature, for what appears relevant to the education of designers and for their formation in the local context to be applicable worldwide. The research method evolves from trial-and-error, typical of experimentation on materials, to the conception of material demonstrators and suitability to be applied into products, having as boundaries the fact to use some kinds of waste in an upcycling philosophy

The Design of Plant Fibres as Biomimetic Composites

Las fibras vegetales, que se basan en estructuras ligno-celulósicas, están dispuestas como compuestos biomiméticos, en el sentido de que incluyen una relación compleja entre una matriz más blanda y un refuerzo más duro a través de una interfaz, con uso continuo de porosidades y arreglos celulares. Sin embargo, las fibras se pueden extraer de diferentes partes de la planta según la especie, en la práctica del tallo, la corteza, el fruto, la hoja o incluso la semilla. Existe una relación entre la región de las fibras y su estructura, que este trabajo pretende discutir, presentando una gran variedad de fibras, geometrías y colocaciones en la propia planta.Plant fibres, which are based on lignocellulosic structures, are arranged as biomimetic composites, in the sense that they include a complex relationship between a softer matrix and a harder reinforcement through an interface, with continuous use of porosities and cellular arrangements. However, the fibres can be extracted from different parts of the plant according to the species, in practice from the stem, the bark, the fruit, the leaf or even the seed. There is a relation between the fibre region and their structure, which this work aims to discuss, presenting a large variety of fibres, geometries and collocation in the plant itself.As fibras vegetais, que se baseiam em estruturas lignocelulósicas, apresentam-se como compósitos biomiméticos, no sentido de que apresentam uma relação complexa entre uma matriz mais macia e um reforço mais duro por meio de uma interface, com uso contínuo de porosidades e arranjos celulares. Porém, as fibras podem ser extraídas de diferentes partes da planta de acordo com a espécie, na prática do caule, da casca, do fruto, da folha ou mesmo da semente. Existe uma relação entre a região das fibras e sua estrutura, que este trabalho pretende discutir, apresentando uma grande variedade de fibras, geometrias e colocações na própria planta

Interaction with water in nature and self-cleaning potential of biological materials and species

Self-cleaning is an important characteristics of many biological species, considerably investigated in the biomimetic literature, with the aim to offer it into innovative materials. To try to summarize the different properties of bio-inspired materials having self-cleaning effect, different modes of classification have been proposed. In particular, either a paradigmatic species is cited, for example “lotus effect”, “rose petal effect”, etc., or a physical property is mentioned, such as super-hydrophobicity, super-oleophobicity, etc. This work considers some different modes in which nature implements self-cleaning as a form of effective interaction with water, depending on the respective needs of the various species. With this aim, a sample of ten species, selected among those which have been more investigated in biomimetic literature, have been considered. An attempt of classification is then given, trying to offer information for the development of new materials inspired from nature offering self-cleaning properties in different conditions of application.La autolimpieza es una característica importante de muchas especies biológicas, ampliamente investigada en la literatura biomimética, con el objetivo de ofrecerla en materiales innovadores. Para tratar de resumir las diferentes propiedades de los materiales bioinspirados que tienen un efecto autolimpiante, se han propuesto diferentes modos de clasificación. En particular, se cita una especie paradigmática, por ejemplo, "efecto de loto", "efecto pétalo de rosa", etc., o se menciona una propiedad física, como superhidrofobicidad, supeoleofobia, etc. Este trabajo considera algunas diferencias modos en los que la naturaleza implementa la autolimpieza como una forma de interacción efectiva con el agua, dependiendo de las necesidades respectivas de las diversas especies. Con este objetivo, se ha considerado una muestra de diez especies, seleccionadas entre las que han sido más investigadas en la literatura biomimética. Luego se realiza un intento de clasificación, tratando de ofrecer información para el desarrollo de nuevos materiales inspirados en la naturaleza que ofrecen propiedades de autolimpieza en diferentes condiciones de aplicación.A autolimpeza é uma característica importante de muitas espécies biológicas, consideravelmente investigada na literatura biomimética, com o objetivo de oferecê-la em materiais inovadores. Para tentar resumir as diferentes propriedades de materiais bioinspirados com efeito de auto-limpeza, diferentes modos de classificação foram propostos. Em particular, ou uma espécie paradigmática é citada, por exemplo, “efeito de lótus”, “efeito de pétala de rosa”, etc., ou uma propriedade física é mencionada, como super-hidrofobicidade, super-oleofobicidade, etc. Este trabalho considera algumas diferenças. modos em que a natureza implementa a autolimpeza como forma de interação efetiva com a água, dependendo das respectivas necessidades das várias espécies. Para tanto, foi considerada uma amostra de dez espécies, dentre as que foram mais investigadas na literatura biomimética. É feita uma tentativa de classificação, tentando oferecer informações para o desenvolvimento de novos materiais inspirados na natureza, oferecendo propriedades autolimpantes em diferentes condições de aplicação

Extraction of cellulose from different waste materials as a means to illustrate the relevance and the possibilities of the process of waste upcycling

The aim of this work is illustrating a possible example for explaining the upcycling of waste, hence producing value from it, for possible future use e.g., as viscose in the fashion industry. This has been performed by comparing the results obtained from different cellulose waste, especially yield of the product and its apparent quality. The first objective of the experiments is explaining the chemical procedure to recover cellulose waste for further use. After this, the cellulose extracted is characterized as concerns its morphological structure in terms of dimensions of the fibers obtained. Then, infrared analysis data are compared with those available from previously analyzed cellulose with known composition. Through this experience, the students are introduced to the importance of upcycling in general terms, starting with examples of though they are also presented with the very variable quality of the product obtained from cellulose waste, so to be able to make considerations about the possibility to proceed with the experiment and eventually developing it to an industrial level