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Erneuerbare Werkstoffe (z.B. WPC) können metallische substituieren, indem eine Kombination aus technischen, wirtschaftlichen und ökologischen Vorteilen in Bauweise und Bauteilen in der Intralogistik Anwendung finden. Vorgestellt werden die wichtigsten Schritte zur Entwicklung eines Hängefördersystems mit einem Trag- und Gleitprofil aus WPC. Schwerpunkte sind die Verbindungsstellen, die Kurvensegmente und die Weiche. Es erfolgt eine Beurteilung der Gebrauchstauglichkeit des Gesamtsystems.

Poly butylene succinate (PBS) is a biodegradable plastic polymer that has physical and mechanical properties similar to common petroleum plastics like polypropylene (PP) and polyethylene (PE). PBS may be produced from petroleum or bio-based feedstocks, or by a hybrid combination of petroleum and bio-based resources. Producers are reducing content of petroleum components used for the production of PBS, and by doing so are seeking potential environmental performance improvements. In this study, ???hybrid??? PBS refers to the production of PBS polymer from bio-based succinic acid (SAC) sourced from sorghum and petroleum-based 1, 4-butanediol (BDO). Given its biodegradability, PBS is commercially used for compostable bags and agricultural mulching film applications. A recent study in Ontario identified composite materials made with PBS blended with natural fibres like switchgrass (SG) as promising for applications in automotive products. Such novel composite materials are touted as potential bio-based alternatives to conventional petroleum-based plastics. Of the few studies that have considered the environmental performance of PBS materials, none have assessed the potential environmental impacts of a hybrid PBS composite. Therefore, this study undertook a life cycle assessment (LCA) of SG reinforced hybrid PBS composite (hybrid composite). LCA is an environmental management technique that is used to assess environmental aspects (inputs and outputs) and potential environmental impacts of a product or service throughout its life cycle. The analysis considered a cradle-to-gate system boundary and evaluated eleven environmental performance indicators. The environmental performance of the hybrid composite was compared to a conventional glass fibre (GF) reinforced polypropylene (PP) composite (baseline composite), a material that is widely used in automotive components. Results showed that the production of the hybrid composite in comparison to the baseline composite decreased potential impact for most of the assessed indicators: cumulative energy demand by 40%, waste heat by 23%, global warming potential by 35%, smog by 2%, carcinogens by 54%, non-carcinogens by 172%, respiratory effects by 22% and ecotoxicity by 45%. Increases in the values of impact indicators were apparent for ozone depletion, acidification, and eutrophication by 43%, 16%, and 322%, respectively. Analysis revealed that dominant influences on results were not related directly to the bio-based make-up. Rather, the biggest influence on the environmental performance of composite production were the sources of heat used in petroleum-based materials, the energy mix in electricity for bio-based materials, the type of reinforcing fibre and the co-product treatment methodology used. The study helps fill a gap in knowledge regarding bio-based chemicals and hybrid biodegradable plastic composites, and points to opportunities for future research on feedstocks for industrial composite materials. The importance of this study is that it helps to identify the environmental strengths and weaknesses associated with the production of the hybrid composite specifically, and bio-based materials more generally. It points to alternative material substitution options for use in the automotive industry. In this study, life cycle assessment exemplifies multidisciplinary methodologies, which seek to traverse the boundaries between the social and natural sciences and disciplines to support more sustainable policy decisions for a bio-economy. The systematic nature and the widely applicable consequences of this LCA study have the potential to contribute to industrial and business management, and reach the public policy arena in an effort to drive environmental and social change.

Erneuerbare Werkstoffe (z.B. WPC) können metallische substituieren, indem eine Kombination aus technischen, wirtschaftlichen und ökologischen Vorteilen in Bauweise und Bauteilen in der Intralogistik Anwendung finden. Vorgestellt werden die wichtigsten Schritte zur Entwicklung eines Hängefördersystems mit einem Trag- und Gleitprofil aus WPC. Schwerpunkte sind die Verbindungsstellen, die Kurvensegmente und die Weiche. Es erfolgt eine Beurteilung der Gebrauchstauglichkeit des Gesamtsystems.

Abstract Electromagnetic shielding of nylon-66 composites applied to laser modules was studied experimentally and theoretically. The effects of conductive carbon fiber length and weight percentage upon the shielding effectiveness (SE) of nylon composites were investigated. The result showed that the SE of long carbon fiber filled nylon-66 composites was found to be higher SE than short carbon fiber filled nylon-66 composites under the same weight percentage of carbon fibers. In addition, higher electromagnetic shielding was obtained for the composite with higher contents of carbon fibers at the same length. The SE of conductive carbon fiber filled nylon-66 composites was measured to be 41 dB at low frequency of 30 MHz and 59 dB at high frequency of 1.5 GHz. The results of SE predicted by the proposed theoretical model and the results measured by experiments were in good agreement with each other for carbon fibers filled nylon-66 composites of different lengths. The effects of fiber orientation on SE of nylon and LCP composites were also investigated. The result showed that the SE of LCP composites was found to be higher than nylon composites under the same weight percentage of carbon fiber. This is due to that the fiber orientation in LCP composites attempts to keep the same direction.

Wood plastic composites (WPCs) were made using matrices of recycled high-density polyethylene (rHDPE) and polypropylene (rPP) with sawdust (Pinus radiata) as filler. Corresponding WPCs were also made using virgin plastics (HDPE and PP) for comparison with the recycled plastic based composites. WPCs were made through melt compounding and hot-press moulding with varying formulations based on the plastic type (HDPE and PP), plastic form (recycled and virgin), wood flour content and addition of coupling agent. The dimensional stability and mechanical properties of WPCs were investigated. Durability performances of these WPCs were studied separately, by exposing to accelerated freeze-thaw (FT) cycles and ultraviolet (UV) radiation. The property degradation and colour changes of the weathered composites were also examined. Dimensional stability and flexural properties of WPCs were further investigated by incorporation of nanoclays in the composite formulation. To understand the changes in WPCs stability and durability performance, microstructure and thermal properties of the composites were examined. Two mathematical models were developed in this work, one model to simulate the moisture movement through the composites in long-term water immersion and the other model to predict the temperature profile in the composites during hot-press moulding. Both rHDPE and rPP matrix based composites exhibited excellent dimensional stability and mechanical properties, which were comparable to those made from virgin plastics. Incorporation of maleated polypropylene (MAPP) coupling agent in composite formulation improved the stability and the mechanical properties. The incorporation of 3 wt. % MAPP coupling agent to WPCs showed an increase in tensile strength by 60% and 35 %, respectively, for the rHDPE based and rPP based composites with 50 wt. % wood flour. Scanning electron microscopy (SEM) images of the fractured surfaces of WPCs confirmed that the MAPP coupling improved the interfacial bonding between the plastic and the wood filler for both series of composites. Long-term water immersion tests showed that the water transport mechanism within the WPCs follows the kinetics of Fickian diffusion. Dimensional stability and flexural properties of the WPC were degraded after 12 accelerated FT cycles as well as 2000 h of UV weathering for both recycled and virgin HDPE and PP based composites. However, the MAPP coupled composites had improved stability and flexural property degradation. The surface of the weathered composites experienced a colour change, which increased with the exposure time. The MAPP coupled composites exhibited less colour change as compared to non-coupled composites. Regarding the effect of the plastic type, the PP based composites experienced higher colour change than those based on HDPE. With weathering exposure, flexural strength and stiffness of the WPCs were decreased, but elongation at break was increased regardless of plastic type and wood flour content. MAPP coupled rPP and rHDPE based UV weathered WPCs lowered the degradation of stiffness by 50% and 75%, respectively compared to non-coupled WPCs. SEM images of the fractured surfaces of FT and UV weathered WPCs confirmed a decrease in the interfacial bonding between the wood flour and matrix. Thermal properties of weathered composites changed with weathering, but the extent of the changes depended on WPCs formulation and matrix type. From the experimental studies on nanoclay-filled rHDPE composites, it is found that stability, flexural properties of WPCs could be improved with an appropriate combination of coupling agent, and nanoclay contents processed by melt blending. Incorporation of 1-5 wt. % nanoclay in the maleated polyethylene (MAPE) coupled wood plastic composite improved the dimensional stability and flexural properties. The thermal properties changed with the addition of nanoclay and MAPE in WPCs. In this work, a hot press-moulding model was proposed based on the one-dimensional transient heat conduction to predict the temperature profile of the WPCs during hot pressing cycle. The results from this work clearly show that rHDPE and rPP can be successfully used to produce stable and strong WPCs, which properties and performances are similar to or comparable to composites made of wood and virgin plastics. Therefore, WPCs based on recycled PP and HDPE matrix could have potential to use as construction materials.

Das Schweißen von WPC stellt zunächst aufgrund der thermoplastischen Matrix eine effektive Fügetechnologie dar. Der Beitrag behandelt das Heizelementschweißen von WPC und liefert Aussagen zur Wirkung der Prozessparameter auf die mechanischen und geometrischen Nahteigenschaften, dem Rezeptureinfluss und der thermischen Instabilität der Holzfaser. An den WPC-Rezepturen auf Basis von Polypropylen mit 40 Gew.-% und 50 Gew.-% Holzfasern sowie des Einsatzes von PET-Fasern im Compound, werden die Zusammenhänge untersucht und die Versagensmechanismen aufgezeigt.

Das Schweißen von WPC stellt zunächst aufgrund der thermoplastischen Matrix eine effektive Fügetechnologie dar. Der Beitrag behandelt das Heizelementschweißen von WPC und liefert Aussagen zur Wirkung der Prozessparameter auf die mechanischen und geometrischen Nahteigenschaften, dem Rezeptureinfluss und der thermischen Instabilität der Holzfaser. An den WPC-Rezepturen auf Basis von Polypropylen mit 40 Gew.-% und 50 Gew.-% Holzfasern sowie des Einsatzes von PET-Fasern im Compound, werden die Zusammenhänge untersucht und die Versagensmechanismen aufgezeigt.

Es werden die tribologische Eigenschaften von extrudierten WPC, gefüllt mit 70 mass.% ver-schiedener Holzarten, welche in einer PP-Matrix verarbeitet wurden charakterisiert. Weiterhin werden Untersuchungen zum Einfluss verschiedener Lager- und Umgebungsmedien auf die mechanischen Eigenschaften von WPC mit PP- und PE-Matrix bei einem Füllgrad von 30 bis 50 mass% vorgestellt. Auf Basis beider Untersuchungen wird eine Einschätzung der Dauergebrauchsfähigkeit von WPC für den Einsatz als Maschinenbaukomponente vorgenommen. / The tribological properties of extruded WPC are destined. The WPC was filled with 70 mass.% of various types of wood, which were processed in aPP matrix. Furthermore the influences of the environmental andvarious storage conditions with focus on the mechanical properties of WPC are examined. These specimens were made with a filling ratio of 30-50 mass % wood in a PP- and PE -Matrix. Based on this both studies, the serviceability and long term usability of WPC for the use as a functional machine element is investigated.

La présente étude fait suite à d’autres qui proposent une solution de récupération des déchets plastiques et de bois pour en faire un matériau de construction en composite bois-polymère. La particularité de ce travail de recherche est que la matrice thermoplastique utilisée est un ensemble de différents polymères pris dans des proportions bien définies. Les pourcentages considérés pour la matrice obtenue représentent les parts de déchets de polymères que l’on retrouve dans la ville de Cotonou (Bénin). Cette étude a consisté à fabriqué des échantillons de composite bois polymère CBP par extrusion, à les étudier à travers des tests physico-mécaniques et à les mettre en relation avec les échantillons fabriqués avec une méthode artisanale déjà existante. D’une part, nous avons étudié séparément la sciure de bois et la matrice thermoplastique en déterminant les constituants chimiques de la sciure de bois, et en effectuant une analyse physico-mécanique (analyse thermogravimétrique, test en flexion compression et traction, analyse du faciès de rupture au MEB) sur le renfort et la matrice. D’autre part nous avons évalué l’influence de l’ajout de 20%, 25%, 28% et 30% de sciure de bois sur les propriétés mécaniques (compression, flexion et traction). Les résultats obtenus révèlent que la sciure de bois se comporte comme un renfort lorsque l’échantillon est sollicité en compression et en flexion. La sciure de bois joue le rôle de charge lorsque les échantillons de CBP sont sollicités en traction. Par ailleurs, la sciure de bois améliore la rigidité des CBP en traction. Les résultats mécaniques obtenus par extrusion sont nettement meilleurs que ceux issus des méthodes de fabrication artisanale. Les analyses thermogravimétriques effectuées sur les échantillons de CBP issus de la méthode artisanale révèlent que lors de leur fabrication, ces échantillons sont soumis à des températures (supérieure à 300°C) qui entament la dégradation des polymères et de la sciure de bois dans les CBP / This study follow others that propose a solution for the recovery of plastic waste and wood to make it a construction material made of wood-polymer composite. The particularity of this research is that the thermoplastic matrix used is a set of different polymers taken in well-defined proportions. The percentages considered for the matrix obtained represent the proportion of polymer waste that can be found in the city of Cotonou (Benin Republic). This study consisted in making WPC polymer wood composite samples by extrusion, studying them through physico-mechanical tests and relating them to samples made with an already existing artisanal method. On the one hand, we studied separately the sawdust and the thermoplastic matrix by determining the chemical constituents of the sawdust, and by performing a physico-mechanical analysis (thermogravimetric analysis, compression and tensile bending test, facies analysis). SEM fracture) on the reinforcement and the matrix. On the other hand we evaluated the influence of the addition of 20%, 25%, 28% and 30% of sawdust on the mechanical properties (compression, bending and traction). The results show that sawdust behaves like a reinforcement when the sample is stressed in compression and bending. Sawdust acts as a load when WPC samples are stressed in tension. Sawdust also improves the rigidity of WPC in tension. The mechanical results obtained by extrusion are much better than those resulting from the artisanal methods. Thermogravimetric analyzes performed on WPC samples from the artisanal method reveal that during their manufacture, these samples are subjected to temperatures (above 300 ° C) that begin the degradation of polymers and sawdust in WPC