No abstract

Biogenic wood‐plastic composites from bio‐based polymers and wood fibers (bio‐WPC) provide an improved sustainability and carbon footprint compared to conventional composites. Recently, such bio‐WPCs from bio‐based polyamides have gained major interest due to their high mechanical and thermomechanical properties. In this study, the resulting mechanical and thermo‐mechanical properties of two bio‐WPCs from polyamide 11 (PA11) and polyamide 10.10 (PA10.10) with a content of 30 wt% of beech wood particles (BP), processed by twin‐screw compounding and subsequent injection molding, are analyzed by tensile testing and dynamic mechanical analysis. For this, two comparable grades of PA11 and PA10.10 are used. It is found that the elastic modulus, tensile strength, and the temperature‐dependent storage modulus of the PA10.10/BP30 are significantly higher as compared to the PA11/BP30 material. These findings are addressed to the different number of amino groups per repeating unit in these polymers, leading to a better adhesion of the matrix and the wood fiber and consequently better mechanical and thermomechanical properties of the PA10.10/BP30. In consequence, bio‐WPCs from PA10.10 should be considered as an interesting alternative with a tendency to higher mechanical and thermomechanical properties in comparison to bio‐WPCs from PA11.

Direct compounding injection molding of ternary blends of polylactide (PLA), polybutylene succinate (PBS) and a hydrogenated styrene farnesene block copolymer (HSFC) was investigated for different blend compositions. Morphological analysis by atomic force microscopy and scanning electron microscopy showed a heterogeneous morphology of the ternary blends, with coexisting droplets of HSFC and PLA respectively PBS. Particle sizes analysis of the minor phases in the ternary blends showed mean values in the range of ∼1 μm, which is discussed in correlation to the rheological properties of the blend components as obtained by high pressure capillary rheometry. In result, with increasing HSFC content, the ternary blends showed a significant increase in notched Charpy impact strength (acN). In concrete, for the ternary blends with 15 wt% of HSFC a maximum acN of 15.8 kJ/m2 was found. At the same time, incorporation of the HSFC resulted only in a moderate reduction in elastic modulus and tensile strength.

Climate change, critical material shortages and environmental degradation pose an existential threat to the entire world. Immediate action is needed to transform the global economy towards a more circular economy with less intensive use of fossil energy and limited resources and more use of recyclable materials. Recyclable materials and manufacturing techniques will play a critical role in this transformation. Substantial advancements will be needed to achieve a more intelligent materials design to enhance both functionality and enhanced sustainability. The development of hybrid materials combining functionality at macro and nano scales based on organic and inorganic compounds, that are entirely recyclable could be used for tremendous applications. In this mini-review, we provide the reader with recent innovations on hybrid materials for application in water, energy and raw materials sectors. The topic is very modern and after its deep study we propose a creation an international research centre, that would combine the development of hybrid materials with green manufacturing. We have highlighted a framework that would comprise critical themes of the initial research needed. Such a centre would promote sustainable production of materials through intelligent hybridisation and eco-efficient, digital manufacturing and enable a circular economy in the long term. Such activities are strongly supported by current environmental and economical initiatives, like the Green Deal, REPower EU and digital EU initiatives.