FDM is 3D printing technology using mainly PLA and ABS as filament materials. PP has close characteristics to PLA and, due to that, is a potential material for for deposition. Paper aims to analyse the behaviour of PP during heating cycle specific to 3D printing process. Macroscopic and microscopic analysis of the deposited strings have been performed. They revealed less stiffness of the PP deposition comparing to PLA, which is due to the lower viscosity of PP. DSC Thermal analysis has been done at it revealed a 30% higher heat flux in PP comparing to PLA and that increases its fluidity. It was recorded a difference between the elongation viscosity of the PP filament and the PP deposited by FDM process. After 5s the deposited PP proves higher values for the elongation viscosity. Dynamic shear rheology measurements the was applied on samples deformed under 210 kN at 190oC. It has been found that the PP requires lower storage energy and that means that it has a lower viscosity for the entire range of applied frequencies. In the same time, the complex viscosities prove different behavior. To improve the control of the deposition shape, it is necessary to reduce the extrusion temperature with 4-5%. That leads to economy in power consumption.

The purpose of this article is to present an overview of the trend of using, on a wider scale, plastics in the automotive industry. It is presented the realization of PLA-TPU-Blends with a biogenic mass greater than 90%, by mixing thermoplastic Polyurethan (TPU) with Polylactid-Acid (PLA) at IKT University of Stuttgart. In order to estimate the possibilities of use of bio-materials made from PLA and TPU, the properties were compared with standard thermoplastics such as Polypropylen (PP), Polyethylen (PE), Polyamid (PA), as well as with better performing materials from the engineering thermoplastics range. PBT, ASA and their derivatives. Notable are the properties of PLA-TPU-Blends compared with standard thermoplastics PP, PE, PA. The results show PLA-TPU-Blends superiority in Yeld strength compared to the types of Polypropylene homopolymer (PP-H), block-copolymer (PP-B) and randompolymer (PP-R), the properties being adaptable by flexible modification of the ratio between the components, according to the requirements of the application. Using suitable additives to make components compatible, there were created blends which were partially cross-linked, but their properties remain of thermoplast. When reinforcing PLA-TPU-Blends with fibers (glass and natural), the components also react with the groups (-OH) on the fiber surface, thus making a good connection between fibers and blends, which prevents the so-called pull-out-effect. PLA-TPU-Blends reinforced with natural fibers can be used to make the interior body elements of vehicles. The paper also presents a comparison between bio-materials made at IKT University of Stuttgart with Polyethylen (PE) and other industry standard bio-materials.

Due to the continuous decrease in the level of oil resource, nowadays researchers from all fields are concerned with the creation of new bio plastics with special properties. The present work presents a series of such properties, which become achievable when reinforcing organic fibre materials obtained by reactive extrusion of thermoplastic Polyurethan (TPU) with Polylactid-Acid (PLA) in a twin-screw extruder and covalently linked into PLA-TPU-Blends, through the innovative one-step process technology, using the IMC Krauss Maffei injection moulding compounder, at the IKT University of Stuttgart. The elongation at break of PLA-TPU-Blends and the impact strength could be increased without significant reduction of strength and stiffness. A balanced relation between improved impact strength and reduced stiffness can be achieved by varying of the blend components. By using the partially biobased Polyurethane and natural fibres, a biobased content of more than 90% could be achieved. More and more advanced technologies allow the manufacture of components with reinforcements made of glass fibres, natural or carbon fibres obtained from polypropylene or Lignin. Due to their low specific weight compared to glass, carbon fibres are preferred for lightweight structures in the automotive or aeronautics industries. Green Carbon fibres, made in innovative ways from acrylonitrile resulting in the production of Bio-Diesel from algae, can successfully replace the conventional carbon fibres of Polypropylene, having identical properties. Fibre reinforcement aims to improve mechanical strength and impact resistance and increases the dimensional stability under heat of the composite. This feasibility study shows a method to realize fibre-reinforced materials using Green Carbon fibres with remarkable stability and rigidity similar or better than aluminum and steel for lightweight constructions.

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The developments of new and innovative materials are contributing significantly to the large scale such as automotive industry. Century by century uncountable inventions and developments were dedicated to synchronized technological advancement. Smart materials are highly efficient materials and their performance comes at high costs associated with the high level of R&D involved. Therefore, invention of these materials conceptualized to produce effective sensors and actuators according to the purpose. Some everyday items are already incorporating such smart materials, and the number of applications for them is growing steadily. Invention of functional and intelligent materials introduced new concept of intelligent infrastructure systems, autonomous systems, smart structures and robotics in the bygone years. Smart materials include the piezoelectric materials (PZT).