The working hypothesis for this research project is that it is possible to develop a new functional polymer printing process for the direct application of conductive polymer onto textiles. We will use the basic extrusion technology that is currently applied in 3D printing. Thus the aim is also expanding the knowledge and knowhow base of 3D printing and make this technology applicable for deposition of functional polymers on textiles in such a way that process parameters are clearly understood, and pre-defined final product specifications can be met. Thus the challenge is to apply conductive tracks with a simple one step process that fits the current textile production processes. This means that investigating polymer deposition onto textiles of bio based polymers like PLA, doped with carbon could be a versatile route to achieving economic and sustainable conducting textiles. If the mechanism underlying the bonding of doped PLA with textiles can be controlled for processing then a new route to achieving conductive grids would be opened.Paper written by the Saxion chair Smart Functional Materials and The Unversity of Twente for and accepted by the Autex Conference 2013 (22-24 May 2013, Dresden, Germany).
MULTIFILE
Inkjet printing is a rapidly growing technology for depositing functional materials in the production of organic electronics. Challenges lie among others in the printing of high resolution patterns with high aspect ratio of functional materials to obtain the needed functionality like e.g. conductivity. μPlasma printing is a technology which combines atmospheric plasma treatment with the versatility of digital on demand printing technology to selectively change the wetting behaviour of materials. In earlier research it was shown that with μPlasma printing it is possible to selectively improve the wetting behaviour of functional inks on polymer substrates using atmospheric air plasma. In this investigation we show it is possible to selectively change the substrate wetting behaviour using combinations of different plasmas and patterned printing. For air and nitrogen plasmas, increased wetting of printed materials could be achieved on both polycarbonate and glass substrates. A minimal track width of 320 μm for a 200 μm wide plasma needle was achieved. A combination of N2 with HMDSO plasma increases the contact angle for water up from <100 to 1050 and from 320 to 460 for DEGDMA making the substrate more hydrophobic. Furthermore using N2-plasma in combination with a N2/HMDSO plasma, hydrophobic tracks could be printed with similar minimal track width. Combining both N2 -plasma and N2/HMDSO plasma treatments show promising results to further decrease the track width to even smaller values.
In this article we investigate the change in wetting behavior of inkjet printed materials on either hydrophilic or hydrophobic plasma treated patterns, to determine the minimum obtainable track width using selective patterned μPlasma printing. For Hexamethyl-Disiloxane (HMDSO)/N2 plasma, a decrease in surface energy of approx. 44 mN/m was measured. This resulted in a change in contact angle for water from <10 up to 105 degrees, and from 32 up to 46 degrees for Diethyleneglycol-Dimethaclylate (DEGDMA). For both the nitrogen, air and HMDSO/N2 plasma single pixel wide track widths of approx. 320 μm were measured at a plasma print height of 50 μm. Combining hydrophilic pretreatment of the glass substrate, by UV/Ozone or air μPlasma printing, with hydrophobic HMDSO/N2 plasma, the smallest hydrophilic area found was in the order of 300 μm as well.
Recycling of plastics plays an important role to reach a climate neutral industry. To come to a sustainable circular use of materials, it is important that recycled plastics can be used for comparable (or ugraded) applications as their original use. QuinLyte innovated a material that can reach this goal. SmartAgain® is a material that is obtained by recycling of high-barrier multilayer films and which maintains its properties after mechanical recycling. It opens the door for many applications, of which the production of a scoliosis brace is a typical example from the medical field. Scoliosis is a sideways curvature of the spine and wearing an orthopedic brace is the common non-invasive treatment to reduce the likelihood of spinal fusion surgery later. The traditional way to make such brace is inaccurate, messy, time- and money-consuming. Because of its nearly unlimited design freedom, 3D FDM-printing is regarded as the ultimate sustainable technique for producing such brace. From a materials point of view, SmartAgain® has the good fit with the mechanical property requirements of scoliosis braces. However, its fast crystallization rate often plays against the FDM-printing process, for example can cause poor layer-layer adhesion. Only when this problem is solved, a reliable brace which is strong, tough, and light weight could be printed via FDM-printing. Zuyd University of Applied Science has, in close collaboration with Maastricht University, built thorough knowledge on tuning crystallization kinetics with the temperature development during printing, resulting in printed products with improved layer-layer adhesion. Because of this knowledge and experience on developing materials for 3D printing, QuinLyte contacted Zuyd to develop a strategy for printing a wearable scoliosis brace of SmartAgain®. In the future a range of other tailor-made products can be envisioned. Thus, the project is in line with the GoChem-themes: raw materials from recycling, 3D printing and upcycling.
Currently, many novel innovative materials and manufacturing methods are developed in order to help businesses for improving their performance, developing new products, and also implement more sustainability into their current processes. For this purpose, additive manufacturing (AM) technology has been very successful in the fabrication of complex shape products, that cannot be manufactured by conventional approaches, and also using novel high-performance materials with more sustainable aspects. The application of bioplastics and biopolymers is growing fast in the 3D printing industry. Since they are good alternatives to petrochemical products that have negative impacts on environments, therefore, many research studies have been exploring and developing new biopolymers and 3D printing techniques for the fabrication of fully biobased products. In particular, 3D printing of smart biopolymers has attracted much attention due to the specific functionalities of the fabricated products. They have a unique ability to recover their original shape from a significant plastic deformation when a particular stimulus, like temperature, is applied. Therefore, the application of smart biopolymers in the 3D printing process gives an additional dimension (time) to this technology, called four-dimensional (4D) printing, and it highlights the promise for further development of 4D printing in the design and fabrication of smart structures and products. This performance in combination with specific complex designs, such as sandwich structures, allows the production of for example impact-resistant, stress-absorber panels, lightweight products for sporting goods, automotive, or many other applications. In this study, an experimental approach will be applied to fabricate a suitable biopolymer with a shape memory behavior and also investigate the impact of design and operational parameters on the functionality of 4D printed sandwich structures, especially, stress absorption rate and shape recovery behavior.
Lichtgewicht voertuigen voor stadsdistributie bestaan voor een belangrijk deel uit vezelversterkte kunststoffen zoals carbon fiber reinforced polymers. De productie hiervan is tijdrovend en recycling is maar beperkt mogelijk. Het realiseren van zero-emissie stadsvervoer in 2025 wordt met de bestaande technologie duur en niet circulair. ModuBase beoogt een nieuw recyclebaar polymeer in combinatie met een Added Manufacturing platform (3D Printen) te ontwikkelen. Hiermee wordt het mogelijk om volledig recyclebare kunststoffen 3D te printen dichtbij de montage van de voertuigen. Supply chains worden zo korter, gebruikers en ontwerpers krijgen meer ontwerpvrijheid en de grondstof is (oneindig) recyclebaar. Dit consortium maakt gebruik van een nieuw ontwikkeld thermoplastisch polymeer en gaat dit voor het eerst toepassen in 3D printing. Hiervoor is een consortium voorzien met de materiaalexpertise (DSM), 3D Printexpertise (CEAD) en werktuigbouwkundige ontwikkelexpertise (Fontys). De materialen worden uitvoerig bestudeerd voor automotive toepassingen, ontwerpregels worden opgesteld en eerste werkstukken worden geprint. Materiaaleigenschappen en recyclebaarheid na het printen worden in testopstellingen ge-evalueerd. Resultaat is een proof of concept van een vezelversterkt 3D print platform. Het betrokken industriële (automotive) cluster van Brainport wordt geïnteresseerd om met de nieuw ontwikkelde 3D printkennis prototypes voor Light Electric Vehicles onderdelen te gaan ontwikkelen en onderzoeken.
