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
This study aims to provide an in-depth characterization of the intelligent behaviour exhibited by structures fabricated using fused deposition modelling (FDM) printing technology. The primary objective is to understand the variability in the shape-morphing behaviour of additively manufactured PLA structures. A comprehensive analysis is conducted to shed light on the impact of various factors on shape transformation, encompassing both working and printing parameters. To establish the relationship between the printing and working parameters with the shape morphing characteristics, the experimental procedure employs Taguchi's method design of experiments. Notably, the study quantitatively reveals the extent of these parameters' impact on the characteristics.
The age estimation of biological traces is one of the holy grails in forensic investigations. We developed a method for the age estimation of semen stains using fluorescence spectroscopy in conjunction with a stoichiometric ageing model. The model describes the degradation and generation rate of proteins and fluorescent oxidation products (FOX) over time. The previously used fluorimeter is a large benchtop device and requires system optimization for forensic applications. In situ applications have the advantage that measurements can be performed directly at the crime scene, without additional sampling or storage steps. Therefore, a portable fiber-based fluorimeter was developed, consisting of two optimized light-emitting diodes (LEDs) and two spectrometers to allow the fluorescence protein and FOX measurements. The handheld fiber can be used without touching the traces, avoiding the destruction or contamination of the trace. In this study, we have measured the ageing kinetics of semen stains over time using both our portable fluorimeter and a laboratory benchtop fluorimeter and compared their accuracies for the age estimation of semen stains. Successful age estimation was possible up to 11 days, with a mean absolute error of 1.0 days and 0.9 days for the portable and the benchtop fluorimeters, respectively. These results demonstrate the potential of using the portable fluorimeter for in situ applications.
Lightweight, renewable origin, mild processing, and facile recyclability make thermoplastics the circular construction materials of choice. However, in additive manufacturing (AM), known as 3D printing, mass adoption of thermoplastics lags behind. Upon heating into the melt, particles or filaments fuse first in 2D and successively in 3D, realizing unprecedented geometrical freedom. Despite a scientific understanding of fusion, industrial consortium experts are still confronted with inferior mechanical properties of fused weld interfaces in reality. Exemplary is early mechanical failure in patient-specific and biodegradable medical devices based on Corbion’s poly(lactides), and more technical constructs based on Mitsubishi’s poly(ethylene terephthalate), PET. The origin lies in contradictory low rate of polymer diffusion and entangling, and too high rate of crystallization that is needed to compensate insufficient entangling. Knowing that Zuyd University in close collaboration with Maastricht University has eliminated these contradictory time-scales for PLA-based systems, Corbion and Mitsubishi contacted Zuyd with the question to address and solve their problem. In previous research it has been shown that interfacial co-crystallization of alternating depositioned opposite stereo-specific PLA grades resulted in strengthening of the interface. To promote mass adoption of thermoplastics AM industries, the innovation question has been phrased as follows: What is a technically scalable route to induce toughness in additively manufactured thermoplastics? High mechanical performance translates into an intrinsic brittle to tough transition of stereocomplex reinforced AM products, focusing on fused deposition modeling. Taking the professional request on biocompatibility, engineering performance and scalability into account, the strategies in lowering the yield stress and/or increasing the network strength comprise (i) biobased and biocompatible plasticizers for stereocomplexed poly(lactide), (ii) interfacial co-crystallization of intrinsically tough polyester based materials formulations, and (iii) in-situ interfacial transesterification of recycled PET formulations.
In dit project wordt de haalbaarheid bestudeerd voor het maken van nanoporeuze membranen met behulp van gangbare processen in de halfgeleiderindustrie. Nanoporeuze membranen bieden onder meer de mogelijkheid om op energie-efficiënte en milieuvriendelijke manier water te ontzouten of het scheiden van vluchtige componenten als alternatief voor destillatie. Recent zijn veel nieuwe nanoporeuze materialen gerapporteerd. Succesvolle toepassingen op het gebied van katalyse, sensoren en scheidingen, waaronder ook eerste voorbeelden van kleinschalige nanofiltratie, geven de potentie van dergelijke materialen aan voor een toepassing op het gebied van nanofiltratie op grotere schaal. Echter, het ontbreekt momenteel aan goede, eenvoudige methoden om deze opschaling voor ultradunne (sub-micron), nanoporeuze membranen te realiseren. In dit project zal wordt een methode bestudeerd en geïmplementeerd waarmee dit wel mogelijk is.
