The objectives of this project are (1) to reduce the excursions between real heater temperatures and the desired values, and (2) to realize cyclic production of plastic sheets on the AAA thermoforming machine. / At first, present relevant knowledge and modeling of the AAA machine are covered. A programmable pre-processing module is inserted before the heaters to prevent the input commands from delaying in heater response. The results prove that the excursions can be theoretically reduced to zero. / Based on the Terminal Iterative Learning Control (TILC) algorithm, a hybrid dual-mode cascade-loop system is designed: the inner loop monitors the real-time temperatures for PID control in Mode 0, while the outer loop reads temperatures and commands once per cycle to decide the necessity of switching mode. A more realistic version with flexible cycle length and instant response to operator's commands is also designed to simulate the real operating circumstance.

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Chapas de poli(metacrilato de metila) podem ser modificadas por meio da adição de um agente promotor de ligações cruzadas e um plastificante objetivando incrementar seu desempenho durante a termoformagem. A interação intermolecular, modificada com a adição de diferentes quantidades de um agente promotor de ligações cruzadas (TEGDMA) e pela presença de um plastificante (DOP) faz com que as macromoléculas sejam ancoradas e afastadas respectivamente. O desenvolvimento deste trabalho objetivou, avaliar as propriedades físicas, mecânicas, térmicas e o processamento via termoformagem para duas diferentes temperaturas de termoformagem em um molde cilíndrico, a uma mesma taxa de deformação e determinado a influência da formulação, para cinco chapas que se diferenciaram nas quantidades de TEGDMA e uma quantidade fixada de DOP para duas das formulações. Os resultados mostraram que há incremento na deformação com as modificações introduzidas quando comparado a uma chapa sem adição de TEGDMA ou DOP e as propriedades destas chapas como dureza superficial, módulo de rigidez e temperatura de transição vítrea apresentaram mudanças sensíveis, que caracterizam vantagens no uso dos dois componentes. / Poly(methyl methacrylate) sheets can be modified adding a cross-linking agent and a plasticizer, to increase performance during thermoforming. The intermolecular interaction modification can be achieved adding different amount of cross-linking agent (TEGDMA) and a plasticizer (DOP). They have an effect on the network polymer system improving the intermolecular interaction and increasing the macromolecular distances, respectively. The aim of this study was to prepare acrylic sheets formulations with differents amounts of TEGDMA and a fixed amount of DOP, and thermoformed using at differents process temperatures and a mould cylinder at the same strain rate. Samples were carried out and their properties physical, mechanical, thermal and thermoformability was characterized. The results have shown strain increases, changes in surface hardness, Young moduli and glass transition temperature, compared to a reference acrylic sheet.

Chapas de poli(metacrilato de metila) podem ser modificadas por meio da adição de um agente promotor de ligações cruzadas e um plastificante objetivando incrementar seu desempenho durante a termoformagem. A interação intermolecular, modificada com a adição de diferentes quantidades de um agente promotor de ligações cruzadas (TEGDMA) e pela presença de um plastificante (DOP) faz com que as macromoléculas sejam ancoradas e afastadas respectivamente. O desenvolvimento deste trabalho objetivou, avaliar as propriedades físicas, mecânicas, térmicas e o processamento via termoformagem para duas diferentes temperaturas de termoformagem em um molde cilíndrico, a uma mesma taxa de deformação e determinado a influência da formulação, para cinco chapas que se diferenciaram nas quantidades de TEGDMA e uma quantidade fixada de DOP para duas das formulações. Os resultados mostraram que há incremento na deformação com as modificações introduzidas quando comparado a uma chapa sem adição de TEGDMA ou DOP e as propriedades destas chapas como dureza superficial, módulo de rigidez e temperatura de transição vítrea apresentaram mudanças sensíveis, que caracterizam vantagens no uso dos dois componentes. / Poly(methyl methacrylate) sheets can be modified adding a cross-linking agent and a plasticizer, to increase performance during thermoforming. The intermolecular interaction modification can be achieved adding different amount of cross-linking agent (TEGDMA) and a plasticizer (DOP). They have an effect on the network polymer system improving the intermolecular interaction and increasing the macromolecular distances, respectively. The aim of this study was to prepare acrylic sheets formulations with differents amounts of TEGDMA and a fixed amount of DOP, and thermoformed using at differents process temperatures and a mould cylinder at the same strain rate. Samples were carried out and their properties physical, mechanical, thermal and thermoformability was characterized. The results have shown strain increases, changes in surface hardness, Young moduli and glass transition temperature, compared to a reference acrylic sheet.

In recent decades, a type of shape memory polymers (SMPs), namely thermoplastic shape memory polyurethane (shape memory TPU, using TPU for short) has drawn considerable attention for its excellent shape memory properties, versatile structure and good mechanical properties. Most recently, shape memory TPU films are envisioned as a replacement for automobile exterior and interior decorative applications in the forms of laminates through in-mold forming (IMF) process. However, for a better dimensional control of laminates during the IMF, the shape memory effect of laminates needs to be controlled such that its behaviour is only noted at the time of damage and is not an instigator of delamination. In order to investigate the shape memory behavior of TPU based laminates after they had experienced normal processing such as by thermoforming, the influence of different properties were examined, including TPU film modulus, substrate used (polypropylene (PP) versus acrylonitrile butadiene styrene (ABS)), ambient temperature and the extent of deep draw, on the recovery behaviour. The study included analyses through both experimental and modelling methods. A novel thermo-mechanical cycling method was proposed to examine the shape memory property of the TPU based laminates under stretching/bending conditions more similar to thermoforming. Recovery based on this method was defined using new terms of angle recovery ratio and recovery rate. The new test examined recovery at 15oC, 45oC and 65oC; these ambient conditions were selected above and below the glass transition temperature of the TPU. Results showed that the final angle recovery ratio and recovery rate of deformed laminates based on a new commercial class of TPU shape memory polymer increased with its modulus from low to high. Substrates of higher modulus (ABS) lowered the final angle recovery ratio and recovery rate achievable for a formed laminate. Furthermore, increasing the ambient temperature increased both the final angle recovery ratios and recovery rates of formed TPU based laminates. As the extent of draw changed from 6 mm to 10mm, the final angle recovery ratios and recovery rates of formed laminates increased for all TPU films but this trend was reversed when the draw further increased beyond 10mm. The laminate system was subsequently modelled using a linear viscoelastic (SLV) constitutive model to analyze the stress-strain relationship between the substrate and TPU film layers during recovery. A model parameter related to stress transfer across the interface of these two polymer layers was fitted to the experimental results with an excellent degree of fit. The model results fitted well with experimental data and showed that the final angle recovery ratios of formed TPU laminates were mainly dependant on the moduli of TPU and substrates layers as well as the stress transfer ratio through the adhesive layer (TR). The influence of the adhesive layer was not a trivial variable in the recovery nature of the laminate. The influence of ambient temperature on the recovery behaviour of laminates was mainly due to the temperature-dependent and time-dependent Young’s modulus and relaxation time of both TPU and substrate layers. Higher relaxation times for the TPU layer or lower relaxation time for the substrate layer yielded a higher recovery rate for the laminate during the first five minutes of recovery. / Thesis / Master of Applied Science (MASc) / Special classes of Polyurethanes exhibit a strong memory of their formed shape, and hence are called shape memory polymers. Films made of these polymers are envisioned as a replacement for decorative applications in automobiles if their forming behaviour is understood. This thesis project looked at how much of that memory was preserved as a laminate after thermoforming by looking at the effect of film stiffness, backing material used (polypropylene (PP) versus acrylonitrile butadiene styrene (ABS)), ambient temperature and the extent of deep draw, using both experimental and modelling methods. Results showed that through using stiffer films, weaker substrates, high ambient temperature or an optimal extent of deep draw, recovery behavior of the shape memory polymer in these laminates can be improved, and vice versa.

No / Thermoforming is widely employed in industry for the manufacture of lightweight, thin-walled products from pre-extruded plastic sheet and its largest application is in packaging. Over many years attempts have been made to simulate the process and thereby exploit modern computational tools for process optimisation. However, progress in this area has been greatly hampered by insufficient knowledge of the response of polymer materials under thermoforming conditions and an inability to measure this and other processing phenomena accurately. In recent years some address has been made to these problems through advances in measurement technologies, and in particular, the development of high speed, high strain, biaxial testing machines that are designed to replicate the conditions in thermoforming processes. In this work the development of an advanced finite element-based thermoforming process simulation is presented. At its heart is a sophisticated large strain thermally coupled (LSTC) material model for polypropylene, which has been developed after several years of research and is founded directly on biaxial test results at elevated temperatures. This material model has been demonstrated to provide an excellent fit to the biaxial data and to offer a very stable computational platform for the process simulation.The performance of the working simulation was validated through comparison with matching experimental test results, and this enabled investigation of the sensitivity of the process output (in the form of part wall thickness distribution) to changes in a range of other processing parameters. This work confirmed that the process is most sensitive to the parameters controlling plug/sheet contact friction. Heat transfer parameters were also shown to be significant and the requirement for the model to be fully thermo-mechanically coupled has been clearly established.

Vacuum forming is a popular, cost effective method amongst large and small scale applications. The method is used to mold a material to the surface of a mold/pattern in order to create a negative copy for reproduction or an object in positive form. The prototype vacuum forming system developed and documented herein is of a membrane-seal type that consists of three (3) principle parts: radial platen, Hinged Frame and Platen Support Assembly, and a PVC surge tank. Each part is described in detail through design, manufacturing, and testing processes. The design supports functional versatility, small scale molding, and uses readily available materials. Functional prototype testing was performed with the thermoplastic KYDEX® and multiple objects for mold examples. Results include successful proof of concept, design pros and cons, and findings based on functional testing.

Grâce aux technologies de la microfluidique (i.e. la manipulation d'un fluide dans un système ayant une dimension caractéristique sub-millimétrique), il est possible d'imaginer l'intégration de l'ensemble des fonctions ordinairement réalisées en laboratoire dans un système miniaturisé, réalisant ainsi un laboratoire sur puce. Cela peut ainsi permettre d'allier efficacité et bas-coût requis pour la réalisation de dispositif de diagnositcs médicaux utilisable en dehors d'infrastructure médicalisée, souvent appelés systèmes Point-of-Care. Pour la réalisation d'un tel dispositif, il semble important de concevoir l'intégration des différents composants du système d'une façon cohérente, et en prenant en compte l'ensemble des contraintes imposées par l'application finale ciblée. Le travail effectué au cours de cette thèse a ainsi été réalisé dans l'optique de proposer une réponse à cette problématique d'intégration dans le cadre du développement d'un système microfluidique de diagnostic Point-of-Care basé sur une réaction d'amplification d'ADN isotherme LAMP. Afin de pouvoir proposer un système bon marché et dont l'industrialisation est aisée, nous avons fait appel à l'utilisation du papier comme support et au thermoformage comme moyen de production. En effet à la fois l'industrie papetière et le procédé de thermoformage sont d'ores et déjà existant et proposent des fabrications en série. De plus, le faible coût du matériau et du procédé en question permettent d'envisager un dispositif final à bas-coût. Afin de pouvoir effectuer et détecter la réaction de LAMP la présence de fonctions actives telles qu'un chauffage et un outil de détection est nécessaire. Pour ces dernières, l'intégration a été réalisée par procédé sérigraphique. Le chauffage est effectué par effet Joule grâce au dépôt d'une couche d'encre conductrice à base de carbone. La détection est quant à elle faite par méthode potentiométrique, à l'aide d'électrode couverte de polyaniline. Il sera également montré que l'utilisation de ces méthodes de fabrication est pertinente en termes d'intégration car elles permettent une superposition des différentes fonctions actives, mais également leur intégration directement dans le système microfluidique. / Developments of microfluidics - the study of flows at the sub-millimetric dimensions - have made possible the integration of most of the macroscopic functions of laboratory fluidic systems in a miniaturized system, thus realizing a lab on a chip. This allows the conception of low cost, sensitive and efficient medical diagnostic device usable outside of a medical infrastructure. Such devices are called Point-of-Care (PoC) systems. The design and fabrication of such devices requires an elaborated and coherent integration that takes into account all the constraints imposed by the targeted final application.The work reported here, and performed during the PhD internship, is focused on the study of the concept and development of the integration of a PoC device based on the isothermal LAMP (Loop mediated AMPlification) reaction for the molecular analysis of DNA. In order to offer a cheap and easily industrialized system, we investigate the use of paper as the chip material and thermoforming as the mean to build the channels. These two techniques are currently used in the industry and their adaptation to the fabrication of such devices is easy and low-cost. In order to perform a LAMP reaction, specific functions such as a heating and a detection system are required. The integration of these functions was carried out using screen printing technology. Heating is done by Joule effect using a layer of carbon-based conductive ink. Detection is performed by a potentiometric method, using polyaniline-covered electrodes. It is shown that this approach is compatible with integration when the screen-printing layers are superposed. Besides they can be printed before thermoforming, resulting in a highly integrated system.

Das Thermoformen, umgangssprachlich auch als Tiefziehen bezeichnet, stellt neben dem Spritzguss ein zentrales Verfahren zur Herstellung formstabiler Verpackungen aus Folien dar. Vorrangig werden Produkte des alltäglichen Bedarfs wie Verpackungen für Lebensmittel, Pharmazeutika oder technische Produkte hergestellt. Aber auch technische Bauteile wie z.B. Gehäuse von Elektrogeräten, Verkleidungsteile von Fahrzeugen oder zunehmend auch Komponenten für die Biotechnologie, bspw. Gehäuse oder permeable Membranen. Allein die weltweite Nachfrage nach formstabilen Kunststoffverpackungen lag im Jahr 2010 bei einem Marktvolumen von 144 Mrd. $. Bei einer jährlichen Wachstumsrate von durchschnittlich 6% wird erwartet, dass die Nachfrage bis zum Jahr 2016 auf bis zu 200 Mrd. US$ ansteigt (Aranca 2012). In Europa werden jährlich ca. 12 Mrd. thermogeformte Verpackungen hergestellt. Der Anteil thermogeformter Produktverpackungen lag dabei im Jahr 2011 bei ca. 10%. Durch die weltweit steigende Nachfrage nach Kunststoffverpackungen, insbesondere aber durch die ökonomisch vorteilhaften Eigenschaften des Thermoformprozesses gegenüber anderen Herstellungsverfahren der Kunststoffverarbeitung, wird erwartet, dass der Anteil thermogeformter Produktverpackungen bis zum Jahr 2019 auf ein Marktvolumen von 17 Mrd. $ anwächst (ReportsnReports 2012 & ReportLinker 2014). [... aus der Einleitung]