Dissertations / Theses on the topic 'Intelligent Polymers'
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Moulton, Brian D. ""Intelligent" Design of Molecular Materials: Understanding the Concepts of Design in Supramolecular Synthesis of Network Solids." [Tampa, Fla.] : University of South Florida, 2003. http://purl.fcla.edu/fcla/etd/SFE0000603.
Full textGottlieb, Ronny, and Karl-Friedrich Arndt. "Intelligente Werkstoffe - Vom Makromolekül zum intelligenten Material." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2007. http://nbn-resolving.de/urn:nbn:de:swb:14-1188378259921-41093.
Full textUmgebungssensitive Polymere ändern in Abhängigkeit von Umgebungsbedingungen, wie zum Beispiel dem Licht, der Temperatur, dem pH-Wert oder der Konzentration einer zweiten Komponente neben dem Polymer, drastisch ihre Molekülgestalt. Vernetzt und in Wasser gequollen, bilden sie sogenannte smarte Hydrogele. Dabei werden die Besonderheiten eines Makromoleküls, dessen Eigenschaften durch die Umgebung beeinflusst werden, auf ein polymeres Material übertragen. Dies kann ein großer Körper, eine dünne Schicht oder ein Nanopartikel sein. Das Volumen der smarten Hydrogele kann zwischen zwei Zuständen geschaltet werden. Dabei können die Hydrogele wie Aktoren eine Kraft ausüben. Da das Schalten durch die Umgebung stimuliert wird, sind sie als Sensoren verwendbar. Die Polymerstrukturen sind miniaturisierbar, sodass smarte Hydrogele als Komponenten in Mikrosystemen angewendet werden können. Zum Beispiel werden die Partikel zur kontrollierten Abgabe von Arzneimittelwirkstoffen verwendet
Motornov, Mikhail. "Fabrication and Study of Switchable Polymer Layers with Hydrophobic/Hydrophilic Behavior." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2004. http://nbn-resolving.de/urn:nbn:de:swb:14-1101369711031-72233.
Full textHart, Sean Michael. "Intelligent Processing of PMR-15." W&M ScholarWorks, 1992. https://scholarworks.wm.edu/etd/1539625733.
Full textNgatchou, Patrick. "Intelligent techniques for optimization and estimation /." Thesis, Connect to this title online; UW restricted, 2006. http://hdl.handle.net/1773/5827.
Full textYu, Dingwen. "Development of an intelligent design tool for polymer screw extruders." Thesis, Nottingham Trent University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324589.
Full textMarchant, Maïté. "Modélisation multi-échelles des systèmes nanophotoniques à base de matériaux intelligents." Thesis, Clermont-Ferrand 2, 2014. http://www.theses.fr/2014CLF22449.
Full textMany engineering applications involve stimuli-responsive materials that can change their shape under the action of an external stimulus. It is in this context that this project takes place. Thanks to a multidisciplinary environment with the association of two lines of research of the Institut Pascal: the Mechanical area (Mechanic, Materials and structure) and the Photonic area (Nanostructures and Nanophotonics), this PhD perfectly fits with the “Materials and multi-scale Modeling” transversal action of the laboratory. The first part of this work relies on an experimental system developed by an American team [Chang_10] which allows to measure the pH of a solution without contact, making use of its photonic characteristics. This system is composed of a hydrogel network fixed on a rigid substract. A numerical model is developed in order to simulate its behavior and optimize the hydrogel network with a view to applications in the medical domain. The second part of this PhD is related to the development of a theory on the mechanical behavior of photo-sensitive polymers. The aim is to establish a link between the material deformation and the light intensity. The obtained results are compared to experimental ones from literature. The interaction influence of the azobenzenes molecules on the material strain is studied
Ramgobin, Aditya. "Synthèse et conception de retardateurs de flamme intelligents." Thesis, Lille 1, 2019. http://www.theses.fr/2019LIL1R045/document.
Full textPolymeric materials have been increasingly used as replacement for other types of materials such as ceramics or metals. However, most polymers have a serious drawback: they need to be fire retarded. Nevertheless, thanks to advanced research in the field, high performance materials that resist high temperatures and fire scenarios have been developed. While these materials have extremely enviable properties, they are also very expensive. The aim of this PhD is to understand the fire behavior of high-performance polymers and design fire retardants that would mimic these high-performance materials under extreme heat or fire. To do so, the thermal and fire behavior of three high performance materials were studied: polyetheretherketone (PEEK), polyimide (PI), and polybenzoxazole (PBO). Their thermal decomposition pathways were evaluated thanks to high temperature analytical techniques like pyrolysis-GC/MS and TGA-FTIR. Model based kinetics of the thermal decomposition of these polymeric materials were also elucidated by using dynamic TGA under three different atmospheres (nitrogen, 2% oxygen, and air). These provided insight regarding the thermal behavior high performance polymers, which were used to conceptualize novel potential fire retardants. Therefore, a series of fire retardants that have demonstrated similar behaviors as high performance polymers in fire scenarios were synthesized. These fire retardants include a Schiff base: salen and its derivatives, as well as some of their metal complexes. The thermal behavior and fire performances of these fire retardants were evaluated in two polymeric materials using a relatively low loading (< 10 wt%): thermoplastic polyurethane, and polyamide 6. While some of the fire retardants had little effect, in terms of fire retardancy, some candidates showed a significant improvement in terms of peak of heat release rate. This reverse approach towards designing fire retardants has shown some promise and can be used as a complementary method for the design of high-performance materials at lower cost
Lu, Jianbo. "Development of intelligent textiles from conductive polymer composites (CPC) for vapour and temperature sensing." Lorient, 2009. http://www.theses.fr/2009LORIS149.
Full textJamal, Al Dine Enaam. "Synthèse et caractérisation des nanoparticules intelligentes." Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0054/document.
Full textOne of the major challenges in nanomedicine is to develop nanoparticulate systems able to serve as efficient diagnostic and/or therapeutic tools against sever diseases, such as infectious or neurodegenerative disorders. To enhance the detection and interpretation contrast agents were developed to increase the signal/noise ratio. Among them, Superparamagnetic Iron Oxide (SPIO) and Quantum Dots (QDs) nanoparticles (NPs) have received a great attention since their development as a liver contrasting agent 20 years ago for the SPIO. Furthermore, their properties, originating from the nanosized dimension and shape, allow different bio-distribution and opportunities beyond the conventional chemical imaging agents. The opportunity to coat those biocompatible NPs by a polymer shell that can ensure a better stability of the materials in the body, enhance their bio-distribution and give them new functionalities. It has appeared then that they are very challenging for medicinal applications. In this work, we have developed new responsive SPIO and QDs based NPs that are able to carry the anticancer drug doxorubicin (DOX) and release it in physiological media and at the physiological temperature. Two families of NPs were synthesized, the first one consist in superparamagnetic Fe3O4 NPs that were functionalized by a biocompatible responsive copolymer based on 2-(2-methoxy) ethyl methacrylate (MEO2MA), oligo (ethylene glycol) methacrylate (OEGMA). The second family consists in the ZnO NPs coated by the same copolymer. For the first time, P(MEO2MAX-OEGMA100-X) was grown by activator regenerated by electron transfer–atom radical polymerization (ARGET-ATRP) from the NPs surfaces by surface-initiated polymerization. The core/shell NPs were fully characterized by the combination of transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and by the physical properties of the nanostructures studied. We demonstrate the efficiency of the ARGET-ATRP process to graft polymers and copolymers at the surface of Fe3O4 and ZnO NPs. The influence of the polymer chain configuration (which leads to the aggregation of the NPs above the collapse temperature of the copolymer (LCST)) was studied. We have demonstrated that the magnetic properties of the core/shell Fe3O4-based nanostructures were only influenced by the amount of the grafted polymer and no influence of the aggregation was evidenced. This simple and fast developed process is efficient for the grafting of various co-polymers from any surfaces and the derived nanostructured materials display the combination of the physical properties of the core and the macromolecular behavior of the shell. The drug release experiments confirmed that DOX was largely released above the co-polymer LCST. Moreover, the cytocompatibility test showed that those developed NPs do not display any cytotoxicity depending on their concentration in physiological media. From the results obtained, it can be concluded that the new nanomaterials developed can be considered for further use as multi-modal cancer therapy tools
Hespel, Louise. "Nouveaux systèmes micellaires intelligents à partir d'huile de lin : synthèse, comportements physico-chimiques et encapsulation." Phd thesis, INSA de Rouen, 2013. http://tel.archives-ouvertes.fr/tel-00924698.
Full textCottinet, Pierre-Jean. "Actionnement et récupération d'énergie à l'aide de polymères électro-actifs." Lyon, INSA, 2010. http://theses.insa-lyon.fr/publication/2010ISAL0094/these.pdf.
Full textPolymers have attractive properties compared to inorganic materials. They are lightweight, inexpensive, fracture tolerant, pliable, and easily processed and manufactured. They can be configured into complex shapes and U1eir properties can be tailored according to demand. With the rapid advances in materials used in science and tecl1nology, various materials with Intelligence embedded at the molecular level are being developed at a fast pace. These smart materials can sense variations in the environment, process the information, and respond accordingly. Shape-memory alloys, piezoelectric materials, etc. Fall in tt1is category of intelligent materials. Polymers that respond to external stimuli by changing shape or size have been known and studied for several decades. They respond to stimuli such as an electrical field, pH, a magnetic field, and light. These intelligent polymers can collectively be called active polymers. One of the significant applications of these active polymers is found in biomimetics-the practice of taking ideas and concepts from nature and implementing them in engineering and design. Various machines that imitate birds, fish, insects and even plants have been developed. With the increased emphasis on "green" technological solutions to contemporary problems, scientists started exploring the ultimate resource--nature-for solutions that have become highly optimized du ring the millions of years of evolution. The objectives of the work reported in the present document are threefold. The first aim consists in electrical and mechanical characterization of polymer and composites, realized in the laboratory with matrix of polyurethane and P(VDF-TrFE-CFE). The others two parts concerns the study of a new electrostrictive polymer composite (EPC) to be used in actuators and mechanical energy harvesters
Jannot, Marion. "Polymères nanocomposites multifonctionnels. Impact sur les propriétés mécaniques de polymères à mémoire de forme." Electronic Thesis or Diss., Sorbonne université, 2018. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2018SORUS549.pdf.
Full textThese works based on the developments of polymer nanocomposites illustrate the possibility of creating shape memory hybrid materials from a semi-crystalline thermoplastic elastomer copolymer, the poly(ethylene – vinyl acetate). Amongst the different approaches which exist to obtain thermo-responsive shape memory polymers, we chose to elaborate chemically crosslinked networks in attendance of an inorganic component as silicon oxo-polymer or titanium oxo-polymer. Tensile test showed that hybrid materials with titanium oxo-polymer provide an important reinforcement. At room temperature and at 100 °C, the elastic modulus of the material increase more than 3.8 times and 57 times in comparison to organic reference material crosslinked by peroxides. As the reference material, all nanocomposites display shape memory properties under appropriate conditions of time, stress and temperature. With titanium oxo-polymer, the dynamic iono-covalent nature of the hybrid interface bring news properties. Thermadapt nanocomposite materials are obtained. The use of an organic – inorganic hybrid material enable by tuning nanostructuration and nature of the hybrid interface to obtain multifunctional materials with shape memory properties, reprocessability, recyclability and thermally induced healing properties
Olivier, Boissière. "Étude de polymères répondant à deux stimuli." Thèse, Université de Sherbrooke, 2015. http://hdl.handle.net/11143/6007.
Full textAbolfathi, Peter Puya. "Development of an Instrumented and Powered Exoskeleton for the Rehabilitation of the Hand." Thesis, The University of Sydney, 2008. http://hdl.handle.net/2123/3690.
Full textAbolfathi, Peter Puya. "Development of an Instrumented and Powered Exoskeleton for the Rehabilitation of the Hand." University of Sydney, 2008. http://hdl.handle.net/2123/3690.
Full textWith improvements in actuation technology and sensory systems, it is becoming increasingly feasible to create powered exoskeletal garments that can assist with the movement of human limbs. This class of robotics referred to as human-machine interfaces will one day be used for the rehabilitation of paralysed, damaged or weak upper and lower extremities. The focus of this project was the development of an exoskeletal interface for the rehabilitation of the hands. A novel sensor was designed for use in such a device. The sensor uses simple optical mechanisms centred on a spring to measure force and position simultaneously. In addition, the sensor introduces an elastic element between the actuator and its corresponding hand joint. This will allow series elastic actuation (SEA) to improve control and safely of the system. The Hand Rehabilitation Device requires multiple actuators. To stay within volume and weight constraints, it is therefore imperative to reduce the size, mass and efficiency of each actuator without losing power. A method was devised that allows small efficient actuating subunits to work together and produce a combined collective output. This work summation method was successfully implemented with Shape Memory Alloy (SMA) based actuators. The actuation, sensory, control system and human-machine interface concepts proposed were evaluated together using a single-joint electromechanical harness. This experimental setup was used with volunteer subjects to assess the potentials of a full-hand device to be used for therapy, assessment and function of the hand. The Rehabilitation Glove aims to bring significant new benefits for improving hand function, an important aspect of human independence. Furthermore, the developments in this project may one day be used for other parts of the body helping bring human-machine interface technology into the fields of rehabilitation and therapy.
Carré, Méline. "Développement de nouveaux polymères fonctionnels et intelligents, ayant des propriétés optiques modifiables sur demande." Thesis, Mulhouse, 2021. http://www.theses.fr/2021MULH4570.
Full textThermoplastics are a class of polymers widely used in industry because of their low processing costs. Pellets of thermoplastic are heated and then the melted thermoplastic can take every shape. Several methods can be used like injection molding, extrusion, thermoforming or 3D printing to give the shape. No solvent is required during the process. The interesting characteristic is that thermoplastics are recyclable, unlike the other class of polymer called thermoset. In fact, the material could be reheated to be remolded several times without affecting the chemical structure. All of these attract the interest of several sectors like medicine, aeronautics or automobile. The aim of this work is to develop smart thermoplastics with new additional properties. Additives are incorporated into the thermoplastic to give stimuli responsive properties. Usually additives are mixed with resin and the ink is applied to the surface or thermoplastics are solved to be mixed with additives. In this study, we want to avoid coating and solvent in order to obtain intrinsic properties by cleaning way. Therefore, additives are mixed with melted thermoplastic. The difficulty is to incorporate the additive and mold thermoplastics at high temperature (from 150 °C to 300 °C) without damaging additives
Motornov, Mikhail. "Herstellung und Untersuchung schaltbarer Polymerschichten mit hydrophobem, hydrophilem Charakter (Fabrication and study of switchable polymerlayers with hydrophobic, hydrophilic behavior) /." [S.l. : s.n.], 2004. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB11513723.
Full textDobiáš, Vojtěch. "Senzor kvality prostředí potravinového obalu." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2021. http://www.nusl.cz/ntk/nusl-449725.
Full textCsetneki, Ildiko. "Kolloid polimer gélek szerkezetének és tulajdonsagainak kapcsolata : Szabalyoshato permeabilitasu membran kontrollalhato nyito-zaro mechanizmussal." Université Louis Pasteur (Strasbourg) (1971-2008), 2006. http://www.theses.fr/2006STR13135.
Full textAtieh, Mirna. "Contribution à la conception d'une prothèse de main communicante et "intelligente"." Rennes, INSA, 2008. http://www.theses.fr/2008ISAR0002.
Full textThis work joins within the framework of the technical helps the handicapped persons, more exactly, the amputees of upper limbs. It is about prosthesis of "intelligent" and communicating hand controlled by its carrier and which will be the myoelectric hand. In this thesis, we schematize the different movements of the prosthesis by an automaton which describes the functioning of this system. A part of our project lays on studying the existing hand prosthesis in order to improve their functionalities, their reliability at the produced signals acknowledgment, their ergonomics and, in particular, their acceptability by handicapped persons. We offer, in the present thesis, an intelligent communicating protocol allowing correlation between the prosthesis and the handicapped person. Then, we accomplish a program of simulation to validate our protocol, with real EMG signals. We realise also a second validation by using an electronic card of acquisition on which we established our program
Mwita, Wambura Mwiryenyi. "Development and testing an intelligent hybrid polymeric composite beam with healing ability embedded with Ni-Ti shape memory alloy." Thesis, Cape Peninsula University of Technology, 2010. http://hdl.handle.net/20.500.11838/1251.
Full textHybrid polymeric composites (HPC) are widely used for the design of aerospace, automobile and civil engineering structures. One of the major challenges posed by these materials and structures is their brittle nature. When subjected to impact and dynamic loads, the polymeric composite structures undergo micro cracking. The cracks coalesce, propagate and can lead to catastrophic failure of the material and structures. In this thesis, an intelligent hybrid polymeric composite (IHPC) beam with healing ability was developed and tested. The IHPC beam developed consisted of a 3% prestrained 1mm diameter Ni-Ti shape memory alloy (SMA) wire actuator embedded in the polymeric host matrix. The function of the embedded Ni-Ti shape memory alloy was to enhance intelligence and healing ability to the IHPC beam. Upon electric current resistance heating, the Ni-Ti SMA actuator responds by contracting as a result of detwinned martensite → austenite phase transformation. Contraction of the SMA in the IHPC beam was utilized to stiffen and enhance healing by retarding crack growth and recovery of the strain induced in the loaded IHPC beam. This can result to increase of the flexural stiffness EI (defined as the product of the Young’s Modulus E of the material and the moment of inertia I of the geometry of the beam) and mode I fracture stress intensity factor KIC of the IHPC beam. One (1) mm diameter Ni-Ti SMA wire was used in the experimental work in this thesis. The wire was cut into 35 pieces, 200 mm long each. Ni-Ti SMA wires were heated in the furnace to a temperature of 250ºC for ten (10) hours then were left to cool in the ambient air. The heat treatment was aimed to release any residual stress and to stabilize the austenite start (AS) and austenite finish (Af) transformation temperatures of the Ni-Ti SMA. After heat treatment, the Ni-Ti SMA wires were prestrained by 3% (based on a gauge length of 150mm) on a tensile testing machine. Prestraining of the Ni-Ti SMA wires was aimed to induce detwinned martensite volume fraction in them hence increasing the transformation strain and recovery force of the Ni-Ti SMA actuator. Intelligent hybrid polymeric composite (IHPC) beams and polymeric virgin (PV) beams, all of dimensions 150mmx25mmx10mm were manufactured by casting 60D polyurethane thermosetting epoxy resin in a silicon mould. transformation strain and recovery force of the Ni-Ti SMA actuator.
De, Smet Lieselot. "Création de systèmes polymères intelligents utilisant le cyclobis(paraquat-p-phénylène) et le cyclobis(paraquat-4,4'-biphénylène)." Thesis, Lille 1, 2020. http://www.theses.fr/2020LIL1R006.
Full textThe development of smart or intelligent polymeric materials has gained a lot of attention over the past decades. Smart materials are described as materials that are capable of altering their properties and functions in response to small external environmental changes such as fluctuations in temperature. Within this rapidly advancing field, supramolecular chemistry, including host-guest complexation, has emerged as a powerful tool for the creation of these responsive materials due to their dynamic, reversible and adaptive nature towards external stimuli. These host-guest inclusion complexes consist mostly of a macrocyclic host molecule which can interact in a highly controlled and selective manner with one or more smaller guest molecules, via both random non-covalent interactions and specific three-dimensional spatial arrangements. The integration of these dynamic supramolecular assemblies into conventional polymer chemistry through the incorporation of either the macrocyclic host or, mostly, the electron rich guest has allowed us to develop the next generation advanced materials in a less time-consuming way. In this PhD thesis macrocyclic host molecule cyclobis(paraquat-p-phenylene) and cyclobis(paraquat-4,4’-biphenylene) were incorporated in hydrophilic polymer systems (homopolymers, hydrogels) in a reversible manner. For thermoresponsive hydrogel systems, it was shown that they were able to remember how long they were exposed to a certain external temperature change. The complexation of these cyclophanes are accompagnied with a visible color change allowing the use of these materials for sensor applications
Tirado, Viloria Patricia Carolina. "New saloplastic biomaterials based on ultracentrifuged polyelectrolyte complexes." Thesis, Strasbourg, 2012. http://www.theses.fr/2012STRAF034.
Full textThis work was aimed to the develop of a new kind of materials of polyelectrolytes complexes. These materials were obtained by the ultracentrifugation of complexes either of natural or synthetic origin. The polyelectrolytes systems as well as the conditions under which these materials could be obtained, followed by the selection of the optimal system to further studies was described. PAA/PAH CoPECs was chosen as synthetic model systems and its physiochemical properties (composition, structure and mechanical properties) were here deeply described. We demonstrated that the composition, structure and mechanical properties can be controlled by changing the assembly conditions (pH, concentration of the polyelectrolytes, [NaCl], speed and order of addition). Moreover, the environmental conditions ([NaCl] and pH) were also used to control the porosity and pores size of the PAA/PAH CoPECs. Finally their ability to serve as scaffold for enzyme immobilization was also studied. We optimized the assembly conditions to keep the maximum of the activity. We also demonstrated that the CoPECs structure provides the stabilization in long term as well as the protection of the enzyme from high temperature. Thus, PAA/PAH CoPECs is a potential and suitable candidates as scaffold for tissue engineering and for the immobilization of enzymes
Claracq, Jérôme. "Comportement viscoélastique de fluides magnétorhéologiques." Pau, 2001. http://www.theses.fr/2001PAUU3026.
Full textSchäfer, Christian Gerhard [Verfasser], Matthias [Akademischer Betreuer] Rehahn, Markus [Akademischer Betreuer] Biesalski, and Rudolf [Akademischer Betreuer] Zentel. "Stimuli-Responsive Polymer-Opalfilme: Intelligente Materialien für optische Sensoranwendungen und Sicherheitsmerkmale / Christian Gerhard Schäfer. Betreuer: Matthias Rehahn ; Markus Biesalski ; Rudolf Zentel." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2016. http://d-nb.info/111214207X/34.
Full textKumar, Bijandra. "Development of smart textiles with low environmental footprint from Conductive polymer nanoComposites." Lorient, 2010. http://www.theses.fr/2010LORIS195.
Full textThis research work concerns the investigation and development of innovative eco-friendly smart multi-reactive textiles made of Conductive Polymer nanoComposite (CPC) within the frame of the European Union Commission funded project entitled “INTELTEX”. Multiwalled Carbon Nanotubes (CNT) have been used as conductive nanofiller to create conductive networks within both synthetic and bio-sourced polymer matrices. The ability of CPC thin films based sensor to detect Volatile Organic Compound (VOC) has been investigated by exposing them to a wide set of solvent vapours. Novel strategies have been introduced to fabricate vapour sensor with controlled hierarchical condictive architecture. The sensors developed were found to have a high potential to detect as well as to discriminate the studied vapours. In a second part the knowledge developed with CPC thin film was transferred to both mono-phasic and bi-phasic conductive textiles, which were demonstrated to be sensitive to vapours and temperature. In particular novel bi-phasic CPC textiles structured using double percolation were found to exhibit a sharp positive temperature coefficient (PTC) characteristic in the range 30 - 60°C. In the last part it has been shown that eco-friendly matrices could be proposed in substitution of synthetic polymers to decrease their environmental footprint. Finally, it has been demonstrated that CNT based CPC had a high potential as smart material to develop multi-reactive smart textile for vapour and temperature sensing
Jean-Mistral, Claire. "Récupération d'énergie mécanique par polymères électroactifs pour microsystèmes autonomes communicants." Phd thesis, Grenoble 1, 2008. http://tel.archives-ouvertes.fr/tel-00356265.
Full textLes polymères électroactifs incluent la famille électronique (piézoélectrique, diélectrique...) et la famille ionique (IPMC, ionic gels...). Grâce à un état de l'art complet, six types de polymères ont été sélectionnés, modélisés analytiquement (couplage électromécanique) et caractérisés. De cette première partie comparative ressortent les polymères diélectriques à la forte densité d'énergie récupérable (1.5J.g-1).
La seconde partie de ce travail de thèse concerne la mise en place d'un modèle analytique électro-mécano-thermique le plus fiable possible et adaptable à tous types de structures et de sollicitations. Pour ce faire, une large campagne de mesures électriques et mécaniques a été opérée afin de déterminer finement le comportement physique du matériau, les variations des paramètres intrinsèques et les pertes associées. Ce modèle analytique est validé par une série de tests sur des cas simples de structures.
La dernière partie de ce travail de thèse concerne le développement d'une application novatrice : la récupération d'énergie mécanique au niveau du genou lors de la marche humaine. Le convertisseur a été dimensionné grâce au modèle développé, puis testé in situ. Finalement, des pistes pour la gestion électrique autonome de l'application sont proposées.
Brunner, Birgit M. "Untersuchungen zur inneren Struktur von Hydrogelen aus N-Isopropylacrylamid mittels statischer Lichtstreuung." [S.l. : s.n.], 2005. http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-24744.
Full textCayla, Aurélie. "Élaboration de détecteurs souples de température : mise en oeuvre et caractérisation de multifilaments à base de polymères immiscibles chargés en nanotubes de carbone." Thesis, Lille 1, 2010. http://www.theses.fr/2010LIL10086/document.
Full textThis study is a part of the European research project INTELTEX (“Intelligent multireactive textiles Integrating nano-filler based CPC-fiber”) of the Sixth Framework Programme for Research and Technological Development. The elaboration of a textile sensors is ensured by the incorporation of carbon nanotubes (CNT) in one or more polymers. The final goal of this work is to integrate in Personal Protective Equipment (PPE) for fire-fighters, a new textile composite based on the use of innovative nanofillers enables them to be alerted at a critical elevation of the surrounding temperature. The realisation of this sensor requires the preparation of a biphasic Conductive Polymer Composite (CPC), where the two polymers have farther melting temperatures and one of which corresponds to the wished detection temperature. The CNT are introduced in the phase which is sensible to the temperature elevation (Polycaprolactone (PCL)) and protected by the second polymer whose melting temperature is higher (Polypropylene (PP)). For our application, an interpenetration of two phases (co-continuous morphology) and a selective localization of CNT in the PCL are privileged to obtain a good electrical conductivity. Once the development step of the biphasic conductive multifilament (by melt spinning) reached, the yarn is embedded in an instrumented woven structure, which permits to record the electrical signal. The presence of an effect of Positive Temperature Coefficient (PTC) allows the detection at the melting temperature of PCL (58°C). The firsts prototypes studied under conditions closer to the reality show the reproducibility so that very promising results
Tirado, Viloria Patricia Carolina. "Nouveaux biomatériaux saloplastiques basés sur des complexes de polyélectrolytes ultracentrifugés." Phd thesis, Université de Strasbourg, 2012. http://tel.archives-ouvertes.fr/tel-00788462.
Full textViallon, Maud. "Réalisation et caractérisation de membranes polymères microstructurées capables de moduler leurs propriétés de réflexion dans le domaine du moyen infrarouge : application aux textiles pour le confort thermique." Thesis, Lille 1, 2017. http://www.theses.fr/2017LIL10105.
Full textThe goal of this thesis is the manufacturing of polymer membranes that can be complexed to a textile to improve the thermal comfort felt. They must be able to dynamically modulate their optical properties in the mid-infrared (MIR) according to the environmental conditions.The first part of this work presents the theoretical notions related to thermal comfort and both physical mechanisms hydric and thermal transfers through the textile membranes. A state of the art makes it possible to identify the existing technologies. The concept of photonic crystals and their application in the field of infrared medium are presented. This part ends with the establishment of specifications for the design of a structured polymer membrane using the principle of photonic crystals to modulate the interaction of human thermal radiation.The second part of this work describes the method of finite differences in time domain simulation (FDTD) used to predict the optical properties of micro-structured membranes as function of their geometric characteristics. A first realization in polycrystalline silicon authorizes the validation of the numerical model calibration as well as the protocol of the infrared characterization. The manufacturing process uses cleanroom technologies from microelectronics and microsystems.The last part of this work is devoted to the study by FDTD of microstructured polymer membranes from the previously calibrated 'in-silico' model. This study makes it possible to define geometrical parameters able to modulate the reflection of the infrared having a wavelength between 5 and 15 microns. A manufacturing process is developed which makes it possible to realize self-supporting structured membranes to the appropriate dimensions
Hashemi, Sanatgar Razieh. "FDM 3D printing of conductive polymer nanocomposites : A novel process for functional and smart textiles." Thesis, Lille 1, 2019. http://www.theses.fr/2019LIL1I052/document.
Full textThe aim of this study is to get the benefit of functionalities of fused deposition modeling (FDM) 3D printed conductive polymer nanocomposites (CPC) for the development of functional and smart textiles. 3D printing holds strong potential for the formation of a new class of multifunctional nanocomposites. Therefore, development and characterization of 3D printable functional polymers and nanocomposites are needed to apply 3D printing as a novel process for the deposition of functional materials on fabrics. This method will introduce more flexible, resource-efficient and cost-effective textile functionalization processes than conventional printing process like screen and inkjet printing. The goal is to develop an integrated or tailored production process for smart and functional textiles which avoid unnecessary use of water, energy, chemicals and minimize the waste to improve ecological footprint and productivity. The contribution of this thesis is the creation and characterization of 3D printable CPC filaments, deposition of polymers and nanocomposites on fabrics, and investigation of the performance of the 3D printed CPC layers in terms of functionality. Firstly, the 3D printable CPC filaments were created including multi-walled carbon nanotubes (MWNT) and high-structured carbon black (Ketjenblack) (KB) incorporated into a biobased polymer, polylactic acid (PLA), using a melt mixing process. The morphological, electrical, thermal and mechanical properties of the 3D printer filaments and 3D printed layers were investigated. Secondly, the performance of the 3D printed CPC layers was analyzed under applied tension and compression force. The response for the corresponding resistance change versus applied load was characterized to investigate the performance of the printed layers in terms of functionality. Lastly, the polymers and nanocomposites were deposited on fabrics using 3D printing and the adhesion of the deposited layers onto the fabrics were investigated. The results showed that PLA-based nanocomposites including MWNT and KB are 3D printable. The changes in morphological, electrical, thermal, and mechanical properties of nanocomposites before and after 3D printing give us a great understanding of the process optimization. Moreover, the results demonstrate PLA/MWNT and PLA/KB as a good piezoresistive feedstock for 3D printing with potential applications in wearable electronics, soft robotics, and prosthetics, where complex design, multi-directionality, and customizability are demanded. Finally, different variables of the 3D printing process showed a significant effect on adhesion force of deposited polymers and nanocomposites onto fabrics which has been presented by the best-fitted model for the specific polymer and fabric
Bouaziz, Rami. "Mise en œuvre et modélisation du comportement cyclique des polymères à mémoire de forme." Thesis, Lille 1, 2017. http://www.theses.fr/2017LIL10087.
Full textThe semi-crystalline thermoplastic shape memory polyurethane (TPU-SMPU) is a smart material which has the ability to return to its original shape after applying a large strain thermo-mechanical cycle when it is stimulated by heating. This smart material has the advantage of recovering even after more than 100% of strain during several thermo-mechanical cycles. To explore the performance of a smart component in a mechanical system, it is mandatory to master the prediction of its behavior through a numerical model. A constitutive model is, then, proposed to describe its thermo-mechanical behavior and to predict the shape memory response. Uniaxial tensile tests at small strain rates were performed at 60°C in order to analyze the hyper-elastic response for each cycle. Relaxation tests were carried out at the end of the previous tensile loading to highlight the viscoelastic response during the shape memory cycle. These experimental data were, then, used in a curve-fitting algorithm employing least-squares optimization approach in order to identify the parameters of the proposed model. At last, the shape memory effect was investigated by means of free and constrained recovery experiments. The proposed model was then implemented into Comsol Multiphysics. It predicts quite well the experimental results in all cycles. In order to assess its predictability, this model has, then, been applied to the design of 3D structures. Furthermore, the mechanical performance and the shape memory properties have been improved by the addition of halloysite nanotubes (HNTs) with different weight percentages of nanotubes contents using a melt extrusion process. This process induced a homogeneous distribution and a good dispersion of nanotubes throughout the TPU matrix. Mechanical tests in tension demonstrated that strength and modulus of the nanocomposites significantly increase with addition of halloysites without significant loss of ductility. Moreover, cyclic shape memory tests under large strain showed that shape memory properties, mainly the recovery speed, were also enhanced. Using a thermo-visco-hyperelastic model for shape memory polymers, we have investigated the effect of nanotubes addition on the mechanical parameters
Rauch, Sebastian. "Entwicklung von funktionellen Polymerbürsten mit modularen Eigenschaften." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-119752.
Full textMounkaila, Mahamadou. "Analyse impédancemétrique pour le suivi de cuisson ou de santé des structures composites carbone/époxyde : vers des matériaux intelligents pour le PHM des structures composites." Thesis, Toulouse 3, 2016. http://www.theses.fr/2016TOU30066.
Full textThe high-performance composite materials based on carbon fiber are increasingly used in critical security areas (aeronautics and civil engineering) for the high mechanical performances as regards to their low density. They offer many benefits such as mechanical strength, mass and consumption reduction. Thus, it is important to know their characteristics during curing process or their use. With the aim to optimize their use or to control their integrity, efforts are employed by using several techniques to monitor their curing cycle or the health of the structures during the conditioning stage and the service stage. Beyond the existing methods of unique measurement of the resistance or the capacitance of the material, we present herein a technique of electrical impedance analysis to extract some specific material properties (resistance, capacitance, Impedance and argument) in order to know its behavior. As the microstructure of the material contains a conductor part (carbon fiber) and an insulator part (resin), a three-dimensional (3D) model of the electrical conduction in the material was established by using a network of a resistance RP connected in parallel with a capacitance CP (impedance Z) to describe the anisotropy of the material. Then, the thin flexible electrodes (flex) are inserted inside the material and the specific impedance measurement bench is developed to perform a real-time measurement of RP and CP or Z and θ. Spectroscopic impedance analysis of the studied samples informs about the intrinsic properties of material and shows a sensitivity of these electrical properties according to the curing cycle. Then the sensitivity to some physical parameters (temperature, deformations, etc.) will be demonstrated in order to provide necessary elements to know or predict the health of the material for SHM (Structural Health Monitoring) and PHM (Prognostics and health management) purpose
Laure, William. "Dopamine : une molécule de choix pour l’immobilisation de polymères sur des substrats à base de titane : application à l’élaboration de surfaces "intelligentes" et à la fonctionnalisation de stents métalliques." Thesis, Lille 1, 2014. http://www.theses.fr/2014LIL10117/document.
Full textThe control of physico-chemical properties of titanium based materials is frequently needed with the aim of enhancing their capabilities, their biological activity or to design new « smart » materials. In this context, tethering of specific (macro)molecules seems to be a relevant method to develop stimuli responsive materials with predictable or commutable physico-chemical properties. In this work, we have elaborated numerous platforms for the functionalization of titanium surfaces by a combination of catechol adhesives properties and very efficient coupling reactions in order to graft functional polymers prepared by controlled radical polymerization. This approach allowed us to create reusable titanium surfaces with programmable wettability and materials capable of responding to external stimuli such as temperature or UV light. Finally, versatile polydopamine coating has been used to design a new generation of drug eluting stent which might be employed in cardiovascular surgery to struggle against in-stent restenosis
Chen, Xianlong. "Development of a low-cost in-situ material characterization method and experimental studies of smart composite structures." Thesis, Bourgogne Franche-Comté, 2019. http://www.theses.fr/2019UBFCA002/document.
Full textThe composite structures embedding piezoelectric implants are developed due to their abilities of modifying mechanical properties according to the environment, of keeping their integrity, of interacting with human beings or with other structures.This study is focused on the preliminary design stages of smart composite structures, which represent only 5% of the total costs of a project, whereas 80% of the life cycle cost are set during the preliminary study phases. The top few problems during the preliminary design of smart composite structures are addressed in this work such as the determination of the material properties of the piezoelectric transducers and composite material used, the influence of transducers location, manufacturing process, temperature and damage on the behavior of the smart composite structures.Due to the manufacturing process developed at the Université de Technologie de Belfort-Montbéliard (UTBM), the most important element is a semi-finished product called “soft layer”. This special layer is used to embed the transducers system into the composite structures. The manufacturing process of “soft layer” as well as the smart composite structures are compiled in this report.In order to solve the problems described above, two characterization methods of composite material (Resonalyser method and Time-of-Flight method (T-o-F method)), are introduced and discussed. After experimental studies and comparing the results of these two methods, the T-o-F method is chosen as the main method for the following studies due to the fact that it is a low-cost and in-situ characterization method. Furthermore, a new method based on the T-o-F method is developed to easily and quickly extract the elastic constants, in particular the Poisson’s ratio.Experimental sensitivity analyses applied to the smart composite structures are performed with respect to the problems describes above. First of all, the study of the influence of transducers location demonstrates that the "soft layer” cannot be neglected to model the behavior of the final product. In particular, the through-the-thickness position has an influence on the eigenfrequencies and the modal amplitudes. However, the "soft layer” does not increase the overall damping ratio of the final structures and the through-the-thickness position of the "soft layer” has no influence on the damping ratios. The Lamb wave propagation inside the composite material is not impacted by the "soft layer”. Secondly, the study of the impact of manufacturing process demonstrates that the impact of variability of parameters due to the manufacturing process is very important on the final response of the structure. Thirdly, the study of the influence of temperature on different kinds of smart composite structures proves that when temperature increases, the Young’s modulus of the smart composites decreases. But the attenuation of Young’s modulus according to temperature is different along different fiber directions, especially for the unidirectional composite structures. Furthermore, in this study, the sensitivity of Time-of-Flight method with respect to temperature is well proved by comparing the results with a traditional method like Dynamic-Mechanical Analysis (DMA). Last but not least, the study of the impact of the mechanical damage gives a quite good reference for the future investigations. Along this way, it is possible to use a Time-of-Flight method in Structural Health Monitoring. In addition, some smart composite structures manufactured by the research team are given and their potential applications are discussed
Tuloup, Corentin. "Process and structural health monitoring of Polymer-Matrix Composites (PMC) using embedded piezoelectric transducers." Thesis, Compiègne, 2020. https://bibliotheque.utc.fr/Default/doc/SYRACUSE/2020COMP2593.
Full textThis innovative work studies the interest of integrating piezoelectric transducers (ceramic and/or polymer-based) within Polymer- Matrix Composite materials (PMC) to perform real-time and in-situ monitoring of their manufacturing process (Process Monitoring PM) as well as their lifespan (Structural Health Monitoring SHM). To do this, the piezoelectric transducers were integrated into the heart of the fibrous stacks using an innovative methodology developed within the "Materials and Surfaces" research team at the Roberval laboratory. The Liquid Resin Infusion (LRI) manufacturing system used (PM campaign), as well as the resulting samples tested mechanically (SHM campaign), were multi-instrumented using several Non-Destructive Testing devices (NDT: Acoustic Emission (AE), Infrared Thermography (IRT), Digital Image Correlation (DIC), etc.) in order to establish multi-physical couplings between the signals of external NDT techniques and the internal signature (electrical capacitance) coming from the transducers integrated into the heart of the material. In PM, the piezoceramic (PZT) transducers were found to be sensitive to the various key steps of the LRI process (flow front passing, impregnation, end of injection, chemo-physical transitions during curing and associated consolidation rates) achieved at different hardener rates, and able to detect manufacturing defects. These results showed great potential, worthy of future use on an industrial scale. In SHM, after verification of the non-intrusiveness of the ceramic and polymer-based transducers integrated into the heart of the mechanical test specimens, the polymer transducers allowed a real-time evaluation of the triaxial strain state and the rigidity loss experienced by the host PMC during its mechanical loading. However, despite a Non-Working Threshold (NWT) linked to the brittleness of their constitutive material, the piezoceramic transducers have shown a high sensitivity to the detection and monitoring of damage in real-time when they are positioned intelligently with respect to the mechanical stress. These thesis works ended with a first attempt aimed at transposing the knowledge acquired on PM and SHM of in-situ piezoelectric transducers from a 2D “laboratory” scale to a 3D structural one closer to industrial realities. The multi-instrumented manufacturing of an “Omega” stiffener PMC structure integrating 14 piezoelectric transducers (PZT and P(VDF-TrFE) copolymer) and reinforced through-the-thickness by a carbon tuft thread allowed confirming the previously evidenced PM abilities of the PZT, and showed a difference between how the electrical capacitance signals of PZT and copolymers react to the whole manufacturing process
Alhajj, Assaf Salim. "Innovative nanostructured textiles for thermal comfort." Thesis, Lille 1, 2020. http://www.theses.fr/2020LIL1I012.
Full textFor the past ten years, photonic nanostructures have represented a paradigm for the control of thermal radiations, offering a panel of exciting properties for energy applications. Because of their abilities to control and manage electromagnetic waves at the Mid-Infrared (Mid-IR) wavelength scale, photonic nanostructures demonstrate their ability to manage thermal radiations properties in a way drastically different from conventional thermal emitters. The fundamental advances in controlling thermal radiation led to different applications in the energy domain, as thermo photovoltaic devices or through the concept of daytime radiative cooling to passively decrease the temperature of terrestrial structures. Recently, another field of application has appeared in the thermal radiation control, with the introduction of photonic nanostructures in textiles for personal thermoregulation. The goal of the thesis is to study different passive photonic membranes that modulate the human body optical radiations in the Mid-IR for personal thermoregulation. We have investigated the optical properties of different polymer membranes, considering the effect of their structuration. We showed that a photonic crystal membrane is able to modulate the transmission coefficient by 28% in benefit or deficit of both the absorption and reflection. We analyzed the thermal balance between the human body and the indoor environment through the photonic membrane, considering the radiation, convection and conduction mechanisms. We found that the temperature of the skin is almost 2°C higher when the human body is clothed with a structured membrane. The study was carried out on analytical calculations and numerical simulation with the help of the finite element method (FEM). The numerical study was supported by experiments in fabrication in the IEMN cleaning room and in characterization by infrared spectroscopy (FTIR) at the HEI engineering school
Morel, Aude. "Gestion des transferts thermiques et hydriques au sein d’une structure multicouche textile : développement d’une membrane pour application EPI." Thesis, Lille 1, 2014. http://www.theses.fr/2014LIL10124/document.
Full textThis study aims at developing a thermosensitive membrane allowing the water vapor to cross with a function of the temperature to enhance the comfort and the safety of firefighters. Membranes with different chemical structure were synthesized from segmented polyurethane. The influence of the polyol type and its length, and the hard segment content was studied. Two kinds of mechanisms were identified depending on the chemical structure as a bulk modification and a surface modification, that change moisture management properties. Afterwards, membranes were pressed on a textile for higher mechanical properties. The purpose of the final product is to be made inside the firefighter’s personal protective equipment, between the underwear and the jacket. The systems membrane-textile keep the properties of the membrane and present controlled water vapor permeability with the function of the temperature
Della, Schiava Nellie. "Development of electrostrictive P(VDF-TrFE-CTFE) terpolymer for medical applications." Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEI112.
Full textIn the 21st century, cardiovascular diseases became a major cause of mortality, the first in the entire world, the second in France after cancers. Indeed, cardiovascular risk factors have been increasing significantly over the past decades and this phenomenon is ongoing today. These factors cause atherosclerosis and lead to coronary acute syndrome, heart attacks, cerebrovascular accident, renal insufficiency but also to peripheral arterial disease (PAOD) and arterial aneurysms. First line treatment of atherosclerosis, regardless of arterial territory concerned, is medical treatment. But, if despite best medical treatment, symptoms are important for patients, interventional treatment may be considered. For aneurysms and for PAOD, vascular surgery is possible. Vascular surgery can be divided into two categories: conventional open repair (COR) and endovascular techniques (ET). During the last ten years, ET became the first line treatment for most arterial injuries. ET has become the first line treatment because it allows a considerable reduction in surgical morbi-mortality and a great reduction in health costs
Afzal, Muhammad Ali. "Development of a coaxial composite fiber." Thesis, Mulhouse, 2016. http://www.theses.fr/2016MULH0599/document.
Full textA coaxial composite fiber has been developed for the intended application in textile based sensors, actuators and eletric signal transmissions in wearable textile products. The work focuses on melt extrusion machine modification, characterization of polymers, characterization of developed filaments and optimization techniques for obtaining required results. Melt extrusion machine has been used having piston based mechanism. The process design and optimization was done using polyester polymer. The machine modification includes design of spinnert, piston end modification and introduction of separate feeding channel for core filament in the oven. A number of 10 spinnerets designs were developed according to industrial die design rules and optimized for their performance. The piston end designs developed were 3 in number. A stainless steel tube has been introduced into the oven for a separate secure passage of core filament. The polymer characterization was done by thermal, rheological and analytical techniques. The obtained results exhibited thermal attibutes of the polymer and showed reduction in degree of crystallanity in composite filament. The optimization of extrusion parameters including piston speed, winding speed ; and modifications in machine which includes design parameters of number of holes, tube position, tube internal diameter and spinneret exit diameter were done. It was observed that design parameters have significant effect on cross-sectional shape, eccentricity of core and morphology of filament. The characterization of composite filament has been carried out by physical, morphological, mechanical, tribology and bending techniques. The composite filaments developed were in range of 350-500 µm diameter. The filaments developed have elliptical, triangular, rectangular and circular shapes. The regular filaments showed higher tenacity and breaking strength than irregular shaped filaments. The frictional coefficient values were found higher for irregular shapes. Bending stiffness results obtained were not reliable for irregular cross-sectional shapes. The optimized parameters wers used to develop composite filament using ferroelectric polymer (PVDF-TrFE) having 70 :30 ratio copolymer. The developed filament was very regular in shape with good eccentricity of core. The developed Cu/PVDF-TrFE core/sheath filament can be used for development of sensors and actuators. The Cu/Polyester core/sheath filament can be used for electrical signal transmission lines in wearable electronic textiles and for development of electromagnetic shielding effectiveness fabrics
Aubry, Carole. "Développement et mise en oeuvre de structures textiles multifonctionnelles contenant des nanotubes de carbone : application aux capteurs chimiques pour la détection de solvants." Thesis, Lille 1, 2009. http://www.theses.fr/2009LIL10153/document.
Full textThis work is performed through the European project Inteltex. The aim is to develop new textile structures for the solvent detection. The use of CPC (Conductive Polymer Composite) composed of an insulating polymer matrix and conductive fillers, allows to detect the solvent presence by the swelling of the polymer that induces the conductive network deconnexion and the decrease of the electrical conductivity. The use of carbon nanotubes (CNT) as conductive fillers is a biggest advantage because only a low content is necessary to achieve the appropriate electrical conductivity for sensing (10-3 S/m). The different sensitive and spinnable matrices are polycarbonate (PC), polylactide (PLA) and polyethylene terephthalate (PET). The percolation threshold of CNT in 1.5 mm diameter monofilament, produced by extrusion, is determined between 1.5 and 2 wt.% of CNT. The elaboration of multifilament yarns by melt spinning process show a decrease of the conductivity with the drawing effect. In order to maintain the electrical properties, PLA fibers containing at least 4 % of CNT and having a minimum diameter of 80 µm have to be produced. In this way it is necessary to introduce a plasticizer to improve the composites spinnability. The electrical, thermal, mechanical, morphological properties and fluidity of filaments were studied depending on the processing conditions and their composition. Composite fibers, close the percolation threshold, show sensitivity to humidity, ethanol and toluene
Tamara, Erceg. "Strukturiranje polimernih mreža na osnovu akrilamida i akrilne kiseline." Phd thesis, Univerzitet u Novom Sadu, Tehnološki fakultet Novi Sad, 2019. https://www.cris.uns.ac.rs/record.jsf?recordId=111003&source=NDLTD&language=en.
Full textIn this paper, hydrogels based on acrylamide and acrylic acid were synthesized using conventional and microwave synthetic methods via free-radical polymerization. The initial monomers ratio and amount of crosslinking agent were varied in order to investigate the effect of the composition of the reaction mixture on the properties of the obtained hydrogels. The conditions of synthesis in the microwave field as faster simpler and more economical method have been optimized. In order to establish a correlation between the mechanism of synthesis, structure and properties of the obtained hydrogels using the relevant methods of characterization, the absorption, rheological, thermal and structural properties of the hydrogels obtained by the two methods were compared. It has been found that the microwave synthesis is a faster and simpler method, which enables reduced consumption of time and energy and produces hydrogels competitive to those ones obtained by conventional heating in aqueous solution. The second part of the thesis includes the synthesis of hydrophilic polymer networks based on sodium carboxymethylcellulose (NaCMC) and carboxylic acids, whereby one series is synthesized by interpenetration of the network using the linear acrylamide and acrylic acid copolymers in order to increase the potential application of hydrogels for flocculation purposes. The results of measurements of swelling, structural, thermal and flocculation properites have shown mutual agreement. The obtained results have shown that among applied carboxylic acids, citric acid in the amount of 15% per mass of NaCMC, has given the hydrogels with the best properties. The Combination of this network with a copolymer of acrylamide and acrylic acid in a mass ratio of 10/90 has created a theoretical platform for the production of flocculant which could show high efficacy in purifying of water dominated by positively charged particles.
Fisher, Omar Zaire 1979. "Novel pH-responsive microgels and nanogels as intelligent polymer therapeutics." 2008. http://hdl.handle.net/2152/17850.
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Rungroungdouyboon, Bunyong. "An investigation of initial polymer sheet heating processes during intelligent thermoforming /." Diss., 2003. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3117175.
Full textShofner, Justin Patrick 1983. "Oral delivery of protein-transporter bioconjugates using intelligent complexation hydrogels." 2008. http://hdl.handle.net/2152/18125.
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Rodrigues, Beatriz Vilaranda. "Desenvolvimento e caracterização de complexos polímero-lipossoma (CPLs) para sistemas inteligentes de libertação controlada." Master's thesis, 2017. http://hdl.handle.net/10316/83224.
Full textThe aim of this work was the development and characterization of Polymer-Liposome Complexes (PLC) as intelligent systems for controlled release. For the PLC formulation, it was selected polymers with the ability to react to stimuli, particularly to the pH and temperature. Due to its amphiphilic properties, Pluronic® F68 (PLU) was chosen as polymer for PLC, but also, for polyacrylic acid (PAA) and poly(dimethylaminoethyl methacrylate) (PDMAEMA) anchor to liposomes. In this way, it was synthetized by ATRP the polymers PLU-PAA (PP) e PLU-PDMAEMA (PPD), to guarantee that the molecular weight and polydispersity were controlled. For the polymerizations, it was necessary to synthetize the initiator. The initiator was obtained by esterification of the PLU with 2-bromoisobutyryl bromide (2-BiB).To create the PLC, polymers were incorporated in soy lecithin liposomes in different polymer/phospholipid ratios (2,5 %, 5 %, e 10 %). Also Stearylamine (SA) and Cholesterol (CHO) were added to understand the impact of this compounds in the formulation. The PLC were characterized by their size, polydispersity, zeta potential and release profiles at 37 °C and pH 7, release at 42 °C and with different pH and encapsulation efficiency, after encapsulated with calcein.The results revealed that the PLC had an adequate size for their use in vivo, and that the smallest ones were constituted by LC and polymer. The PLC with 10 % of PP are the exception to this statement. It was demonstrated that the PLC with 10 % PLU, PP and PPD incorporated had the best calcein release profiles for pH 7 and 37 ºC. PLC with 10 % PPD had the lowest release values, compared to the ones with 2,5 % and 5 %, and lecithin liposomes. Release studies at a higher temperature (42 ºC) and with different pH, were only made to the PLC with 10 % of polymer incorporated, as these demonstrated the best results in the previous release study. Even though the PLC proven to be biocompatible, it was verified that they had a low encapsulation efficiency.So, the PLC formulated have good characteristics for their utilization in vivo, like their biocompatibility, reduced size and temperature sensitiveness. The reduced size favors the PLC stability in vivo, since smaller vesicles are less attacked from the immune system than bigger ones. In this way, they have a bigger longevity in vivo. The sensitiveness to temperature allows the release of the PLC encapsulated content with the desired conditions. Also the biocompatibility indicates that these systems do not have a toxic effect in healthy cells. In addition, it was showed their potential by the chosen polymers and the way they were synthetized.
Neste trabalho, pretendeu-se desenvolver e caracterizar Complexos Polímero-Lipossoma (CPL) para sistemas inteligentes de libertação controlada. Para tal, foram utilizados polímeros com a capacidade de reagirem ao pH e à temperatura, para a formação dos CPL. O Pluronic® F68 (PLU) foi um dos polímeros utilizados devido às suas propriedades anfifílicas. Estas propriedades permitem que este polímero seja o elemento ideal para a ancoragem dos polímeros Poli(ácido acrílico) (PAA) e Poli 2-(N,N-Dimetilamina) etilmetacrilato] PDMAEMA aos lipossomas. Assim, os polímeros PLU-PAA (PP) e PLU-PDMAEMA (PPD) foram sintetizados através de polimerizações ATRP, para garantir o controlo do peso molecular e da polidispersividade. Para as polimerizações, foi necessária a síntese do iniciador PLU-Br, a partir da esterificação do PLU com o Brometo de 2-Bromoisobutiril (2-BiB).Os polímeros foram incorporados em lipossomas de lecitina de soja (LC) com diferentes razões polímero/fosfolípidos (2,5 %, 5 %, e 10 %), para a criação dos CPL. Para além dos polímeros, também foi adicionada estearilamina (SA) e colesterol (CHO), para perceber o impacto destes compostos nas características dos CPL. Os CPL obtidos foram caracterizados a nível do tamanho, da polidispersividade, do potencial zeta e dos perfis de libertação a 37 °C e pH 7, da libertação a 42 °C e com diferentes pH e da eficiência de encapsulação, após o encapsulamento com calceína.Os resultados revelaram que os CPL possuíam um tamanho adequado para a sua utilização in vivo. Os CPL formulados por apenas LC e com os polímeros PLU, PP e PPD apresentam os tamanhos mais pequenos, à exceção dos CPL com 10% de PP. Os resultados também demonstraram que os CPL com 10 % de polímero incorporado tinham uma taxa de libertação de calceína inferior a 37 °C e a pH 7, em relação aos CPL de 2,5 % e 5 % e aos lipossomas de LC. Os CPL com 10 % de PPD são os que apresentam os valores mais baixos de libertação nestas condições. O estudo da libertação a diferentes pH e com uma temperatura mais alta (42 °C), da eficiência de encapsulação e da viabilidade celular foi efetuado com os CPL de 10 % de PLU, PP e PPD, uma vez que foram estes que mostraram os melhores resultados a pH 7 e 37 °C. Apesar dos testes demonstrarem a biocompatibilidade dos CPL, verifica-se que a eficiência de encapsulação é baixa.Portanto, os CPL formulados apresentam características ideais para a sua utilização in vivo, como a sensibilidade à temperatura, a biocompatibilidade e tamanho reduzido. O tamanho reduzido favorece a estabilidade dos CPL in vivo, uma vez que quanto menor for o tamanho destas vesículas, menor o ataque do sistema imunitário e maior será a sua longevidade. A sensibilidade à temperatura permite que o conteúdo encapsulado nos CPL seja libertado nas condições alvo desejadas. A biocompatibilidade indica que estes sistemas não apresentam efeitos tóxicos para as células saudáveis. Assim, o seu potencial reside não só nestas características, mas também pelos polímeros utilizados e pela forma como foram sintetizados.
Owens, Donald E. 1979. "Thermally-responsive interpenetrating polymer network nanoparticles as intelligent therapeutic systems." Thesis, 2006. http://hdl.handle.net/2152/2843.
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