<p>Najče&scaron;ća komplikacija nakon ugradnje silikonskih implantata za dojku je kontraktura fibrozne kapsule (KK), koja se normalno stvara oko implantata u sklopu reakcije oko stranog tela. Najozbiljnija komplikacija nakon ugradnje silikonskih implantata za dojku je anaplastični krupnoćelijski limfom koji se javlja isključivo kod pacijentkinja koje imaju ugraĎene implantate (eng. Breast-implant associated anaplastic large cell lymphoma &ndash; BIA ALCL). Uzrok nastanka ovih komplikacija ostaje nepoznat. Ustanovljeno je da se KK manje javlja kod implantata koji imaju makroteksturisanu povr&scaron;inu i kod onih koji su presvučeni poliuretanskom penom. S druge strane, BIA-ALCL se če&scaron;će dijagnostikuje kod pacijentkinja kojima su ugraĎeni upravo makroteksturisani implantati. Subklinička infekcija koja predstavlja odgovor organizma na postojanje biofilma na ugraĎenim implantatima, predstavlja jedan od najznačajnijih etiolo&scaron;kih faktora za nastanak KK i BIA-ALCL. Biofilm je konglomerat mirkoorganizama uronjenih u matriks koji ih &scaron;titi od dejstva antibiotika i antiseptika. Kako je nemoguće delovati medikamentozno na eradikaciju biofilma, brojni autori daju razne preporuke u cilju izbegavanja kontaminacije implantata tokom operativnog zahvata, a time i formiranja biofilma. Pored brojnih mera, savetuje se i ispiranje džepa u koji će se plasirati proteza kao i same proteze, nekim od antiseptičkih ili antibiotskih rastvora. Do sada ne postoje prihvaćene jasne preporuke o načinu ispiranja različitih implantata, objavljena su samo lična iskustva raznih autora. Ciljevi ovog istraživanja su bili da se ustanovi mogućnost formiranja biofilma četiri različite bakterije (Staphylococcus epidermidis, Staphylococcus aureus, Pseudomonas aeruginosa i Ralstonia pickettii) na tri različito teksturisana silikonska implantata za dojku (sa porama veličine 70-150 &mu;m, 50&ndash;900 &mu;m i 13 &mu;m) u in vitro uslovima; da se ispita da li ispiranje antisepticima (oktenidindihidrohloridom i povidon jodom), ili antibiotikom (cefuroksimom) ili istovremeno me&scaron;avinom povidon joda i antibiotika pre bakterijske kontaminacije sa četiri različite bakterije ima uticaja na formiranje biofilma na tri različito teksturisana implantata za dojke u in vitro uslovima; i da se ispita efekat antiseptika u odnosu na efekat antibiotika na formiranje bakterijskog biofilma na tri različito teksturisana silikonska implantata za dojku. Istraživanje je koncipirano kao prospektivna studija u vidu eksperimenta koji je izveden u Laboratoriji za mikrobiologiju, Instituta za javno zdravlje Vojvodine u Novom Sadu. Za izvoĎenje eksperimenta kori&scaron;ćeni su uzorci tri vrste silikonskih implantata za dojku sa različito teksturisanom povr&scaron;inom, odnosno porama različite veličine: 70-150 &mu;m, 50&ndash;900 &mu;m, i 13 &mu;m. Od svakog od navedenih implantata su pravljeni uzorci, sečenjem kapsula implantata na komadiće veličine 1x1 cm. Ukupno je bilo 1440 uzoraka. Na osnovu teksture uzorci su podeljeni u tri grupe: Grupa 1 (pore veličine 70-150 &mu;m), Grupa 2 (pore veličine 50&ndash;900 &mu;m) i Grupa 3 (pore veličine 13 &mu;m). Svaka od ovih grupa je dalje podeljena u jednu kontrolnu grupu i po četiri ispitivane grupe. Nakon sterilizacije uzoraka svaka kontrolna grupa je kontaminirana sa po 100&mu;l bakterijskog bujona Staphylococcus epidermidis (n=30), Staphylococcus aureus (n=30), Pseudomonas aeruginosa (n=30) i Ralstonia pickettii (n=30). Ispitivane grupe se bile podeljene prema načinima ispiranja na one u kojima su uzorci prvo ispirani: oktenidin &ndash; dihidrohloridom ili povidon jodom ili cefuroksimom ili kombinacijom povidon joda i dva antibiotika, pa potom kontaminirani sa po 100&mu;l bakterijskog bujona Staphylococcus epidermidis (n=30), Staphylococcus aureus (n=30), Pseudomonas aeruginosa (n=30) i Ralstonia pickettii (n=30). Po zavr&scaron;enoj kontaminaciji, uzorci su se inkubirali na temperaturi od 37&deg;C u trajanju od 96h, čime su stvoreni uslovi za formiranje biofilma. Nakon inkubacije, svaki pojedinačni uzorak je uronjen u sterilan tripton soja bujon, izlagan soničnoj energiji u trajanju od 1minuta i zatim vorteksiran 1 minut, čime je omogućeno odvajanje nastalog biofilma od implantata. Za ispitivanje sposobnosti formiranja biofilma kori&scaron;ćena je modifikovana tehnika sa mikrotitar pločom po Stepanoviću. Rezultati su pokazali da sve četiri ispitivane bakterije S. epidermidis, S. aureus, P. aeruginosa i Ralstonia pickettii statistički značajno vi&scaron;e stvaraju biofilm na implantatima sa porama veličine 50&ndash;900 &mu;m u odnosu na pore 70-150 &mu;m i u odnosu na pore veličine 13 &mu;m. Biofilm se statistički značajno vi&scaron;e stvara na porama veličine 70-150 &mu;m u odnosu na pore 13 &mu;m. Jedini izuzetak je Pseudomonas aeruginosa kod kojeg ne postoji statistični značajna razlika u produkciji biofilma na teksturisanim implantatima sa porama veličine 70-150 &mu;m u odnosu na one sa porama 13 &mu;m. TakoĎe, sve četiri ispitivane bakterije statistički značajano manje stvaraju biofilm nakon ispiranja povidon jodom, oktenidin-dihidrohloridom ili rastvorom antibiotika u sve tri grupe implantata, u odnosu na povr&scaron;ine koje nisu ispirane. Izuzetak je S. epidermidis u Grupi 3 kod kojeg nije utvrĎeno statistički značajno manje formiranje biofilma nakon ispiranja oktenidin dihidrohloridom u odnosu na neispiranje. Cefuroksim je bio efikasniji u sprečavanju formiranja biofilma sve četiri ispitivane bakterije u odnosu na neispiranje u Grupi 1, kao i za S. epidermidis i Ralstoniu Pickettii u Grupi 2. Cefuroksim se nije pokazao statistički značajno efikasnim u sprečavanju formiranja biofilma S. aureus i P. aeruginosa u Grupi 2, kao ni kod jedne bakterije u Grupi 3. Dalje je dokazano da su antiseptici (oktenidin-dihirohlorid i povidon jod) kao i me&scaron;avina povidon joda i dva antibiotika (cefuroksim i gentamicin), statistički značajno efikasnji od ispiranja samo antibiotikomcefuroksimom u smanjenju formiranja biofilma sve četiri ispitivane bakterije kod sva tri ispitivana, različito teksturisana silikonska implantata. Rezultati su pokazali da je ispiranje povidon jodom statistički značajno efikasnije u prevenciji stvaranja biofilma kod skoro svih ispitivanih bakterija od ispiranja oktenidin- dihidrohloridom u sve tri grupe implantata. Statistički značajna razlika nije utvrĎena u prevenciji stvaranja biofilma Staphylococcus aureusa kod sve tri grupe implantata prilikom ispiranja povidon jodom u odnosu na oktenidin- dihidrohlorid, kao i kod Ralsotnia pickettii u Grupi 2. Na osnovu rezultata ove studije, preporuka je da se koriste mikroteksturisani implantati kao i da se oni, pre ugradnje isperu povidon jodom ili me&scaron;avinom povidon jod i dva antibiotika (cefuroksim i gentamicin), u cilju prevencije stvaranja biofilma, a time i postoperativnih komplikacija koje mogu nastati nakon ugradnje implantata.</p> / <p>The most common complication after breast implant surgery is contracture of capsule, which is normally formed around implants as part of foreign body reaction. The most sincere complication after this kind of surgery is breast implant associated anaplastic large cell lymphoma (BIA-ALCL). The cause of these complications is still unknown. It is evident that capsular contracture (CC) is seen less frequently in patients with macro-textured implants and in those with implants covered with polyurethane foam. On the other hand, BIA-ALCL is diagnosed more frequently in patients with those, macro-textured implants. Subclinical infection, defined as an response of organism on presence of biofilm on the implant, is considered to be one of the most important etiologic factors for CC and BIA-ALCL. Biofilm is a conglomerate of microorganisms immersed into matrix, which protects them from influence of antibiotics and antiseptics. As it is impossible to eradicate biofilms with medicaments, many authors suggest different steps in order to avoid contamination of the implant during the operation and therefore, prevent the formation of biofilm. Among many tips, it is recommended to irrigate the pocket for breast implant and the implant itself, with some antiseptic or antibiotic solution. Up till now, there is no agreed consensus on the type of irrigation for different implants. Only personal experiences of a few authors have been published. Aims of this research were: to establish the possibility of biofilm formation of four different bacteria (Staphylococcus epidermidis, Staphylococcus aureus, Pseudomonas aeruginosa and Ralstonia pickettii) on three differently textured breast implants (with pore diameter of 70-150 &mu;m, 50&ndash;900 &mu;m and 13 &mu;m) in vitro; to examine whether the irrigation of implant with antiseptics (povidone iodine and octenidine dihydrochloride), antibiotics (cefuroxime) or mixture of povidone iodine and two antibiotics, before the contamination with bacteria, has an influence on the incidence on biofilm formation on three differently textured implants; and to examine the effect of antiseptics in contrast to the effect of antibiotics on biofilm formation on three differently textured breast implants. The study was conducted as a prospective research that took place at the Laboratory for microbiology, at the Institute of public health of Vojvodina in Novi Sad. For the experiment, three types of silicone breast implants were used with different pore sizes: 70-150 &mu;m, 50&ndash;900 &mu;m and 13 &mu;m. Samples were made by cutting each of these types of implants into pieces sized 1x1cm. There were 1440 samples in total. According to texture, samples were divided it three groups: Group 1 (pore size 70-150 &mu;m), Group 2 (pore size 50&ndash;900 &mu;m) and Group 3 (pore size 13 &mu;m). Furthermore, each of these groups was divided in one control and four test groups. After sterilisation of samples, every control group was contaminated with 100&mu;l of bacterial broth of Staphylococcus epidermidis (n=30), Staphylococcus aureus (n=30), Pseudomonas aeruginosa (n=30) and Ralstonia pickettii (n=30). Tested groups were divided according to type of irrigation into those where samples were firstly irrigated with either: octenidine dihydrochloride of povidone iodine or cefuroxime of mixture of povidone iodine with two antibiotics, and after the irrigation, contaminated with 100&mu;l bacterial broth of Staphylococcus epidermidis (n=30), Staphylococcus aureus (n=30), Pseudomonas aeruginosa (n=30) and Ralstonia pickettii (n=30). After contamination, samples were incubated on 37&deg;C for 96h, which created excellent conditions for biofilm formation. After incubation, each sample was dipped into sterile tripton soy broth, and then exposed to sonic energy for 1 minute and vortexed for 1 minute, which made biofilm separate from the implant. For testing the capability of biofilm formation, modified technique with microtitar plates described by Stepanović was used. Results show that all four examined bacteria S. epidermidis, S. aureus, P. aeruginosa and Ralstonia pickettii form more biofilm on implants with pore sizes 50&ndash;900 &mu;m compared to implants with pore size 70-150 &mu;m and those with 13 &mu;m. Statistical significance was found in biofilm formation on implants with pores 70-150 &mu;m compared to implants with pores 13 &mu;m. Furthermore, all four examined bacteria form statistically less biofilm after the irrigation with any of used solutions: povidone iodine, octenidine dihydrochloride, antibiotic solution of mixture of povidone iodine and two antibiotics, in all three groups of implants compared to surfaces that were not irrigated. The exception is S. epidermidis in Group 3, where no statistical significance was found on biofilm formation after the irrigation with octenidine dihydrochloride compared to non-irrigation. Cefuroxime was more efficient in biofilm prevention for all four tested bacteria compared to non-irrigation in Group 1 and for S. epidermidis and Ralstonia pickettii in Group 2. There was no statistical significance found in prevention of S. aureus i P. aeruginosa biofilms when irrigating with cefuroxime in Group 2, as well as for all tested bacteria in Group 3. Furthermore, it was verified that antiseptics (octenidin dihydrochloride and povidone iodine) and mixture of povidone iodine and two antibiotics (cefuroxime and gentamycin), were statistically more efficient in biofilm prevention of all four examined bacteria in all groups of implants, compared to irrigation with antibiotic-cefuroxime alone. Results show that irrigation with povidone iodine is statistically more efficient in biofilm prevention of almost all examined bacteria compared to irrigation with octenidine dihydrochloride in all groups of implants. There was not found any statistical significance in prevention of Staphylococcus aureus biofilm when irrigating with povidone iodine compared to octenidine dihydrochloride in all groups of implants, and also in biofilm prevention of Ralsotnia pickettii in Group 2. According to results of this research, it is recommended to use micro-textured implants and to irrigate them with povidone iodine or mixture of povidone iodine and two antibiotics (cefuroxime and gentamycin) prior the implementation, in order to prevent biofilm formation which is most probable cause of postoperative complications after implant surgery.</p>

Les EPDM (Ethylène Propylène Diène Monomère) sont employés comme isolants des câbles électriques des centrales nucléaires. En raison de l’environnement radioactif, ils se dégradent plus rapidement qu’en environnement classique. La détermination de leur durée de vie est donc un enjeu industriel important. Pour y parvenir, ce travail a d’abord consisté à déterminer l’influence de la composition des EPDM sur leurs cinétiques de dégradation. Ainsi, deux EPDM de composition chimique différente ont été irradiés sous rayonnement en présence d’oxygène. Les suivis de la fraction soluble et de la densité de chaines actives en fonction de la dose, ont permis de mettre en évidence une dégradation par réticulation et coupures de chaines. A partir de modèles statistiques, les cinétiques de ces deux processus ont pu être estimées : la réticulation dépend de la proportion en ENB résiduels tandis que les coupures de chaines sont indépendantes de la composition chimique et du degré de réticulation initial. De plus, au - delà d’une certaine dose, les nœuds de réticulation semblent progressivement détruits. Nous nous sommes ensuite intéressés aux conséquences de l’irradiation sur les propriétés mécaniques et ce, d’abord à 80°C, pour s’affranchir de la présence de cristallites. Si dans tous les cas, l’irradiation conduit à une décroissance de la contrainte à la rupture, nos matériaux montrent une déformation à rupture qui augmente avec la dose contrairement aux matériaux de Planès et al. Pour s’affranchir du rôle des hétérogénéités sur l’initiation de fissure, les propriétés mécaniques d’éprouvettes entaillées ont ensuite été étudiées. L’énergie de déchirement est corrélée à l’énergie de rupture des matériaux entaillés et peut être décrite par le modèle de Lake et Thomas, à condition de prendre en compte la longueur réelle entre nœuds de réticulation des matériaux irradiés. Aussi, les propriétés en rupture de tous les matériaux sont améliorées quand ils sont étudiés à 25°C et la présence de cristallites masque les conséquences de la dégradation ; cet effet est ici très marqué en raison d’une importante chimie - cristallisation. Des EPDM chargés ATH ont alors été étudiés. Nos résultats confirment une accélération de la dégradation par les ATH, dépendant de la surface spécifique des charges. La compréhension des propriétés en rupture des composites s’avère complexe car la rupture peut être entrainée par divers processus en compétition. L’évolution des propriétés mécaniques des composites testés à 25°C est, comme pour la matrice pure, dépendante de l’évolution de la cristallinité et des propriétés de la phase amorphe. Enfin, ce travail remet en cause la pertinence des critères de durée de vie actuellement utilisés dans l’industrie. Les énergies de rupture étant plus directement corrélées aux paramètres microstructuraux, ne faudrait-il pas plutôt considérer ce paramètre comme critère? / EPDM (EThylene Propylene Diene Monomer) are used as insulation for electrical cables in nuclear plants. Because of the radiative environment, the degradation of these cables is accelerated and a strong industrial challenge consists in the prediction of the cables lifetime. To address this crucial industrial concern, we first looked into the influence of the chemical composition of EPDM on their kinetics of degradation. To do so, two EPDM with different chemical compositions have been irradiated under radiations and in the presence of oxygen. The soluble fraction and the active chain density have been monitored as a function of the irradiation dose, and revealed the degradation by cross-linking and chain scissions. Furthermore, the kinetics of these mechanisms have been estimated based on statistical models: the cross-linking kinetics depends on the residual ENB content while the chain scission kinetics vary neither with the chemical composition nor the initial cross-linking degree. Moreover, beyond an irradiation dose, the cross-links are progressively broken. The mechanical performances were then studied at 80°C to prevent crystallinity. If the irradiation induces a decrease of the stress at break, the materials show an increase of the strain at break conversely to the EPDM systems studied by Planès et al. The mechanical properties of notched samples have then been employed in order prevent heterogeneities driven crack initiation. The tearing energy measured was correlated with the failure energy of notched samples andcan be described by the Lake and Thomas model with account for the real length between cross-links. The same study has then been performed at 25°C where the properties at break are seen to improve. Such improvements despite irradiation confirm that crystallites attenuate the degradation. This effect is more pronounced for the current set of materials because of a strong chemi-crystallisation. The addition of ATH fillers has been studied as well, showing an acceleration of the matrix degradation with the specific surface of the fillers. The understanding of the mechanical properties at break of filled materials seems complex because the failure can be obtained by various competing processes. Nevertheless, the matrix chemical nature can be mentioned as an important factor since the difference between the matrix mechanical properties and the matrix-filler interface properties will trigger the creation of macro-defects at the origin of failure. As for the neat matrix, the evolution of the composites mechanical properties tested at 25°C depends on the evolutions of both the crystallinity and the amorphous phase. More generally, this work questions the relevance of the actual lifetime criterion used in the industry. The energies at break are more directly correlated to the microstructural parameters and thus could correspond to a relevant criteria for predicting these systems lifetime.

This doctoral thesis concerns flanking transmission in light weight, wooden multi-storey buildings within the low frequency, primarily 20-120 Hz. The overall aim is to investigate how the finite element method can contribute in the design phase to evaluate different junctions regarding flanking transmission. Two field measurements of accelerations in light weight wooden buildings have been evaluated. In these, two sources; a stepping machine, and an electrodynamic shaker, were used. The shaker was shown to give more detailed information. However, since a light weight structure in field exhibit energy losses to surrounding building parts, reliable damping estimates were difficult to obtain. In addition, two laboratory measurements were made. These were evaluated using experimental modal analysis, giving the eigenmodes and the damping of the structures. The damping for these particular structures varies significantly with frequency, especially when an elastomer is used in the floor-wall junction. The overall damping is also higher when elastomers are used in the floor-wall junction in comparison to a screwed junction. By analysing the eigenmodes, using the modal assurance criterion, of the same structure with two types of junctions it was concluded that the modes become significantly different. Thereby the overall behavior differs. Several finite element models representing both the field and laboratory test setups have been made. The junctions between the building blocks in the models have been modeled using tie or springs and dashpots. Visual observation and the modal assurance criterion show that there is more rotational stiffness in the test structures than in the models. The findings in this doctoral thesis add understanding to how modern joints in wooden constructions can be represented by FE modelling. They will contribute in developing FE models that can be used to see the acoustic effects prior to building an entire house. However, further research is still needed. / Denna doktorsavhandling behandlar flanktransmission i flervåningshus med trästomme, inom det lågfrekventa området, främst 20-120 Hz. Det övergripande målet är att undersöka hur finita elementmetoden kan bidra i konstruktionsfasen för att utvärdera olika knutpunkters inverkan på flanktransmissionen. Två fältmätningar av accelerationer i trähus har utvärderats. I dessa har två olika lastkällor använts, i den första en stegljudsapparat och i den andra en elektrodynamisk vibrator (shaker). Det visades att shakern kan ge mer detaljerad information, men eftersom vibrationerna även sprider sig till omgivande byggnadsdelar vid fältmätningarna var det svårt att estimera tillförlitliga dämpningsdata även då shaker användes. Fältmätningarna följdes av två mätningar i laborationsmiljö. Dessa två experiment utvärderades med experimentell modalanalys, vilket ger egenmoder och dämpning hos strukturerna. Dämpningen för dessa trähuskonstruktioner varierar kraftigt med frekvens. Extra stora variationer registreras då en elastomer användes i knutpunkten mellan golv och vägg. Den totala dämpningen är generellt högre när elastomerer används i knutpunkten mellan golv och vägg i jämförelse med då knutpunkten är skruvad. Genom att analysera egenmoder och deras korrelationer (MAC), för samma trästruktur men med olika typer av knutpunkter, drogs slutsatsen att knutpunkten drastiskt förändrar strukturens dynamiska beteende. Flera finita elementmodeller av både fält- och laboratorieuppställningar har gjorts. I dessa har knutpunkterna mellan byggnadsdelar modellerats helt styvt eller med hjälp av fjädrar och dämpare. Visuella observationer av egenmoder och korrelationen dem emellan visar att det finns mer rotationsstyvhet i försöken än i finita elementmodellerna. Resultaten i denna doktorsavhandling har gett förståelse för hur knutpunkter i träkonstruktioner beter sig och kan simuleras med finit elementmodellering. Vidare kan resultaten bidra till utvecklingen av FE-modeller som kan användas för att kunna se de akustiska effekterna redan under konstruktionsstadiet. Dock behövs ytterligare forskning inom området.

Part 1: Theoretic background information - Review of Hooke’s law for linear elastic materials - The strain energy density of linear elastic materials - Hyperelastic material - Material laws for hyperelastic materials - About selecting the material model and performing tests - Implementation of hyperelastic material laws in Mechanica - Defining hyperelastic material parameters in Mechanica - Test set-ups and specimen shapes of the supported material tests - The uniaxial compression test - Stress and strain definitions in the Mechanica LDA analysis Part 2: Application examples - A test specimen subjected to uniaxial loading - A volumetric compression test - A planar test - Influence of the material law Appendix - PTC Simulation Services Introduction - Dictionary Technical English-German / Teil 1: Theoretische Hintergrundinformation - Das Hookesche Gesetz für linear-elastische Werkstoffe - Die Dehnungsenergiedichte für linear-elastische Materialien - Hyperelastisches Material - Materialgesetze für Hyperelastizität - Auswählen des Materialgesetzes und Testdurchführung - Implementierung der hyperelastischen Materialgesetze in Mechanica - Definieren der hyperelastischen Materialparameter in Mechanica - Testaufbauten und Prüfkörper der unterstützten Materialtests - Der einachsige Druckversuch - Spannungs- und Dehnungsdefinition in der Mechanica-Analyse mit großen Verformungen Teil 2: Anwendungsbeispiele - Ein einachsig beanspruchter Prüfkörper - Ein volumetrischer Drucktest - Ein planarer Test - Einfluss des Materialgesetzes Anhang: - Kurzvorstellung der PTC Simulationsdienstleistungen - Wörterbuch technisches Englisch-Deutsch

Part 1: Theoretic background information - Review of Hooke’s law for linear elastic materials - The strain energy density of linear elastic materials - Hyperelastic material - Material laws for hyperelastic materials - About selecting the material model and performing tests - Implementation of hyperelastic material laws in Mechanica - Defining hyperelastic material parameters in Mechanica - Test set-ups and specimen shapes of the supported material tests - The uniaxial compression test - Stress and strain definitions in the Mechanica LDA analysis Part 2: Application examples - A test specimen subjected to uniaxial loading - A volumetric compression test - A planar test - Influence of the material law Appendix - PTC Simulation Services Introduction - Dictionary Technical English-German / Teil 1: Theoretische Hintergrundinformation - Das Hookesche Gesetz für linear-elastische Werkstoffe - Die Dehnungsenergiedichte für linear-elastische Materialien - Hyperelastisches Material - Materialgesetze für Hyperelastizität - Auswählen des Materialgesetzes und Testdurchführung - Implementierung der hyperelastischen Materialgesetze in Mechanica - Definieren der hyperelastischen Materialparameter in Mechanica - Testaufbauten und Prüfkörper der unterstützten Materialtests - Der einachsige Druckversuch - Spannungs- und Dehnungsdefinition in der Mechanica-Analyse mit großen Verformungen Teil 2: Anwendungsbeispiele - Ein einachsig beanspruchter Prüfkörper - Ein volumetrischer Drucktest - Ein planarer Test - Einfluss des Materialgesetzes Anhang: - Kurzvorstellung der PTC Simulationsdienstleistungen - Wörterbuch technisches Englisch-Deutsch

Beaucoup d'efforts dans le domaine des matériaux polymères sont déployés pour développer de nouveaux matériaux fonctionnels pour des applications spécifiques, souvent très sophistiquées, en employant des méthodes simplifiées de synthèse et de préparation. Cette thèse porte sur les polymères photosensibles – i.e. des matériaux fonctionnels qui répondent de diverses manières à la lumière – qui sont préparés à l'aide de la chimie supramoléculaire – i.e. une méthode de préparation qui repose sur l'auto-assemblage spontané de motifs moléculaires plus simples via des interactions non covalentes pour former le matériau final désiré. Deux types de matériaux photosensibles ont été ciblés, à savoir les élastomères thermoplastiques à base de copolymères à blocs (TPE) et les complexes d'homopolymères photosensibles. Les TPEs sont des matériaux bien connus, et même commercialisés, qui sont généralement composés d’un copolymère tribloc, avec un bloc central très flexible et des blocs terminaux rigides qui présentent une séparation de phase menant à des domaines durs isolés, composés des blocs terminaux rigides, dans une matrice molle formée du bloc central flexible, et ils ont l'avantage d'être recyclable. Pour la première fois, au meilleur de notre connaissance, nous avons préparé ces matériaux avec des propriétés photosensibles, basé sur la complexation supramoléculaire entre un copolymère tribloc simple parent et une petite molécule possédant une fonctionnalité photosensible via un groupe azobenzène. Plus précisément, il s’agit de la complexation ionique entre la forme quaternisée d'un copolymère à blocs, le poly(méthacrylate de diméthylaminoéthyle)-poly(acrylate de n-butyle)-poly(méthacrylate de diméthylaminoéthyle) (PDM-PnBA-PDM), synthétisé par polymérisation radicalaire par transfert d’atomes (ATRP), et l'orange de méthyle (MO), un composé azo disponible commercialement comportant un groupement SO3 -. Le PnBA possède une température de transition vitreuse en dessous de la température ambiante (-46 °C) et les blocs terminaux de PDM complexés avec le MO ont une température de transition vitreuse élevée (140-180 °C, en fonction de la masse molaire). Des tests simples d'élasticité montrent que les copolymères à blocs complexés avec des fractions massiques allant de 20 à 30% présentent un caractère élastomère. Des mesures d’AFM et de TEM (microscopie à force atomique et électronique à ii transmission) de films préparés à l’aide de la méthode de la tournette, montrent une corrélation entre le caractère élastomère et les morphologies où les blocs rigides forment une phase minoritaire dispersée (domaines sphériques ou cylindriques courts). Une phase dure continue (morphologie inversée) est observée pour une fraction massique en blocs rigides d'environ 37%, ce qui est beaucoup plus faible que celle observée pour les copolymères à blocs neutres, dû aux interactions ioniques. La réversibilité de la photoisomérisation a été démontrée pour ces matériaux, à la fois en solution et sous forme de film. La synthèse du copolymère à blocs PDM-PnBA-PDM a ensuite été optimisée en utilisant la technique d'échange d'halogène en ATRP, ainsi qu’en apportant d'autres modifications à la recette de polymérisation. Des produits monodisperses ont été obtenus à la fois pour la macroamorceur et le copolymère à blocs. À partir d'un seul copolymère à blocs parent, une série de copolymères à blocs partiellement/complètement quaternisés et complexés ont été préparés. Des tests préliminaires de traction sur les copolymères à blocs complexés avec le MO ont montré que leur élasticité est corrélée avec la fraction massique du bloc dur, qui peut être ajustée par le degré de quaternisation et de complexation. Finalement, une série de complexes d'homopolymères auto-assemblés à partir du PDM et de trois dérivés azobenzènes portant des groupes (OH, COOH et SO3) capables d'interactions directionnelles avec le groupement amino du PDM ont été préparés, où les dérivés azo sont associés avec le PDM, respectivement, via des interactions hydrogène, des liaisons ioniques combinées à une liaison hydrogène à travers un transfert de proton (acidebase), et des interactions purement ioniques. L'influence de la teneur en azo et du type de liaison sur la facilité d’inscription des réseaux de diffraction (SRG) a été étudiée. L’efficacité de diffraction des SRGs et la profondeur des réseaux inscrits à partir de films préparés à la méthode de la tournette montrent que la liaison ionique et une teneur élevée en azo conduit à une formation plus efficace des SRGs. / Much effort in the area of polymer materials involves the development of new functional materials for specific, often highly sophisticated, applications using simplified methods of synthesis and preparation. This thesis focuses on photo-responsive polymers – i.e. functional materials that respond in various ways to light – that are prepared with the aid of supramolecular chemistry – i.e. a preparation method that relies on the spontaneous selfassembly of simpler molecular building blocks via noncovalent interactions to form the final targeted material. Two types of photo-responsive materials were targeted, namely block copolymer thermoplastic elastomers (TPEs) and photo-responsive homopolymer complexes. TPEs are well-known, even commercial, materials that are typically based on triblock copolymers with a highly flexible middle block and rigid outer blocks that phase separate into isolated domains of the hard, outer block phase within a matrix of the soft block phase, and they have the advantage of being recyclable. For the first time, to our knowledge, we have prepared such materials with photo-responsive properties based on supramolecular complexation between a simpler parent triblock copolymer and a small molecule possessing the photo-responsive functionality via an azobenzene group. Specifically, this involved the ionic complexation of the quaternized form of a block copolymer, poly(dimethylaminoethyl methacrylate)-poly(n-butyl acrylate)-poly(dimethylaminoethyl methacrylate) (PDM-PnBAPDM), synthesized by atom transfer radical polymerization (ATRP), with methyl orange (MO), a commercially available SO3 --functionalized azo-containing compound. PnBA has a subambient glass transition (-46 °C) and the MO-complexed PDM outer blocks have a high glass transition (140-180 °C, depending on the molecular weight). Simple elasticity tests show that the complexed block copolymers with hard block weight fractions between about 20 and 30% have elastomeric character. AFM and TEM (atomic force and transmission electron microscopies) of spin-coated films show a correlation between the elastomeric character and morphologies where the hard block forms a dispersed minority phase (spherical and/or short cylindrical domains). A continuous hard phase (inverted morphology) is observed for a hard block content of around 37 wt %, which is much lower than found for neutral block iv copolymers due to ionic interactions. Reversible photoisomerization was demonstrated for these materials in both solution and in film form. The synthesis of the PDM-PnBA-PDM block copolymer was then optimized by using the halogen exchange technique in ATRP, along with other modifications to the polymerization recipe. Monodisperse products were obtained for both the macroiniaitor and the block copolymer. Based on a single parent block copolymer, a series of partially/fully quaternized and complexed block copolymers were prepared. Preliminary stretching tests on the MO-complexed block copolymers showed that their elasticity is correlated with the hard block content, which can be tuned by the degree of quaternization and complexation. Finally, a series of homopolymer complexes self-assembled from PDM and azobenzene derivatives bearing three different groups capable of directed interactions with the amino moiety of PDM (OH, COOH and SO3 -) were prepared, where the azo derivative associates with PDM via hydrogen-bonding interactions, by ionic bonding mixed with hydrogen bonding through proton-transfer (acid-base) interactions, and by purely ionic interactions via ion exchange procedures, respectively. The influence of the azo content and bonding type on surface relief grating (SRG) inscription was investigated. The SRG diffraction efficiencies and grating depths in spin-coated films show that ionic bonding and high azo content leads to more efficient SRG formation.

Part 1: Theoretic background information - Review of Hooke’s law for linear elastic materials - The strain energy density of linear elastic materials - Hyperelastic material - Material laws for hyperelastic materials - About selecting the material model and performing tests - Implementation of hyperelastic material laws in Mechanica - Defining hyperelastic material parameters in Mechanica - Test set-ups and specimen shapes of the supported material tests - The uniaxial compression test - Stress and strain definitions in the Mechanica LDA analysis Part 2: Application examples - A test specimen subjected to uniaxial loading - A volumetric compression test - A planar test - Influence of the material law Appendix - PTC Simulation Services Introduction - Dictionary Technical English-German / Teil 1: Theoretische Hintergrundinformation - Das Hookesche Gesetz für linear-elastische Werkstoffe - Die Dehnungsenergiedichte für linear-elastische Materialien - Hyperelastisches Material - Materialgesetze für Hyperelastizität - Auswählen des Materialgesetzes und Testdurchführung - Implementierung der hyperelastischen Materialgesetze in Mechanica - Definieren der hyperelastischen Materialparameter in Mechanica - Testaufbauten und Prüfkörper der unterstützten Materialtests - Der einachsige Druckversuch - Spannungs- und Dehnungsdefinition in der Mechanica-Analyse mit großen Verformungen Teil 2: Anwendungsbeispiele - Ein einachsig beanspruchter Prüfkörper - Ein volumetrischer Drucktest - Ein planarer Test - Einfluss des Materialgesetzes Anhang: - Kurzvorstellung der PTC Simulationsdienstleistungen - Wörterbuch technisches Englisch-Deutsch

Part 1: Theoretic background information - Review of Hooke’s law for linear elastic materials - The strain energy density of linear elastic materials - Hyperelastic material - Material laws for hyperelastic materials - About selecting the material model and performing tests - Implementation of hyperelastic material laws in Mechanica - Defining hyperelastic material parameters in Mechanica - Test set-ups and specimen shapes of the supported material tests - The uniaxial compression test - Stress and strain definitions in the Mechanica LDA analysis Part 2: Application examples - A test specimen subjected to uniaxial loading - A volumetric compression test - A planar test - Influence of the material law Appendix - PTC Simulation Services Introduction - Dictionary Technical English-German / Teil 1: Theoretische Hintergrundinformation - Das Hookesche Gesetz für linear-elastische Werkstoffe - Die Dehnungsenergiedichte für linear-elastische Materialien - Hyperelastisches Material - Materialgesetze für Hyperelastizität - Auswählen des Materialgesetzes und Testdurchführung - Implementierung der hyperelastischen Materialgesetze in Mechanica - Definieren der hyperelastischen Materialparameter in Mechanica - Testaufbauten und Prüfkörper der unterstützten Materialtests - Der einachsige Druckversuch - Spannungs- und Dehnungsdefinition in der Mechanica-Analyse mit großen Verformungen Teil 2: Anwendungsbeispiele - Ein einachsig beanspruchter Prüfkörper - Ein volumetrischer Drucktest - Ein planarer Test - Einfluss des Materialgesetzes Anhang: - Kurzvorstellung der PTC Simulationsdienstleistungen - Wörterbuch technisches Englisch-Deutsch