This study examined the concept of using a reactive blending process to develop new polymeric additive systems. The objective was to investigate the potential of using a reactive processing technique as a means to bond additives to functional polymers, to create “in situ” bonds between functional groups present on the polymers and those present on the additives. The work is reported in two parts; the first part studied the bonding of colorants to functional polyolefins and the second part investigated the bonding of UV stabilisers to functional polyolefins. The research was completed with the long term objective that the approach should offer alternative additives to conventional non-bonded systems for use in polypropylene. An ethylene ionomer was utilised for the bonding of dyes, this was chosen for its optical clarity and chemical functionality. Polyethylene methacrylic acid (EMAA) ionomers and methine dyes were blended in the melt phase using an internal mixer to produce bright intrinsically colored polymers. Fourier transform infrared spectroscopy (FTIR) in transmission mode was used to assess the bonding of the dye to the ionomer. Bonding resulted through electrostatic interactions between carboxylate groups on the ionomer and cations on the dye molecules. The reactive blending process also resulted in a change in the chromophoric structure of the dye. The bonded system was compared to a system whereby no bonding between the methine dye and polymer was expected. In the later system the methine dye was blended with polyethylene using an internal mixer. From FTIR results no interaction was observed between the dye and polyethylene in this system. This was supported by microscopic analysis that showed that the dye was present in the polyethylene as a dispersion. The second stage of research focussed on the UV stabilisation of polyolefins. A melt reaction was explored between polypropylene functionalised with maleic anhydride (PP-g-MA) and an alkoxyamine hindered amine light stabiliser (NOR-HALS) with hydroxyl functionality. The technology proposed is based upon the reaction between the carboxylic acid groups of maleated polypropylene and hydroxyl groups of a specific NOR-HALS (Tinuvin 152). The efficiency of the modification was assessed using FTIR to verify the esterification reaction between the NOR-HALS and the maleated polypropylene. This reaction resulted in the grafting of a pendant UV stabiliser to the polypropylene through an ester linkage. A twin-screw extruder (TSE) was used to complete this study. A larger quantity of material could be produced using a TSE compared to the colorant system where an internal mixer was used. Samples of the reactively blended materials were exposed to UV radiation for a maximum time period of three hundred hours to assess the resulting stability of the materials. Diffuse reflectance FTIR (DRIFT) spectroscopy and X-ray photoelectron spectroscopy (XPS) provided an effective means to study oxidative degradation. IR spectroscopic measurements were used to determine the effectiveness of HALS in inhibiting the photo-oxidation of maleic anhydride grafted polypropylene. The inhibition was quantified by measuring the formation of carbonyl groups, with and without HALS bonded to the polymer, at fixed exposure times of UV radiation. DRIFT and XPS analysis confirmed that stabilised samples oxidised less, as indicated by the lower carbonyl index values and O1s / C1s ratios. These findings were complemented by results from Charpy impact tests. The mechanical property results indicated that the longevity of the materials with UV stabilisers grafted to them exceeded the PPg- MA system where there was no stabiliser present. Visible spectrophotometry was used to assess the colour of the polymeric samples and change in colour following exposure to UV radiation. Samples with bonded HALS demonstrated greater colour stability than control samples. The microstructure of the polymer surfaces was viewed using scanning electron microscopy (SEM). The polymeric samples demonstrated resistance to crazing when the NOR-HALS were bonded to the polymer. For both the colorant and UV stabiliser areas of research, thermal properties of the materials were assessed using differential scanning calorimetry (DSC). It was found that increasing the additive concentration in the polymer resulted in an increase in the temperature of crystallisation (Tc). Melt flow index can indicate if any change in molar mass had occurred during processing. An increase in melt flow index values (MFI) was observed when additive loading increased which suggested that degradation of the polymer had occurred during processing. In summary, reactive processing showed considerable promise as a means to bond additives to a functional polypropylene.

Les polyolefins représentent plus de la moitié de la production mondiale de plastiques et 80% de ces polymères sont produits avec des catalyseurs hétérogènes de type Phillips, Ziegler-Natta et métallocènes. En effet, un bon fonctionnement des unités du fait d'un faible encrassement du réacteur ou des autres équipements de l'unité, une activité stable, une bonne morphologie particulaire des polymères et un une densité apparente élevée sont obtenus en utilisant des catalyseurs hétérogènes. D'un autre côté l'hétérogénéisation d'un catalyseur s'accompagne d'une diminution de l'activité et d'un élargissement de la distribution de masses molaires qui est parfois non désiré car cela peut influencer l'aptitude à la transformation et les propriétés mécaniques des polyoléfines. Plusieurs explications ont été avancées dans la littérature afin d'expliquer l'effet de l'immobilisation d'un catalyseur ce qui inclut la résistance diffusionnelle au transport du (des) (co)- monomère(s) vers le site actif et la modification du comportement du catalyseur conduisant à plusieurs espèces actives. Néanmoins l'ensemble de ces explications est en connexion avec les propriétés physiques du support (tailles des particules, surface spécifique, volume poreux, diamètre des pores…) car ce dernier peut en effet impacter la nature des espèces actives ainsi que leur dispersion et la diffusion des monomères. Les catalyseurs métallocène sont considérés comme mono-site et tout changement dans la nature du site actif au cours de son immobilisation et toute résistance au transfert de matière peuvent être détectés par un élargissement de la distribution des masses molaires. Le présent travail a pour objet d'étudier les effets des propriétés physiques des catalyseurs métallocènes supportés sur silice concernant la cinétique de polymérisation et les caractéristiques des polymères produits. Pour cela le traitement thermique de la silice a été fixé à 600°C afin de contrôler son état de surface tandis que la quantité de catalyseur supporté a été gardée autant que possible constante. De plus les protocoles de polymérisation en phases suspension et gaz ont été fixés après avoir évalué différentes conditions de polymérisation et différents composés alkylaluminium. Cette étude systématique a permis d'attribuer les différences observées en termes de cinétique de réaction des catalyseurs métallocènes à la différence des paramètres physiques des silices utilisées comme support et par conséquent à la résistance diffusionnelle au transport du (des) (co)-monomère(s) au(x) site(s) actif(s) durant la polymérisation / Polyolefins account for more than half of the world’s plastic production and about 80% of these polyolefins are commercially produced with heterogeneous olefin polymerization catalysts such as Phillips, Ziegler-Natta and metallocenes. Trouble-free plant operation due to low fouling of the reactor or other plant equipment, relatively stable catalytic activity, good polymer morphology and high polymer bulk densities can be achieved by employing heterogeneous olefin polymerization catalysts. On the other hand, heterogenization of the olefin polymerization catalysts lead to drastic reduction in their activities and broadening of the polymer molar mass distribution which is undesirable in some cases because it can influence the processability and mechanical properties of the polyolefin grade. Various explanations have been proposed in the open literature to explain these effects of catalyst immobilization which mainly include existence of diffusion resistance to (co)-monomer(s) transport at the active sites during polymerization and the change of the active site(s) behavior due to immobilization leading to multiple site types on the final supported catalyst. Nevertheless, both of these explanations have a connection with the physical properties (e.g., particle size, surface area, pore volume, pore diameter etc.) of the support because the support can impact the nature of the final active species formed on it, dispersion of the active species throughout the support particles and, last but not the least, the intraparticle diffusion of (co)-monomer(s) during polymerization. Metallocenes are considered as single-site catalysts and any changes in the nature of the active site(s) upon their immobilization on a support or during the course of polymerization due to mass transfer resistance can be detected from the broadening of polyolefin molar mass distribution. Therefore, the present work is an attempt to study the effects of physical properties of silica supported metallocenes on their ethylene polymerization kinetics as well as on the morphology of the produced polyethylene. For this purpose, the surface chemistry of the used commercial silica supports was fixed by dehyroxylating all of them at 600 °C, whereas, the final metal loadings of the supported catalysts were nearly kept constant by preparing them under identical conditions. Furthermore, slurry and gas phase polymerization protocols along with the used aluminum alkyl scavenger (which can also induce chemical effects on the catalytic behavior of supported metallocenes) were also fixed by testing different polymerization protocols and scavengers. Such systematic study has allowed us to attribute the observed differences in the reaction kinetics of the supported metallocenes, explicitly, to the differences in the physical parameters of the silica supports and, consequently, to the existence of diffusion resistance to (co) monomer(s) transport at the active site(s) during the course of polymerization

Plastics are highly useful economically because of their resistance to diverse types of environmental and chemical agents and their ability to be molded into many types of products. Globally, plastic production is greater than 20 million metric tons per year. However, their widespread use and often their disposable nature results in significant plastic accumulation in the environment. Plastics are made of hydrocarbons, materials that are biodegradable depending on their molecular structure and size. It is hypothesized that pre-treatment of plastic materials could enhance their bioavailability, facilitating their microbial biodegradation. In this dissertation, a process was developed to treat nylon 6,6 polymers by acid hydrolysis to produce a microbial growth medium. The chemical composition of the medium was determined by low pressure liquid chromatography-spectrophotometry and electrospray ionization mass spectrometry and found that the medium was a mixture of molecules with molecular weight > 800 m/z and with similar chemical characteristics to polyamines. There was steady growth of Pseudomonas putida KT2440 in the medium with concomitant substrate biodegradation. Notably, the yeast Yarowia lipolytica grew well in the medium when supplemented with yeast extract. A similar medium derived from nylon 6,6 containing nylon-derived particles supported the growth of Beijerinckia sp. and Streptomyces sp. BAS1. Confocal laser scanning microscopy and flame ionization gas chromatography were used to identify and quantify the production of polyhydroxybutyrate, a type of “bioplastic”. The aforementioned microorganisms were cultivated in a bench-scale bioreactor that was developed as part of this dissertation. The bioreactor had a novel impeller design resulting in enhanced mixing and rotation and also a modular format allowing for diverse configurations. The bioreactor was notable for its durability and low cost. A detailed description of its design is included in the appendices. In summary, plastic materials can potentially be processed into growth media for microorganisms and can be used for production of value-added products. The media described herein can be used in bioconversion processes using a bioreactor.

1 Ziel und Gegenstand der Untersuchungen Gegenstand der vorliegenden Arbeit war die Synthese und Charakterisierung von polaren Olefin-basierten Makromonomeren mit Hilfe von Metallocen-Katalysatoren. Polyolefine stellen eine Gruppe von Polymeren dar, die durch Additive oder chemische Veränderungen modifiziert, eine große Vielfalt von Einsatzmöglichkeiten auf der Basis einfach aufgebauter Monomere bieten. Sie stellen deshalb heutzutage die wichtigste Kunststoffgruppe dar. Ein Nachteil ist jedoch die unpolare Struktur dieser Polymere. Ziel dieser Arbeit war die Homopolymerisation polarer Olefine, um ein funktionalisiertes Polyolefin zu erzeugen, dass zudem auch als Makromonomer einsetzbar ist. Als Katalysatoren wurden im Wesentlichen die klassischen Metallocene auf Zr-Basis eingesetzt, aktiviert mit MAO. Die Makromonomere wurden im Anschluss an die Synthese umfassend charakterisiert. 2 Ergebnisse Zur Synthese wurde das bekannte 10-Undecen-1-ol (Undecenol) eingesetzt. Für eine erfolgreiche Homopolymerisation dieses Monomers ist eine effektive Abschirmung des Katalysators gegenüber der polaren Gruppe zur Minimierung der Deaktivierung des Katalysators zu gewährleisten. Für die Einführung von Schutzgruppen fand Triisobutylaluminium (TIBA) Verwendung. Auf diese Weise konnte erstmalig erfolgreich die Synthese von Polyundecenol mit Metallocen-Katalysatoren durchgeführt werden. Es zeigte sich, dass Undecenol als polares und zugleich sterisch anspruchsvolles Monomer mit der überwiegenden Anzahl der eingesetzten Metallocene schwierig zu polymerisieren ist, was im Vergleich zur Polymerisation von kurzkettigen 1 Olefinen, wie zum Beispiel Propen, anhand von geringen Molmassen (< 2000 g/mol) aber auch geringen Ausbeuten zum Ausdruck kommt. Die erzielten Molmassen der Polyundecenole sind jedoch für die Verwendung als Makromonomer vorteilhaft. Die höchsten Polymerausbeuten ermöglichte der Einsatz von ansa-Metallocenen. Mit dem Katalysator Et[Ind]2ZrCl2 konnten hierbei relative Ausbeuten im Bereich von 50 % bis 60 % bei gleichzeitig geeigneten Molmassen von < 10^4 g/mol erzielt werden. Bei der Verwendung von unverbrückten Metallocenen (bis-Cyclopentadienylkomplexe) sind die Ausbeuten und Molmassen im Vergleich zu den ansa-Metallocenen deutlich reduziert. Die synthetisierten Polyundecenole wurden hinsichtlich ihres Schmelz- und Kristallisationsverhaltens sowie der kristallinen Struktur untersucht und der Zusammenhang mit der Taktizität und der Molmasse der Polymere hergestellt. Die Ergebnisse der DSC und WAXS Untersuchungen lassen darauf schließen, dass für ataktische und isotaktische Polyundecenole eine Seitenkettenkristallisation als primäre Form der Kristallisation vorliegt. Aufgrund des hohen Gehalts von Hydroxylgruppen, die durch Wasserstoffbrückenbindungen wechselwirken, weist Polyundecenol hohe Schmelztemperaturen auf, im Vergleich mit dem unpolaren Poly(1-Undecen). So besitzt isotaktisches und auch ataktisches Polyundecenol bei vergleichbaren Molmassen eine um rund 80 K höhere Schmelztemperatur als Poly(1-Undecen). Die Wechselwirkung der Hydroxylgruppen wurde mittels FTIR-Spektroskopie nachgewiesen und liegt auch im geschmolzenen Zustand der Polymere vor. Anhand der Ergebnisse von WAXS-Untersuchungen konnte gezeigt werden, dass Polyundecenol in smektischen Schichten kristallisiert. Der Abstand zwischen den Hauptketten entspricht etwa zwei vollständig gestreckten Seitenketten des Polymers, welche orthogonal zur Hauptkette angeordnet sind. Diese Schicht-Anordnung wurde unabhängig von Molmasse und Taktizität der Polymere nachgewiesen und lässt die Schlussfolgerung zu, dass die Kristallisation isotaktischer Rückgrat-Ketten gegenüber der Seitenketten-Kristallisation unterdrückt ist. Es wurde jedoch beobachtet, dass die Taktizität einen Einfluss auf die Kristallisation hat. Polyundecenole mit isotaktischer Hauptkette weisen bei entsprechend langsamer Kristallisation eine Anordnung der Seitenketten in einer monoklinen Packung auf, was als Hinweis auf eine Kristallisation der Hauptkette interpretiert wird, auch wenn diese im Rahmen der Arbeit nicht eindeutig nachgewiesen werden konnte. Bei Polyundecenolen mit ataktischer Hauptkette ordnen sich die Seitenketten hingegen in einer hexagonalen Packung an, da die Hauptkette nicht in der Lage ist zu kristallisieren. Von besonderer Bedeutung für die Synthese der Polyundecenole waren einerseits die erzielbaren Polymerausbeuten, andererseits aber auch die Einführung geeigneter Endgruppen, welche ausschlaggebend sind für eine Nutzung als Makromonomer. Die Untersuchungen zum Polymerisationsverhalten verschiedener Metallocen-Katalysatoren zeigten, dass im Falle von ansa-Metallocenen sowie einem "CGC"-Komplex Polymere erhalten werden, die vor allem Endgruppen mit internen Doppelbindungen, doppelt- und dreifachsubstituiert, aufweisen. Solche Endgruppen sind jedoch für einen späteren Einsatz der Polymere als Makromonomer ungeeignet. Der Einsatz von unverbrückten Metallocen-Katalysatoren auf Basis der Biscyclopentadienyl-Struktur ermöglicht hingegen die Synthese von Polyundecenol mit einem hohen Anteil endständiger Vinyliden-Endgruppen zu synthetisieren. Die so erreichten Vinyliden-Endgruppenanteile bewegten sich nahezu unabhängig vom Katalysator im Bereich von etwa 85 % bis 90 %. Ein wesentliches Ergebnis der Arbeit stellt die Synthese von Polyundecenol mit Allyl-Endgruppen dar. Dieses wurde durch gezielte Kettenabbruchreaktionen mit Hilfe von Vinylchlorid erreicht. Bei Einsatz des Katalysator MBI konnten Anteile der favorisierten Allyl-Endgruppe von rund 90 % erreicht werden. Somit wurden auf diesem Wege erstmalig erfolgreich Polyundecenol-Makromonomere synthetisiert. Ein Einsatz dieser Polymere in der Copolymerisation mit Propen wurde aber durch geringe Ausbeuten verhindert. Jedoch konnte gezeigt werden, dass der Einsatz von Vinylchlorid die Synthese von Polyundecenol-Makromonomeren ermöglicht.

There has been an exponential increase of plastics being produced, used, and disposed of over the last 60 years. Most of plastic waste (76%) is consigned to landfills, 12% is incinerated, 3% ends up in the oceans while only 9% is recycled. If the current trend continues, more than 30 billion tons plastic waste will be generated on this planet and more plastic than fish will be in the oceans by 2050. Plastics take more than 100 years to degrade into plastic debris, microplastics, and toxic chemicals, which pose serious threats to the ecosystems, water and food supply, and eventually human health.<br>Polyolefins (Type 2 HDPE, Type 4 LDPE, and Type 5 PP), which are the majority (63%) of global plastic waste, are targeted in this study. Two methods, Hydrothermal Processing (HTP) and Sequential Selective Extraction and Adsorption (SSEA) were developed and tested. HDPE was converted into wax and oils using supercritical water under HTP at reaction temperature 400- 450 °C with reaction time 0.5- 3 hr. PP was converted into oils under supercritical water at 425 °C with reaction time 1- 3 hr. The oil products from HDPE and PP via HTP were composed of paraffins, olefins, cyclics, and aromatics with carbon numbers from C6 to C31. Reaction intermediates were analyzed using two-dimensional gas chromatography with a flame ionization detector (GC × GC-FID). The results were used to establish potential reaction pathways of HDPE and PP, respectively. PP was found to react faster than HDPE under the same HTP conditions while generating more olefins and cyclics than HDPE. Clean wax was obtained from PE waste via HTP. Its Fourier-Transform Infrared Spectroscopy (FT-IR) spectrum was almost identical to the one of commercial paraffin wax. Oils converted from PE waste via HTP was distilled into three fractions. The diesel-like fraction (170 °C≤ b.p. < 300 °C) has similar properties as No.1 ultra-low-sulfur diesel. It also can be used as a blendstock for No2. Ultra-low-sulfur diesel.<br>SSEA methods were developed to recover pristine polymers from polyolefin waste via extraction and adsorption. Mixed solvents with higher selectivity, reduced toxicity, and lower costs were found based on their Hansen Solubility Parameters. Extraction conditions were investigated using model polyolefins. Selective mixed solvents were found for the separation of LLDPE from LLDPE/PP blend. Pristine PE polymers were recovered from dark green PE waste pellets.<br>Preliminary analyses indicated HTP and SSEA have a higher energy efficiency and lower greenhouse gas (GHG) emissions than incineration, mechanical recycling, and pyrolysis. A combination of these two methods has the potential to convert 63% of the plastic waste into useful and profitable products. It also helps transform current linear path from crude oil to plastics to landfills, to a more sustainable circular path.<br>

L’entreprise Chomarat produit des feuilles en polyoléfine pour les revêtements intérieurs de voitures. Ces feuilles sont grainées afin de leur donner un aspect de surface particulier qui constitue un élément psychosensoriel important pour le consommateur. Les feuilles grainées doivent être thermoformées afin de pouvoir leur imprimer la forme de la structure rigide qui les supportera. L’étape de thermoformage se déroule à haute température et constitue de ce fait une étape critique du processus. En effet, lors de la déformation en température, l’étirement du matériau tend à déformer le grain de façon non homogène, voire à le faire disparaître. Pour obtenir des matériaux avec une bonne tenue du grain, les feuilles grainées sont partiellement réticulées. Ce travail de thèse vise à développer des formulations réticulables répondant à cette problématique. Deux voies de réticulation ont été envisagées : la réticulation par irradiation sous faisceau d’électrons et ou par insolation UV. Cette dernière méthode de réticulation est totalement novatrice dans ce domaine industriel. Les terpolymères éthylène-propylène-diène monomère (EPDM) présentent des caractéristiques favorisant la réticulation. L’effet de l’irradiation (EB ou UV) sur ces élastomères, ainsi que leurs mélanges avec du polypropylène (PP), a été étudiée. Les caractérisations ont principalement été menées par des mesures de rhéologie, des mesures de taux de gel et des calculs de densité de réticulation. Dans un premier temps, seule l’irradiation EB a été testée, sur des EPDM ainsi que sur d’autres types d’élastomères. Ensuite, les effets de l’irradiation UV ont été étudiés à travers la mise en place d’une étude modèle sur des oligomères de faibles masses choisis pour simuler le comportement des doubles liaisons des EPDM. La composition des différentes formulations étudiées comprenait donc un oligomère, un monomère multifonctionnel et un photoamorceur permettant la photoréticulation. Suite à cette étude, les meilleurs couples « photoamorceur / agent de réticulation » ont été transposés à des EPDM, d’abord en utilisant un EPDM de faible masse molaire puis un EPDM de haute masse molaire utilisé couramment dans les formulations au niveau industriel. Enfin, l’ajout du PP et en dernier lieu l’ajout de pigments et d’agents anti-UV ont été étudiés sur l’efficacité de la photoréticulation. / The Chomarat company manufactures polyolefin based sheets for automotive parts. These sheets are grained in order to give them a particular surface pattern which represents an important psycho-sensory aspect for consumers. The grained sheets must be thermoformed to give them the shape of the rigid structure on which they will be set in place. The thermoforming step is proceeded at high temperature and is therefore a critical step of this process. Indeed, while being deformed in temperature, the stretching of the material tends to distort the grained pattern in a non-homogeneous way and even to cancel it. In order to obtain materials that give an acceptable retention of the pattern after being thermoformed, the grained sheet must be partially crosslinked. This thesis work aims to develop crosslinkable formulations that are able to achieve this challenge. Two crosslinking methods have been considered: crosslinking using electron beam (EB) irradiation or UV irradiation. This last method is a pioneering crosslinking pathway in this industrial field. Terpolymers of ethylene-propylene-diene monomers (EPDM) have chemical structures that promote crosslinking. The effect of irradiation (EB or UV) on these elastomers, as well as on their blends with polypropylene (PP) have been studied. The characterisations have been mainly monitored using rheological measurements, gel contents measurements and crosslinking densities calculations. Firstly, only the effects of EB irradiation on EPDM and other types of elastomers have been investigated. Then, the effects of UV irradiation have been studied through a modelling study on low mass oligomers chosen to mimic the behaviour of EPDM double bonds. The different formulations studied were composed of an oligomer, a multifunctional monomer acting as a crosslinker and a photoinitiator allowing the crosslinking. Following this study, the best photoinitiator/crosslinking agent couples were transposed to EPDM, using firstly a low mass EPDM then a high mass one frequently used in formulations in industrial fields. At last, the effects on the photocrosslinking efficiency of adding first PP then pigments and anti-UV agents have been examined.

Deck and coworkers previously showed that Me3Si substituents adjacent to group 4 metallocene dichlorides (M = Ti, Zr, Hf) are converted to corresponding BrMe2Si groups using BBr3, and that these BrMe2Si substituents are highly reactive to nucleophilic reagents such as water. The high reactivity of the Si-Br bonds suggested that these substituents could react with hydroxyl groups on the surface of partially dehydroxylated silica, forming covalently immobilized metallocene catalysts. This dissertation concerns the synthesis of electrophile-functionalized zirconocene dihalide complexes and the use of functionalized zirconocene dihalides as precursors to silica-supported metallocene olefin polymerization catalysts. Our first objective was to extend the metallocene "functionalization" chemistry to obtain substituents bearing more than one electrophilic bond. The reactivities of Me3Sn and Ph2MeSi substituents were explored in detail. (Me3Sn)2C5H4 combined with CpZrCl3 in toluene to afford (h5-Me3Sn-C5H4)CpZrCl2 (A). Reactions of A with electrophiles (E-X = Cl2B-Cl, I-Cl, and I-I) afforded (ï ¨5-XMe2Sn-C5H4)CpZrCl2 (and E-Me) cleanly. The reaction of A with BBr3 afforded either (ï ¨5-BrMe2Sn-C5H4)CpZrBr2 (25 ï °C, 10 min) or (ï ¨5-Br2MeSn-C5H4)CpZrBr2 (25 ï °C, 15 h). Ph2MeSi-C5H4Li combined with ZrCl4·2THF to afford (h5-Ph2MeSi-C5H4)2ZrCl2 (B). The reaction of B with BCl3 led to incomplete cleavage of the Ph-Si bonds, however treatment of B with BBr3 afforded (h5-Br2MeSi-C5H4)2ZrBr2 (C) efficiently. The Sn-X bonds of the stannylated metallocenes were however relatively unreactive toward water and were excluded as candidates precursors for supported metallocene catalysts. X-ray crystal structures of (h5-ClMe2Sn-C5H4)CpZrCl2·½toluene, (h5-Br2MeSn-C5H4)CpZrBr2·THF, B, and C were obtained. The functionalized metallocene C reacts with water to afford an oligosiloxane-supported zirconocene dibromide. Combinations of solution 1H NMR, solid state CPMAS 13C NMR, and solid state CPMAS 29Si NMR spectroscopy suggested a stereoregular structure in which the metallocene units have local Cs (meso) symmetry. Although only sparingly soluble, the oligomeric substance showed activity for homogeneous ethylene polymerization (toluene solution, MAO cocatalyst, Al:Zr = 5000, 50 ï °C) similar to Cp2ZrCl2. Supported metallocene olefin polymerization catalysts were prepared by combining a functionalized metallocene precursor (Cp2ZrBr2 bearing either BrMe2Si or Br2MeSi groups) and partially dehydroxylated silica. Ethylene polymerization activity of the resulting catalysts was examined as a function of the precursor structure (number of reactive "tethering" groups, one vs. two Si-Br bonds per tethering group) and the immobilization conditions (time, temperature, presence or absence of NEt3 promoter). The activities of the immobilized zirconocene catalysts decreased and the stabilities increased with increasing number of tethers. The immobilized catalyst prepared from (ï ¨5-Br2MeSi-C5H4)2ZrBr2, which is assumed to form two "double-tethers" to silica, was significantly more active than the catalyst prepared from [ï ¨5-1,3-(BrMe2Si)2C5H3]2ZrBr2, which is assumed to form four "single-tethers" to silica. Catalyst leaching was observed in all the immobilized zirconocene catalysts. The use of NEt3 in the immobilization reaction enabled more metallocene to be supported, but the resulting activity was lower. The dissertation also includes model studies on the immobilization reaction and the stability of the Si-O-Si bonds. The reaction of C with tBuMe2SiOH results in the formation of Si-O-Si bonds; addition of NEt3 results in further reaction to afford Si-O-Zr bonds. The reaction of Reaction of Me3Si-O-SiMe3 with MAO showed that Si-O-Si bonds can be cleaved under the conditions of our polymerization reactions. / Ph. D.

[ES] Debido a la gran problemática que concierne el uso de plásticos, se ha incrementado la conciencia social derivada de los problemas medioambientales como la gran cantidad de desechos plásticos generados, la escasez de petróleo, el aumento de la huella de carbono y la contaminación. Como medida alternativa, aparece el uso de materiales de origen natural, consiguiendo reducir con éxito el uso de recursos no renovables y disminuir la cantidad de huella de carbono. Dentro de la industria del plástico, el polietileno de alta densidad (HDPE) es unos de los plásticos comerciales más utilizados, por lo que, el polietileno biobasado (BioHDPE), es una buena solución para reducir al máximo los problemas derivados de la utilización de recursos fósiles. El BioHDPE ofrece buena resistencia mecánica, alta ductilidad y resistencia al agua. Por otro lado, las cargas naturales se han utilizado desde hace mucho tiempo con el objeto de disminuir el coste del material. En la mayoría de los casos la introducción de estas cargas en porcentajes limitados no afecta de forma significativa a las prestaciones del material compuesto. En este trabajo de investigación, se pretende la obtención de nuevos materiales compuestos respetuosos con el medio ambiente a partir de una matriz polimérica (BioHDPE) con refuerzo de partículas de piña de pino para conseguir reducir los costes del uso del material virgen y, al mismo tiempo, mejorar sus propiedades. Debido a la naturaleza hidrofílica del HDPE, se introduce el copolímero el PE-g-MA con el fin de mejorar la interacción entre las fibras y la matriz. Obtenidas las mezclas en base a la variabilidad porcentual de carga, se realizan estudios de compatibilidad según sus propiedades a base de ensayos experimentales como mecánicos, térmicos, morfológicos, termomecánicos y tratamiento superficial con plasma atmosférico. Los resultados obtenidos permiten validar la obtención de "Wood Plastic Composites" en base a la incorporación de partículas de piña. La utilización de refuerzos de gran abundancia a un coste muy bajo como la piña de pino, ofrece la posibilidad de aumentar el rendimiento del compuesto obtenido. La utilización del compatibilizante PE-g-MA se muestra eficiente a la hora de mejorar las propiedades mecánicas dúctiles de los compuestos. La estabilidad térmica también mejora considerablemente con el uso del compatibilizante incluso con concentraciones mayores de piña. Con respecto al aspecto físico resultante de una pieza inyectada, se han obtenido muestras con un color marrón similar a la de algunas especies de madera natural. Se ha demostrado que la afinidad entre la matriz polimérica apolar y las partículas lignocelulósicas permite un incremento general de prestaciones en el compuesto resultante, lo que supone una notable reducción de coste en el producto final. Por todo ello, se demuestra que la afinidad entre la matriz polimérica apolar y las partículas lignocelulósicas permiten un incremento general de prestaciones en el compuesto. / [CA] A causa de la gran problemàtica que concerneix l'ús de plàstics, s'ha incrementat la consciència social derivada dels problemes mediambientals com la gran quantitat de deixalles plàstiques generades, l'escassetat del petroli, l'augmentant l'empremta de carboni i la contaminació. Com a mesura alternativa, apareix l'ús de material de base biològica, aconseguint reduir amb èxit l'ús de recursos no renovables i disminuir la quantitat d'emprempta de carboni. Dins la industria del plàstic, el polietilè d'alta densitat (HDPE) és un dels plàstics comercials més utilitzats, per la qual cosa, el politilè de base biològica (BioHDPE) és una bona solució per a reduir al màxim els problemes derivats de la utilització de recursos fòssils. El BioHPDE té bona resistencia mecànica, alta ductilitat i resistencia a l'aigua. D'altra banda, les càrregues naturals s'han utilitzat des de fa molt de temps per tal de disminuir el cost del material. En la majoria dels casos, la introducció d'aquestes càrregues en percentatges limitats no afecta de manera significativa a les prestacions del material compost. En aquest treball de'investigació, es pretén obtener nous materials compostos respectuosos amb el medi ambient a partir d'una matriu polimérica (BioHDPE) amb reforç de partícules de pinya de pi per aconseguir reduir els costos de l'ús del material verge i, al mateix temps, millorar les propietats. A causa de la naturalesa hidrofílica del HDPE, s'introduiex el copolímer PE-g-MA per a millorar la interacción entre les fibres i la matriu. Obtingudes les mescles en base a la variabilitat percentual de càrrega, es realitzen estudis de compatibilitat segons les seues propietats a base d'assajos experimentals com els mecànics, tèrmics, morfològics, termomecànics i tractament superficial amb plasma atmosfèric. Els resultats obtinguts permeten validar l'obtenció de "Wood Plastic Composites" en base a la incorporació de particules de pinya. La utilització de reforços de gran abundancia a un cost molt baix com la pinya de pi ofereix la possibilitat d'augmentar el rendiment del compost obtingut. La utilització del compatibilitzant PE-g-MA es mostra eficient a l'hora de millorar les propietats mecàniques dúctils dels compostos. L'estabilitat tèrmica també millora considerablement amb l'ús del compatibilitzant fins i tot amb concentracions més grans de pinya. Pel que fa a l'aspecte físic resultant d'una peça injectada, s'han obtingut mostres amb un color marró semblant a algunes espècies de fusta natural. S'ha demostrat que l'afinitat entre la matriu polimèrica apolar i les partícules lignocel.lulòsiques permet un increment general de prestacions en el compost resultant, fet que suposa una notable reducció de cost en el producte final. Per tot això, es demostra que l'afinitat entre la matriu polimérica apolar i les partícules lignocel.lulòsiques permeten un increment general de prestacions en el compost. / [EN] Due to the great problem that concerns the use of plastics, there has been an increase in social awareness derived from environmental problems based on the large amount of plastic waste generated, the scarcity of oil, the increasing the carbon footprint and the pollution. As an alternative measure, the use of bio-based materials appears, successfully reducing the use of non-renewable resources and reducing the amount of carbon footprint. Within the plastics industry, high-density polyethylene (HDPE) is one of the most widely used commercial plastics. Therefore, bio-based polyethylene (BioHDPE) is a good solution to minimize the problems derived from it of the use of fossil resources. BioHDPE has good mechanical, strength, high ductility and water resistance. On the other hand, natural fillers have been used for a long time in order to reduce the cost of the material. In most cases, the introduction of these loads in limited percentages does not significantly affect the performance of the composite material. In this research work, the aim is to obtain new environmentally friendly composite materials from a polymer matrix (BioHPDE) with reinforcement of pine cone particles to reduce the costs of using the virgin material and improve its properties. Due to the hydrophilic nature of HDPE, the PE-g-MA copolymer is introduced in order to improve the interaction between the fibers and the matrix. Once the mixtures are obtained based on the percentage variability of load, compatibility studies are carried out according to their properties based on experimental tests such as mechanical, thermal, morphological, thermomechanical and surface treatment with atmospheric plasma. The results obtained allow us to validate the production of Wood Plastic Composites based on the incorporation of pine particles. The use of highly abundant reinforcements at a very low cost, such a pine cone, offers the possibility of increasing the performance of the compound obtained. The use of PE-g-MA compatibilizer is shown to be efficient in improving the ductile mechanical properties of the compounds. The thermal stability also improves considerably with the use of the compatibilizer even with higher concentrations of pine. Regarding the resulting physical appearance injected piece, samples have been obtained with a brown color similar to that some species of natural wood. It has been shown that the affinity between the nonpolar polymeric matrix and the lignocellulosic particles allows a general increase in performance in the resulting composite, which represents a notable cost reduction in the final product. For all this, it is demonstrated that the affinity between the nonpolar polymer matrix and the lignocellulosic particles allows a general increase in performance in the composite. / Morcillo Esquerdo, MDC. (2023). Desarrollo y optimización de mezclas de alto rendimiento medioambiental basadas en poliolefinas y cargas de origen natural [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/202559

京都大学 / 新制・課程博士 / 博士(工学) / 甲第23922号 / 工博第5009号 / 新制||工||1782(附属図書館) / 京都大学大学院工学研究科高分子化学専攻 / (主査)教授 竹中 幹人, 教授 古賀 毅, 教授 中村 洋 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

<p>Low molecular weight functionalized polyolefins are mainly used as additives in adhesive formulations, compatibilizing agents and aqueous dispersions. However, the low viscosity and functionality they offer has never been explored to generate high molecular weight products that offer improved processing routes for polyolefins as well as wider applications.</p> <p>The aim of this thesis work was to investigate the preparation and characterization of thermoset material by reactions between a highly functionalized, low viscosity maleic anhydride grafted polyethylene and diamines. Reactions were performed both in solution and in the melt state to generate the target thermoset materials. Products from these reactions were extensively explored using different techniques to understand the reaction kinetics and mechanism. Thermosets generated were also characterized for the degree of crosslinking, thermal, mechanical and thermomechnical properties.</p> <p>Reactions in solution showed that the degree of reaction could be easily controlled by manipulating the concentration of reactants in the reaction mixture. Mixing torque data from the melt blender generated during reactions in the melt phase suggested that reaction between anhydride and amine moieties in these systems happen at much slower rate than widely reported for conventional high molecular weight polymeric systems. Unlike a single or two closely merged peaks in mixing torque associated with melting of polymer and chain extension and crosslinking due to reaction between anhydride and amine functionality widely reported, two separate peaks were observed in this study. A combination of FTIR and insoluble fraction data generated suggested that the first peak observed in mixing torque represents a combination of melting and partial reaction between anhydride and amine functionality. Whereas, the second peak in the mixing torque represents the initiation of crosslinking. The slower kinetics observed in the current investigation was found not to be a consequence of immiscibility of polyether diamine and polyethylene or the relatively higher molecular weight of diamines utilized in some reactions since using a low molecular weight aliphatic diamine, hexamethylenediamine, produced similar trends. FTIR and gel content (insoluble fraction) data generated on the prepolymers by processing them at high temperatures, suggested residual anhydride presence in products which could not be assessed using FTIR. This observation renders the popular monitoring of anhydride peak in such systems to assess the degree of reaction highly questionable. Cured thermosets from the prepolymers produced showed gel fractions of the same scale as in traditional crosslinked products. DSC heat scans on the thermosets showed separate crystal populations for polyethylene in cured and uncured fraction. Dynamic mechanical analysis result showed the thermosets withstood temperature up to 200 °C without failure and a crosslink plateau could be observed following the melting transition. Tensile properties of the thermosets were observed to be promising and composition dependent.</p> <p>These thermosets are expected to extend the polyolefins applications in areas like sealant, adhesive and coatings. The low viscosities of starting materials could also lead to new processing routes for polyolefins.</p> / Doctor of Philosophy (PhD)