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Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 343 for “"Polymerisation"”.
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Polymerisation in Miniemulsion
Der Mechanismus der Miniemulsionsbildung bzw. polymerisation wird eingehend untersucht. Dabei werden Faktoren, wie die Tensidmenge, Ultraschalldauer und die Teilchengröße untersucht. Besonders werden auch noch Aspekte wie Stabilität der Emulsion und Kinetik während der Polymerisation untersucht.
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Studies in Metathesis Polymerisation
The WCl6 / AliBu3 initiated polymerisation of cyclopentene has been investigated as a chain reaction and attempts have been made to study the reactions of the chain, ie initiation, propagation and termination. The reactions between alkenes and tungsten hexachloride at low molar ratios of alkene : W …
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New Pre-Catalysts for Olefin Polymerisation and Ring-Opening Polymerisation of Lactides/Lactones
… screening of group 5 compounds 1 – 50 for the polymerisation of α-olefins revealed high activity, significantly in the case of the niobium precatalysts which were two orders of magnitude above the previously reported compounds. The reactions between 1,3-dipropoxy-p-tert-butyl-calix[4]arene …
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Wässerige Polyethendispersionen durch katalytische Polymerisation
… der vorliegenden Arbeit wurde die katalytische Polymerisation zu Polyolefinen in wässerigen Systemen durch Nickel-Katalysatoren untersucht. Es konnten stabile Dispersionen von Polyethenen hergestellt werden. Die Partikelmorphologie und das thermische Verhalten der Polymerdispersionen wurde …
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Metathetic Polymerisation of Cyclic Alkenes
The monometallic initiation of the ring opening polymerisation of cyclopentene as a solution in toluene or chlorobenzene has been investigated by dilatometric and calorimetric techniques using WC16or WC16/02, as the catalyst. These studies indicated the occurrence of a series of reactions between …
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Scale-up in emulsion polymerisation
… for successful scale-up of batchwise emulsion polymerisation has been studied. The relevant literature on liquid-liquid dispersion on scale-up and on emulsion polymerisation has been crit1cally reviewed. Batchwise emulsion polymerisation of styrene in a specially built 3 litre, unbaffled, …
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Aspects of Suspension & Emulsion Polymerisation
Suspension polymerisation involves a dynamic equilibrium between monomer break up and coalescence.<br/><br/>A water soluble polymer (the suspending agent) is added to the aqueous phase to stabilise the monomer drop form during its conversion to a solid reaction product. Depending on the type and …
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The Polymerisation of Sulphur containing Heterocycles
… reaction a competition was observed between polymerisation and formation of tetramethyl thioglycollide. The overall kinetics of the reaction were studied by both gas evolution and spectroscopic techniques. The proposed mechanism involves the primary decomposition of the ring in a first-order …
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Koordinationschemische Untersuchungen zur syndiotaktischen Polymerisation von Styrol
… eines Verfahrens zur syndiotaktischen Polymerisation von Styrol unter Verwendung von diesen homogenen Ziegler-Natta-Katalysatoren beigetragen. Im Rahmen dieser Arbeit wurden neuartige Katalysatoren zur Gewinnung von syndiotaktischem Styrol entwickelt. Dazu wurden einerseits besonders …
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Graft polymerisation of antioxidants into natural rubber
Antioxidants containing polymerisable vinyl groups have been successfully bound to natural rubber in the presence of suitable free radical generators. Reaction parameters such as the mode of initiation, initiator system, reaction time, pH of the reaction medium, swelling time have been investigated …
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Toca-1 driven actin polymerisation at membranes
… of the F-BAR protein Toca-1 in linking actin polymerisation to membranes, by characterising a new protein-protein interaction and the interaction of Toca-1 with giant unilamellar vesicles. FBP17, a homologue of Toca-1, can oligomerise to form 2D flat lattices and 3D tubules on membranes. …
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Neue Katalysatorsysteme für die Vinyl-Polymerisation von Norbornen
… der Metalle Ni, Pd und Co wurden für die Vinyl-Polymerisation von Norbornen erschlossen. Die Aktivierung erfolgte mit MAO, mit Tris(pentafluorphenyl)boran, B(C6F5)3 und mit B(C6F5)3/Triethylaluminium (AlEt3). <br>Ein Wechsel von MAO zu B(C6F5)3 bzw. B(C6F5)3/AlEt3 ermöglicht die Untersuchung des …
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Studies on the Ring Opening Polymerisation of Cyclopentene
… on the initiation and the propagation of the polymerisation of cyclic alkenes catalysed by tungsten based systems. Cyclopentene was polymerised using the bimetallic WCl₆/Al(iBu)₃ catalyst and infra-red spectroscopy showed that trans-polypentenamer was formed. A kinetic chain mechanism was …
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Computer-Guided Design of Photocatalyst for PET-RAFT Polymerisation
Photo-controlled polymerisation uses a photo-excited photocatalyst (PC) to reversibly and deactivate the propagating species. Under regulation by light, photo-controlled polymerisation features temporal control, spatial control, sequence control and high level of selectivity/orthogonality between …
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Characterization and computational modelling of acrylic bone cement polymerisation
… damage. Residual stresses generated during the polymerisation of the cement are now thought to play a significant role in cement failure. This thesis examines the development of residual stresses as a result of thermal and chemical changes during polymerisation of the cement. Experimental …
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Neuartige Phosphoniumkatalysatoren für die anionisch ringöffnende Polymerisation von Propylenoxid
… behandelt die anionisch ringöffnende Polymerisation (ROP) von Propylenoxid mittels sterisch anspruchsvoller Iminophosphoniumkatalysatoren (P1). Durch Kontaktionenpaarseparation sollte die Polymerisationsaktivität und die Bildung von Allylethern als Nebenreaktion positiv beeinflusst …
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Some aspects of free radical polymerisation in UV-curing
… as synergist, were used to initiate the polymerisation of acrylates. It was found that the quinoxalines where used with amine synergist are efficient Type II initiators. It was also found that the cure of the acrylate is faster when oxygen is present in the reaction mixture than when it …
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