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This thesis deals with the mechanisms of microstructure development in polymer blends. Much work has been performed on the breakup process of immiscible systems where the dispersed phase is suspended inside another matrix. The fluids used were polymer melts or model viscoelastic fluids, and the processing flows were model shear flow or processing flows seen in industry. It is found that in industrial extruders or batch mixers, the morphology of the dispersed polymer evolves from pellets to films, and subsequently to fibers and particles. In this thesis, it is demonstrated based on force analysis that the in-situ graft reactive compatibilization facilitates breakup of the dispersed phase by suppressing slip at the interface of the dispersed phase and matrix phase. The morphology development of polymer blends in industrial mixers was simulated by performing experiments of model viscoelastic drop deformation and breakup under shear flow. Two distinct modes of drop deformation and breakup were observed. Namely, viscoelastic drops can elongate and breakup either in (1) the flow direction or (2) the vorticity direction. The first normal stress difference N1 plays a decisive role in the conditions and modes of drop breakup. Drop size is an important factor which determines to a great extent the mode of drop breakup and the critical point when the drop breakup mechanism changes. Small drops break along the vorticity direction, whereas large drops break in the flow direction. A dramatic change in the critical shear rate was found when going from one breakup mode to another. Polymer melts processed under shear flow present different morphology development mechanisms: films, fibers, vorticity elongation and surface instability. The mechanisms depend greatly on the rheological properties of both the dispersed and matrix phases, namely the viscosity ratio and elasticity ratio. High viscosity ratio and high elasticity ratio result elongation of the dispersed phase in the vorticity direction. Medium viscosity ratio and low elasticity ratio result in fiber morphology. Low viscosity ratio and high elasticity ratio result in film morphology. The surface instability is caused by the shear-thinning effect of the dispersed polymer. / Chemical Engineering

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Keywords "Long" 18th century; 18th century; Baroque; Enlightenment; Czech National Revival; history of Czech language; development of Czech language; Czech language in the Baroque period; Czech language in the times of the Czech National Revival; Czech language in the "long" 18th century; manuscript; scribe's usage; cultural Czech language; books of historiographic records; historiography; "folk chronicles"; gramatography; grammar books; Baroque stylistics; Baroque rhetoric; history of spelling; development of spelling; history of phonetics; development of phonetics; history of morphology; development of morphology; development of the lexis; Chlumec nad Cidlinou; Kutná Hora; Milčice; Nové Strašecí; Pelhřimov; Roudnice nad Labem; František Šolc; Vojtěch Kegler; František Jan Vavák; Filip Ignác Dremsa; Antonín Štěpán; Vojtěch Jílek; Václav Preinhelter. Abstract The traditional view describing Czech literary works written in the period from the late 17th century to the end of 18th century as signs of decline in the level of Czech language and literature has been successfully overcome by linguists over the past few decades. However, most papers covering the topic were focused on prints; handwritten sources are being analysed marginally and unsystematically. The aim of this dissertation is to provide a more...