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High Performance Polymer Composites
Bábík, Adam ; Lapčík,, Lubomír (referee) ; Prokeš, Jan (referee) ; Čech, Vladimír (advisor)
High performance polymer composites are materials with emphasis on specific chemical and mechanical properties due to their broad scope of applications. The main advantages are high strenght and toughness in comparison with their low weight and density. An increased adhesion at composite interfaces is important to ensure excellent composite properties. Bundles of glass fibers were coated by plasma-polymerised interlayers of tetravinylsilane (pp-TVS) of different thicknesses and at different effective powers. The prepared interlayers of pp-TVS were analyzed to evaluate chemical composition (RBS, FTIR, XPS) and mechanical properties (NI-AFM). Microindentation test and fiber-bundle pull-out test were used to determine the interfacial shear strenght.
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Mechanical response of long-fiber-reinforced polymer composite
Škriniarová, Nina ; Prokeš, Jan (referee) ; Čech, Vladimír (advisor)
This diploma thesis is focused on monitoring of mechanical response of long-fiber reinforced polymer composite. Main part of this thesis was preparation of long-fiber reinforced composite specimens, on which matrix was reinforced by commercially sized glass fibers. For comparison of properties were prepared specimens reinforced by unsized glass fibers. Apart from preparing specimens reinforced by long glass fibers were prepared specimens contains long carbon fibers. For evaluation of mechanical response of the prepared composite specimen were used flexural test and short beam shear test. Mechanical response was evaluated with universal testing machine ZWICK Z010 and data were processed in OriginPro 8 program. Thanks to evaluation of the mechanical response of the prepared specimens was assessed adhesion to fiber-matrix interface. By examining the mechanical response or adhesion can be assessed efficiency of commercial fiber surface treatment and so standardize measurement to compare other options of surface treatments.
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Thermoplastic composites for automotive applications
Zbončák, Marek ; Pospíšil,, Ladislav (referee) ; Jančář, Josef (advisor)
Diplomová práca sa zaoberá prípravou teromplastických kompzoitov s PMMA a PC matricou s potenciálnym využitím v automobilovom priemysle. Ako výstuž boli použité krátke sklenené, uhlíkové a PBO (poly(p-fenylén benzobisoxazol)) vlákna známe pod obchodným názvom Zylon®. Práve do PBO vlákien boli vkladané veľké nádeje vzhľadom na ich ohromujúce mechanické vlastnosti. Vplyv objemového zlomku vlákien na modulu pružnosti, pevnosť a ťažnosť kompozitov bol skúmaný. Experimentálne zistený modul pružností bol porovnaný so semi-empirickým Halpin-Tsai modelom. Prídavok sklenených a uhlíkových vlákien viedol k značnému zvýšeniu modulu pružnosti. Ukázalo sa, že po istej hodnote objemového zlomku dochádza k poklesu pevností kompozitov v dôsledku zvyšujúceho sa počtu defektov. Prídavok PBO vlákien preukázal len nepatrný vystužujúci efekt. Viskoelastické vlastností kompozitov boli skúmané pomocou dynamicko mechanickej analýzy (DMA). Termogravimetrická analýza (TGA), konfokálna laserová rastrovacia mikroskopia (CLSM) a rastrovacia elektrónová mikroskopia (SEM) boli využité k štúdiu štruktúry kompozitov.
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The optimalization of clay building components
Melichar, Jindřich ; Šiler, Pavel (referee) ; Opravil, Tomáš (advisor)
Clay building components are nowadays one of the most used building materials in the world. Except easy availability and processability clay building components have also heat storage function. This master´s thesis will be considering possibilities of improving thermal and mechanic properties of these materils by additing suitable reinforcements.
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Mineral wool and binding agent interaction and behavior study
Fiala, Michal ; Šoukal, František (referee) ; Ptáček, Petr (advisor)
Diploma's thesis describes resolution of cause technological problems in mineral wool manufacturig in company Saint-Gobain Orsil. Main attention is paid to thermal and volatile process in mineral wool from filtration chamber and common commercial sales. Samples of mineral wool were characterizated by thermal analysis (simultaneous TG-DTA), effluent gas analysis (EGA), infrared spectroscopy (FT-IR), electron microscopy (SEM) and X-ray diffraction (XRD). Thermal analysis experiments was used to check thermal volatile processes. Technological problem of burning is linked with rise of isocyanic acid.
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Properties of pultruded composites based on epoxy matrix
Huljak, Pavel ; Bálková, Radka (referee) ; Přikryl, Radek (advisor)
The theoretical part of this bachelor thesis deals with research of composite materials, especially based on polymer epoxy and polyester resins, using as reinforcement a glass fiber bundles. The practical section includes the production of composite materials and their components along with the most important testing methods. The main goal of the experimental part is to characterize the optimal conditions pultrusion production of epoxy composite material. Another point is characterization of mechanical and chemical properties of the produced composite at a number of test methods. Finally the optimized epoxy composite materials are compared with composites based on polyester resins.
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Preparation of PP composites by grafting using monomer treated filler
Kramerová, Nina ; Žídek, Jan (referee) ; Kučera, František (advisor)
Bachelor thesis is focused on preparation of composite materials with polypropylene matrix. The composites were prepared “in situ” with using Brabender mixer. Homogenization of matrix and filler and grafting of PP with anhydride of itaconic acid treated filler proceed together according to radical mechanism of polymerization. Luperox 101 [2,5-dimethyl-2,5-di(tertbutyl-peroxy)hexane] was used as an initiator of the reaction, the concentration of the initiator was 0.5 wt %, processing temperature 210 °C, 30 rpm. PP-g-IA is a compatibilizer between the matrix and the filler. Glass fibers, calcite and two types of ground wood pulp were used as filler. Two analytical methods were chosen to analyze the efficiency of grafting, acid-base titration and infrared spectroscopy. Assigned conversion of monomer was from 42 to 87 % for various fillers.
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Some surface improvement and osseointegration
Suchý, T. ; Balík, Karel ; Sedláček, R. ; Sochor, M.
As a further perspective material to be used in orthopedics, glass fibers (R-glass, 21055 satin-woven fabric, VETROTEX, Saint Gobain, France) and polysiloxane matrix (M130, Lučební závody Kolín, Czech Republic) based composite materials have been investigated.
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Porous composites based on siloxane resin for hard tissue replacements
Suchý, T. ; Balík, Karel ; Sochor, M. ; Černý, Martin ; Hulejová, H. ; Pešáková, V.
A composite material based on polysiloxane and first on glass fabrics was prepared. The composite samples were prepared with controlled open porosity, the sizes of which were in the range: i) 0,2-0,4 mm, ii) 0,4-0,6 mm, and iii) >0,6 mm. For further improvement of osseointegration, a powder hydroxyapatite, particle size of 0,005 mm in the amount of 10 wgt %. The effects of surface treatment and hydroxyapatite matrix additives on osseointegration were studied by methods in vitro and in vivo.
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