|
|
Lightweight composite materials for automotive applications
Sousedík, Jan ; Poláček, Petr (referee) ; Přikryl, Radek (advisor)
This bachelor thesis investigated the influence of lightening filler in the form of hollow glass microbeads on the mechanical properties of composite material. The method chosen for the preparation of composite material was pultrusion. Two types of composite material were prepared as part of the bachelor thesis, specifically epoxy-vinyl ester resin-based composites and unsaturated polyester resin-based composites. Special bulked glass fibres were used as reinforcement. The final composite material was subjected to a three-point flexural test where mechanical properties were monitored. In addition, control of the distribution and adhesion of the filler was performed by using light microscopy and scanning electron microscopy (SEM).
|
|
|
Additive in unsaturated polyester resin for pultrusion process
Vaněk, Martin ; Bábík, Adam (referee) ; Přikryl, Radek (advisor)
Theoretical part of bachelor’s thesis deals with composite materials based on fiberglass and unsaturated polyester resins. It focuses on Low profile aditives, which are added in matrix to lower polymerization shrinkage. The thesis studies the influence of additives on the changes of matrix behavior and mechanical composite properties. Nature of those changes was monitored by differential scanning calorimetry (DSC), scanning electronmicroscopy (SEM), touchscreen profilometry, tensile test and bending test. Influence of LPs on matrix polymerization shrinkage, roughness and geometry in fiberglass composites were evaluated. Matrix Polipol 3870 and aditive Norsolook A71074 were found to be the most suitable because the best result was observed.
|
|
|
Inorganic flame retardants and their application in composites
Bergmann, Ondřej ; Kučera, František (referee) ; Poláček, Petr (advisor)
In the first part of this bachelor thesis frequently used fire retardant additives are described as well as their mechanisms of action and the most common methods of flammability characterization. In the second experimental part the influence of two systems, consisting of a matrix and two fillers in different ratios, on viscosity, thermal stability and flammability were examined. Unsaturated polyester resin was used as the matrix. The first filler was always a fire retardant based on aluminium hydroxide, which was combined with the second filler based on either ammonium polyphosphate, or melamine polyphosphate. Viscosity of these samples was determined and casts for further analyses were made. Casts were analysed with thermogravimetric analysis and by flammability tests. Generally, with higher filler content the samples were more viscous, thermally degraded at lower temperatures and had better fire characteristics.
|
|
|
Composites based on natural fibers
Hahn, Filip ; Poláček, Petr (referee) ; Přikryl, Radek (advisor)
The theoretical part of this bachelor thesis deals with current state of art in the field of composite materials based on natural fibers and polymer matrices, and with production methods of the composite materials. The practical part focuses on the testing of the mechanical properties of sisal and flax fibers and on their chemical treatment by NaOH solution. The above mentioned fibers and unsaturated polyester resin were used to produce composite materials by means of pultrusion process. The flexural properties of the material samples were tested and compared to those of glass fiber composites.
|
|
|
Composite materials with enhanced coefficient of linear attenuation of ionizing radiation
Novotný, Kamil ; Petruš, Josef (referee) ; Kučera, František (advisor)
Ionizing radiation has many useful applications in the fields of healthcare, food industry, nuclear energy and others but poses a hazard to human health in higher doses. In this work, composite materials with enhanced ionizing radiation attenuation properties were prepared. Unsaturated polyester resin was reinforced with inorganic fillers containing elements such as bismuth or barium. Morphology of the samples was studied using scanning electron microscopy. Theoretical values of mass attenuation coefficients were obtained for photon energies 662 keV and 1253 keV using the XCOM software. The attenuation of ionizing gamma radiation was experimentally measured using radioactive sources 137Cs and 60Co. Linear attenuation coefficients and half value layers of the materials were determined using the obtained data. Addition of the fillers improved the shielding properties of the matrix. Composite containing bismuth oxide achieved the highest values of linear and mass attenuation coefficients. The experimental results were found to be in good agreement with theoretical values. Moreover, influence of the fillers on impact toughness has been evaluated.
|
|
|
Inorganic flame retardants and their application in composites
Bergmann, Ondřej ; Kučera, František (referee) ; Poláček, Petr (advisor)
In the first part of this bachelor thesis frequently used fire retardant additives are described as well as their mechanisms of action and the most common methods of flammability characterization. In the second experimental part the influence of two systems, consisting of a matrix and two fillers in different ratios, on viscosity, thermal stability and flammability were examined. Unsaturated polyester resin was used as the matrix. The first filler was always a fire retardant based on aluminium hydroxide, which was combined with the second filler based on either ammonium polyphosphate, or melamine polyphosphate. Viscosity of these samples was determined and casts for further analyses were made. Casts were analysed with thermogravimetric analysis and by flammability tests. Generally, with higher filler content the samples were more viscous, thermally degraded at lower temperatures and had better fire characteristics.
|
|
|
Lightweight composite materials for automotive applications
Sousedík, Jan ; Poláček, Petr (referee) ; Přikryl, Radek (advisor)
This bachelor thesis investigated the influence of lightening filler in the form of hollow glass microbeads on the mechanical properties of composite material. The method chosen for the preparation of composite material was pultrusion. Two types of composite material were prepared as part of the bachelor thesis, specifically epoxy-vinyl ester resin-based composites and unsaturated polyester resin-based composites. Special bulked glass fibres were used as reinforcement. The final composite material was subjected to a three-point flexural test where mechanical properties were monitored. In addition, control of the distribution and adhesion of the filler was performed by using light microscopy and scanning electron microscopy (SEM).
|
|
|
Additive in unsaturated polyester resin for pultrusion process
Vaněk, Martin ; Bábík, Adam (referee) ; Přikryl, Radek (advisor)
Theoretical part of bachelor’s thesis deals with composite materials based on fiberglass and unsaturated polyester resins. It focuses on Low profile aditives, which are added in matrix to lower polymerization shrinkage. The thesis studies the influence of additives on the changes of matrix behavior and mechanical composite properties. Nature of those changes was monitored by differential scanning calorimetry (DSC), scanning electronmicroscopy (SEM), touchscreen profilometry, tensile test and bending test. Influence of LPs on matrix polymerization shrinkage, roughness and geometry in fiberglass composites were evaluated. Matrix Polipol 3870 and aditive Norsolook A71074 were found to be the most suitable because the best result was observed.
|
|
|
Composites based on natural fibers
Hahn, Filip ; Poláček, Petr (referee) ; Přikryl, Radek (advisor)
The theoretical part of this bachelor thesis deals with current state of art in the field of composite materials based on natural fibers and polymer matrices, and with production methods of the composite materials. The practical part focuses on the testing of the mechanical properties of sisal and flax fibers and on their chemical treatment by NaOH solution. The above mentioned fibers and unsaturated polyester resin were used to produce composite materials by means of pultrusion process. The flexural properties of the material samples were tested and compared to those of glass fiber composites.
|
|
| |
guest ::
