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Effect of alternative agents on controlled degradation of polypropylene
Kadlecová, Zuzana ; Figalla, Silvestr (referee) ; Bílek, Vlastimil (advisor)
This bachelor’s thesis focuses on the effect of degradation agents in controlled rheology polypropylene and its efficiency. That was evaluated on several types of polypropylene with different molecular weight, the strength of stabilization and content of degradation reagents (organic peroxide and nitroxide Irgatec® CR 76). Melt flow rate, rheometry, and molecular weight distribution methods were applied. Results of each method for unstabilized, stabilized polypropylene and polypropylene containing degradation agent were compared. It was determined, that higher polymer chain degradation efficiency is provided by organic peroxide, lower by nitroxide. The molecular weight distribution of polypropylene was much narrower with peroxide than with nitroxide even though it should have been conversely according to published data. The molecular weight distribution of polypropylene (Mw/Mn) was much narrower with nitroxide than with peroxide at all process temperatures.
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Determination and evaluation of cosmetic ointment and design of label according to actual legislation
Trávníčková, Eva ; Bečica, Aleš (referee) ; Souralová Popelková, Miriam (advisor)
This diploma thesis is focused on the study olephylic formulations – ointments and cream type of V/O. This thesis gives out information about production, use and properties 3 cosmetic ointments and about properties baby´s skin cream and the study of stability of these products in the presence of antioxidants - tocopherol acetate and rosemary extract. Ointments are made from hemp oil, olive oil and shea butter and chamomile extract. Each ointment is produced in two versions. Once the use of vitamin E as an antioxidant, a second is used as an antioxidant extract from rosemary. Among other important substances with positive effects on human skin include, for example, saturated fatty acids such as palmitic acid and stearic acid, unsaturated fatty acids such as oleic, linoleic, and more. Ointments are suitable for greasing dry to very dry skin hands, face and other body parts. The thesis also discusses the current legislation, which producer of cosmetics must comply, the details which must be placed on the label of a cosmetic product and it contains proposals of cosmetic labels Further thesis includes studying methods for determination of lipid characterizations were used for study of behaviour of ointments during time and during storage at different temperatures. They include iodine, acid, peroxide and saponification values. The ester value and the content of glycerol were counted.
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Effect of alternative agents on controlled degradation of polypropylene
Kadlecová, Zuzana ; Figalla, Silvestr (referee) ; Bílek, Vlastimil (advisor)
This bachelor’s thesis focuses on the effect of degradation agents in controlled rheology polypropylene and its efficiency. That was evaluated on several types of polypropylene with different molecular weight, the strength of stabilization and content of degradation reagents (organic peroxide and nitroxide Irgatec® CR 76). Melt flow rate, rheometry, and molecular weight distribution methods were applied. Results of each method for unstabilized, stabilized polypropylene and polypropylene containing degradation agent were compared. It was determined, that higher polymer chain degradation efficiency is provided by organic peroxide, lower by nitroxide. The molecular weight distribution of polypropylene was much narrower with peroxide than with nitroxide even though it should have been conversely according to published data. The molecular weight distribution of polypropylene (Mw/Mn) was much narrower with nitroxide than with peroxide at all process temperatures.
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Determination and evaluation of cosmetic ointment and design of label according to actual legislation
Trávníčková, Eva ; Bečica, Aleš (referee) ; Souralová Popelková, Miriam (advisor)
This diploma thesis is focused on the study olephylic formulations – ointments and cream type of V/O. This thesis gives out information about production, use and properties 3 cosmetic ointments and about properties baby´s skin cream and the study of stability of these products in the presence of antioxidants - tocopherol acetate and rosemary extract. Ointments are made from hemp oil, olive oil and shea butter and chamomile extract. Each ointment is produced in two versions. Once the use of vitamin E as an antioxidant, a second is used as an antioxidant extract from rosemary. Among other important substances with positive effects on human skin include, for example, saturated fatty acids such as palmitic acid and stearic acid, unsaturated fatty acids such as oleic, linoleic, and more. Ointments are suitable for greasing dry to very dry skin hands, face and other body parts. The thesis also discusses the current legislation, which producer of cosmetics must comply, the details which must be placed on the label of a cosmetic product and it contains proposals of cosmetic labels Further thesis includes studying methods for determination of lipid characterizations were used for study of behaviour of ointments during time and during storage at different temperatures. They include iodine, acid, peroxide and saponification values. The ester value and the content of glycerol were counted.
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