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The aim of this work was to encapsulate two drugs: 5-Fluorouracil (5-FU) with the hydrophobic properties and 5-Formyl-5,6,7,8-tetrahydropteroyl-L-glutamic acid calcium salt (leucovorin) with the hydrophilic properties into liposomes prepared by the modified reverse-phase evaporation method (mREV) from L-α-phosphatidylcholine dipalmitoyl (DPPC). The drugs are used in the anticancer multidrug therapy FLv (5-fluorouracil, leucovorin) and ELF (etoposide, leucovorin, 5-fluorouracil). We studied the competition for their encapsulation in liposomes by the use of two spectroscopies: 1H NMR and UV on the basis of the analysis of the signals of each drug in the liposome - drug system. Liposomes are highly versatile structures for research, therapeutic and analytical applications. We concluded that the liposomes obtained by the mREV method may transport more than one drug simultaneously. [ABSTRACT FROM AUTHOR]

Properties of the polyurethane-rubber composites obtained from used products were studied. The influence of the amount of polyurethane glue and amount of isocyanate diphenylmethane 4,4′-diisocyanate (MDI) on composites selected properties was observed. The dynamic thermo-mechanical analysis allowed us to determine the glass transition temperature Tg and the course of the relaxation processes in the composites. The analysis of the changes in the storage module E′ and loss module E″as a function of temperature enabled the calculation of the activation energy for relaxation processes of various polyurethane glues and polyurethane-rubber composites. [ABSTRACT FROM AUTHOR]

Polymer materials packagings are quickly deposited in dumps due to the short life time as a useable product. Recycling of polymer waste, mainly polyolefines, which constitute 60% of them, on the technological lines operating according to the Polish technology seems to be a long-term solution. According to this technology, the used polymers after melting flow down to the reactor, where they undergo thermal degradation in the presence of catalyst. A product which can be processed in refineries for fuel is obtained. The studies leading to the improvement of the properties of the obtained product are still conducted. [ABSTRACT FROM AUTHOR]

In this study waste polystyrene foam and virgin polystyrene as a reference materials were converted by chemical reactions under heterogeneous conditions into useful products. Polymeric flocculants were obtained from polystyrene during the sulfonation with sulfuric acid as the sulfonating agent and Ag2SO4 as the catalyst. The influence of temperature and time of reaction on the properties of the products were studied. The products were successfully used as flocculants in the treatment of the waste water. Solid silica sulfuric acid was also used to convert polystyrene. In comparison with the conventional sulfonation methods this sulfonating agent simplifies the reaction and makes easier separation of products from acid and solvent. The obtained products were cross-linked and exhibited cation-exchange properties. The batch method was used to study purification of solutions of Zn2+ and Cu2+ by the yielded resins. The performed study proved the usefulness of waste polystyrene derivatives for water treatment process. [ABSTRACT FROM AUTHOR]

The aim of the investigation was the dynamic thermo-mechanical analysis (DMTA) study of the polyurethane-rubber composites obtained from used polymer products. Polyols obtained in the glycolysis process from used semi-rigid polyurethane foams, hardened by diphenylmethane 4,4'-diisocyanate (MDI) and rubber granules obtained from mechanical granulation of used car tyres were used to receive polyurethane-rubber composites. On the basis of the DMTA spectra the glass transition temperature Tg was determined. The analysis of loss module E'' allowed us to observe two relaxation processes for polyurethane-waste rubber composites α - originating from the rubber and α' - from the polyurethane glue. The dependence of the changes of activation energy of relaxation processes with the change of weight ratio of polyurethane glue in polyurethane-waste rubber composites was observed. [ABSTRACT FROM AUTHOR]

Used polymer plastics have high fuel values (approximately 40 MJ/kg for polyolefines). Therefore, they constitute perfect energy materials. Thermodestruction of used products and wastes of polymer plastics on specialized installations seems to be a long-term method to manage this group of wastes in chemical recycling with the destination to obtain fuel ingredients. Application of this technology allows for reduction the quantity of municipal waste. This enables also to obtain the valuable fuel components. In the Department of Environment Chemistry and Technology of Institute of Chemistry at the University of Silesia and in enterprises using the installation for the thermodestruction of used polymer plastics it was studied influence of different catalyst on course of thermodestruction. According to an innovatory technology elaborated in the enterprise called “Speranda-1” Sp. z o.o. the dirty used products of polymer plastics and wastes after melting flow down to the bottom part of the reactor, where they undergo thermal degradation due to a contact with the catalyst. It was ascertained that type of catalyst influences the course of the primary and secondary destruction processes and is of fundamental importance for capacity of this process and for the composition of the obtained products. [ABSTRACT FROM AUTHOR]

The study of polymer properties requires the synthesis and analysis of simple model compounds. The aim of this work was the synthesis and investigation one of model compounds are needed to perform the physicochemical characteristics of linear, branched and dendrite polyesters. The description of relaxations processes of model oligoesters can make it easier to interpret the dependence between the useful properties of polyesters and the molecular structure of their macromolecules. Instrumental methods as NMR, FTIR and dielectric spectroscopy, calorimetry (DSC), thermogravimetric analysis and mechanical spectroscopy are used to this goal. The structure of the synthesized tetrakis(5-hydroxypentyl)piromelite (oligoester) was confirmed with the use of NMR, FTIR spectroscopy and elemental analysis. A detailed study of the relaxation properties using broadband dielectric spectroscopy and Dynamic Mechanical Thermal Analysis (DMTA) was also performed. A description of different dielectric and DMTA α-relaxation processes for the oligoester are indispensable to determine the relaxation properties of the suitable polyesters. For the synthesized oligoester glass temperature (Tg), relaxation time (τ) and activation energy (Ea) were determined from the results of DSC, DMTA and dielectric spectroscopy. [ABSTRACT FROM AUTHOR]

Some oligoesters were synthesized in order to study changes of the useful properties of hyper-branched unsaturated polyesters. The determination of the polymer relaxation properties allows for characterization of their structure. Useful properties of the polymers such as stability and persistence depend on their structure. The aim of the investigation was to obtain model oligoesters with low molecular weight and to study their properties by spectroscopic and the dynamic mechanical thermal analysis (DMTA) methods. The synthesis was performed with the use of ethylene glycol and the mixture of maleic anhydride and phthalic acid which allowed us to obtain linear unsaturated polyesters. The cross-linking process of synthesized model oligoesters was performed using styrene as a cross-linking agent. The NMR and IR spectroscopy and elemental analysis were used for the description of purity and the structure of the obtained products. Relaxation properties of the synthesized oligoesters, course of their cross-linking and relaxation properties of the cross-linked products were studied by DMTA methods. In the synthesized oligoesters and cross-linked products α and β-relaxation processes were observed. [ABSTRACT FROM AUTHOR]

The degree of encapsulation of 5-fluorouracil (5-FU) and vinorelbine (VIN) to dipalmitoylphosphatidylcholine (DPPC) liposomes was estimated using UV-vis spectroscopy. The phase transition temperature was determined by the differential scanning calorimetry (DSC). 5-FU incorporates in more extend to liposomes than VIN and affects phase transition temperature of phospholipide forming liposomal membrane. There is only a slight influence of VIN on the 5-FU encapsulation in liposome vesicle while 5-FU affects significantly the VIN content in the liposome vesicles. The binding sites of VIN and 5-FU in HSA determined by fluorescence quenching method were confirmed by computer simulation. [ABSTRACT FROM AUTHOR]