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Poly(3-hydroxybutyrate) is a biopolymer which is used to production of implants in the human body. On the other hand, the physical and mechanical properties of poly(3-hydroxybutyrate) are compared to the properties of isotactic polypropylene what makes poly(3-hydroxybutyrate) possible substitute for polypropylene. Unfortunately, the melting point of poly(3-hydroxybutyrate) is almost equal to its degradation temperature what gives very narrow window of its processing conditions. Therefore, numerous attempts are being made to improve the poly(3-hydroxybutyrate) properties. In the present work, hybrid nanobiocomposites based on poly(3-hydroxybutyrate) as a matrix with the use of organic nanoclay - Cloisite 30B and linear polyurethane as a second filler have been manufactured. The linear polyurethane was based on diphenylmethane 4,4'-diisocyanate and diol with imidazoquinazoline rings. The obtained nanobiocomposites were characterized by X-ray diffraction, scanning and transmission electron microscopies, thermogravimetry, differential scanning calorimetry and their selected mechanical properties were tested. The resulting hybrid nanobiocomposites have intercalated/exfoliated structure. The nanobiocomposites characterize a higher thermal stability and a wider range of processing temperatures compared to the unfilled matrix. The plasticizing influence of nanofillers was also observed. In addition, the mechanical properties of the discussed nanobiocomposites were examined and compared with those ones of the unfilled poly(3-hydroxybutyrate). The new-obtained nanobiocomposites based on poly(3-hydroxybutyrate) containing 1% Cloisite 30B and 5% by mass of the linear of polyurethane characterized the highest improvement of processing conditions. They have the biggest difference between the temperature of degradation and the onset melting temperature, about 100°C. [ABSTRACT FROM AUTHOR]

In this work, research concerning the synthesis and properties of linear polyurethanes (PUs) with the imidazoquinazoline rings was represented. Reaction conditions of 2,6-bis(2-hydroxyethyl)-1-phenylimida-zo[1,5-c]quinazoline-3,5-dione (BHPIQ) with 1,6-hexamethylene diisocyanate were determined and optimized. These conditions are adapted to reaction of BHPIQ with 4,4′-diphenylmethane diisocyanate and 2,4-toluene diisocyanate. New PUs with imidazoquinazoline rings were characterized by spectral methods (1H-NMR and IR spectroscopies), which confirm their structures. Their molar masses and dispersity index were measured by size exclusion chromatography method. The wide-angle X-ray scattering and differential scanning calorimetry (DSC) studies have shown that all PUs based on BHPIQ are amorphous. Moreover, thermal properties of PUs were investigated by thermogravimetry analysis, standard DSC, and temperature-modulated DSC methods. During thermogravimetric measurements, the exhaust gases were analyzed by FTIR method. Incorporation of imidazoquinazoline ring into the PU chains escalates their glass transition temperature; thus, their heat resistance was enhanced. Furthermore, their degradation rate and the amount of released degradation products were reduced. The investigated properties of the obtained PUs with imidazoquinazoline rings were compared with those ones of suitable PUs based on 1,4-butanediol. Linear polyurethanes were obtained in reaction of 1-phenyl-2,6-bis(2-hydroxyethylimidazo[1,5-c]quinazoline-3,5-dione with hexamethylene 1,6-diisocyanate, 4,4′-diphenylmethane diisocyanate and toluene 2,4-diisocyanate. Their composition and structure were confirmed. The phase contents and thermal properties were investigated [ABSTRACT FROM AUTHOR]

The synthesis of polyurethane coatings by polyaddition in bulk using polyesterols and polyetherols with variable polarity was successfully carried out. IR and NMR spectra confirmed the structure of obtained polyurethanes and the incorporation of a polydimethylsiloxane(PDMS) modifier into the polyurethane structure. The differential scanning calorimetry and IR spectroscopy were employed for the microstructural assessment of the obtained materials. It was noted that crucial effect on free surface energy of the coatings has polyol structure as well as ratio of hard to soft segments. The contact angle measurements indicated that with increasing content of the polysiloxane in the flexible PTMO segments, the hydrophobicity significantly increased. It was demonstrated that hydrophobicity and mechanical strength, which are important for applications as biomaterials, are adversative in significant extent. The resulting coatings were characterized in terms of the heat resistance and changes during incubation in a Baxter saline solution. [ABSTRACT FROM AUTHOR]

In this work series of high-solids crosslinked hybrid networks based on the comb-like structure fluorinated epoxyfunctional siloxane modified with the epoxy-terminated urethane oligomer and cured with diethylenetriamine, were obtained. The structure of the obtained poly(urethane-siloxane) thermosets was confirmed by FTIR spectroscopy. The thermal properties of the samples were investigated by DSC and TG analyses. The coupled TG-FTIR-MS technique for analysis of gases evolved during thermal decomposition of hybrid materials, was employed. The water contact angles, water absorption and some performance properties of the obtained hybrid coatings were also investigated. The synthesized poly(urethane-siloxane) networks are basically hydrophobic materials. An increased amount of epoxyurethane resulted in a decrease of glass transition temperature, Persoz hardness, and thermal stability as well as in increase of water absorption. [ABSTRACT FROM AUTHOR]

Elastomeric polyurethane films containing HDI or IPDI diisocyanate, poly(caprolactone) diol and butane-1,4-diol (BD) or gastrodin (GS) were synthesized in two-step polyaddition reaction. Their chemical structures were confirmed by FTIR and NMR spectroscopy. The phase structure was analyzed by WAXD and DSC methods, confirming the presence of a crystalline phase in the hard domains. The introduction of GS instead of BD results in an increase in the free surface energy of the films (FSE > 40 mJ/m2). The consequence of this is an increase in the water uptake, but at the same time a reduction in resistance to hydrolysis in Baxter's salt solution, as well as increased biodegradability in contact with bacterial strains (Bacillus sp. - gram positive, Pseudomonas sp. - gram negative). PU elastomeric films modified by gastrodin can be applied in tissue engineering films as temporary biomaterials with hydrophilic properties, capable of biodegradation in the body. [Display omitted] • Using the gastrodin used in natural medicine, new elastomere polyurethane films were synthesized. • Their surface and hydrolytic properties as well bacterial resistance as new potential biomaterials were assessed. • Gastrodin, which is a multifunctional hydroxyl reagent, enabled the effective extension of the linear isocyanate prepolymer. [ABSTRACT FROM AUTHOR]

In this work, a series of high-solids crosslinked hybrid networks based on the epoxy-terminated urethane oligomer and the comb-like structure epoxy-functional siloxane cured with diethylenetriamine, were obtained. The structure of the obtained poly(urethane-siloxane) thermosets was confirmed by FTIR spectroscopy. The samples were submitted to detailed thermal degradation investigations at non-isothermal conditions in nitrogen and air. The contact angles of the coatings and free surface energy calculated by Owens-Wend as well as van Oss-Good method, were studied. Some coating properties of the obtained hybrid materials were also investigated. The synthesized poly(urethane-siloxane) networks are hydrophobic materials, with free surface energy of 26-29 mJ/m. The thermal stability and hardness of these increases with increasing siloxane content. [ABSTRACT FROM AUTHOR]

Highlights • Binary and ternary lanthanide complexes with N -phenylanthranilic acid and 1,10-phenanthroline were synthesized. • Formation of the complexes was confirmed by FTIR and XRD methods. • Previously unreported thermal behaviour of these compounds was investigated in oxidative and inert atmospheres. • The coupled TG-FITR-MS technique provided information about gaseous products of thermal decomposition. • The antibacterial activity of the obtained compounds were proved. Abstract New binuclear binary and ternary complexes of Sm(III), Eu(III), and Gd(III) ions with N -phenylanthranilic acid and 1,10-phenanthroline were obtained in solid phase and characterized by chemical and elemental analysis, molar conductance, UV–vis and IR spectroscopies as well as thermoanalytical techniques (TG/DTG–DSC coupled with MS and FT-IR). The dilution method was used to examine the antibacterial activity of the synthesized compounds. The spectroscopic studies indicated that the carboxylate group of N -phenylantranilate ligand is involved in the coordination of metal ion both in binary and ternary complexes. Thermal decomposition of the obtained compounds was carried out in air and nitrogen atmosphere. During heating the complexes decompose via intermediate products to the oxide (Ln 2 O 3) in air atmosphere and to the oxide (Ln 2 O 3) or oxide polluted by carbon (Ln 2 O 3 +nC) in nitrogen atmosphere. The dehydration process was discussed in relation to the nature of water present in these compounds. Using coupled TG-FTIR-MS techniques the decomposition pathways of the synthesized compounds were examined. Additionally, gaseous products released during pyrolysis and thermal oxidation of the complexes were identified. All the complexes exhibit marked activity against two Gram-negative (Escherichia coli and Pseudomonas aeruginosa) and one Gram-positive (Staphylococcus aureus) bacterial strains. The ternary complexes, especially Gd(III) complex in comparison with the binary ones, have enhanced activity against Escherichia coli. Moreover, antibacterial activity of the synthesized compounds with respect to Pseudomonas aeruginosa is comparable to tetracycline and greater than for kanamycin, erythromycin, and ampicillin. [ABSTRACT FROM AUTHOR]