Michal Strankowski | Gdansk University of Technology (original) (raw)

Papers by Michal Strankowski

Research paper thumbnail of High-density polyethylene/EPDM rubber blend composites of boron compounds for neutron shielding application

Express Polymer Letters, 2022

Research paper thumbnail of DSC Study of Polyurethanes obtained from 4,4'-Bis(10-Hydroxydecaoxy)biphenyl

Journal of Thermal Analysis and Calorimetry, 2003

The melting and crystallization of a series of polyurethanes derived from poly(1,6-hexylene adipa... more The melting and crystallization of a series of polyurethanes derived from poly(1,6-hexylene adipate)diol (PHA), 4,4'-dicyclohexylomethane diisocyanate (HMDI) and 4,4'-bis(10-hydroxydecaoxy)biphenyl (BHDBP) as a chain extender were investigated by using DSC. Thermal properties of the polyurethanes were found to be strongly influenced by the hard segment content.

Research paper thumbnail of Synthesis Attempt and Structural Studies of Novel A2CeWO6 Double Perovskites (A2+ = Ba, Ca) in and outside of Ambient Conditions

Research paper thumbnail of Graphene Reinforced Phenolic Foams

Research paper thumbnail of Shape Memory Materials from Rubbers

Materials

Smart materials are much discussed in the current research scenario. The shape memory effect is o... more Smart materials are much discussed in the current research scenario. The shape memory effect is one of the most fascinating occurrences in smart materials, both in terms of the phenomenon and its applications. Many metal alloys and polymers exhibit the shape memory effect (SME). Shape memory properties of elastomers, such as rubbers, polyurethanes, and other elastomers, are discussed in depth in this paper. The theory, factors impacting, and key uses of SME elastomers are all covered in this article. SME has been observed in a variety of elastomers and composites. Shape fixity and recovery rate are normally analysed through thermomechanical cycle studies to understand the effectiveness of SMEs. Polymer properties such as chain length, and the inclusion of fillers, such as clays, nanoparticles, and second phase polymers, will have a direct influence on the shape memory effect. The article discusses these aspects in a simple and concise manner.

Research paper thumbnail of Effect of Antioxidants on the Stability of Pitch-Based Polymer to Thermo-Oxidative Action

Chemistry & Chemical Technology

The influence of stabilizers-hydrogen donors-on the processes of thermooxidative destruction of p... more The influence of stabilizers-hydrogen donors-on the processes of thermooxidative destruction of pitch-based polymer has been investigated. It is shown that Irganox has not stabilizing effect on pitch-based polymer and melamine slightly retards the destructive process. A mixture of melamine and Irganox exhibits synergetic stabilizing effect and at the optimum ratio it can be used to prevent unwanted thermooxidative processes during pitch-based polymer preparation.

Research paper thumbnail of Rigid Polyurethane Foams Modified with Ground Tire Rubber - Mechanical, Morphological and Thermal Studies

Cellular Polymers

ABSTRACT Rigid polyurethane foams, prepared by a single step method, were modified with the two t... more ABSTRACT Rigid polyurethane foams, prepared by a single step method, were modified with the two types of ground tyre rubber particles, i.e. untreated and thermomechanically reclaimed using a co-rotating twin screw extruder. The foaming process as well as the structure and the physical, mechanical and thermal properties of the resulting foams were investigated. The presence of ground tyre rubber decreased the rate of polymerisation. The incorporation of ground tyre rubber decreased the total crosslink density of the produced material, as confirmed by a decrease in glass transition temperature measured by dynamic mechanical analysis and differential scanning calorimetry. The temperatures associated with a 10% and 50% mass loss of foam, determined by thermogravimetric analysis, increased due to the addition of ground tyre rubber particles.

Research paper thumbnail of Effect of Variation of Hard Segment Content and Graphene-Based Nanofiller Concentration on Morphological, Thermal, and Mechanical Properties of Polyurethane Nanocomposites

International Journal of Polymer Science

This study describes the development of a new class of high-performance polyurethane elastomer na... more This study describes the development of a new class of high-performance polyurethane elastomer nanocomposites containing reduced graphene oxide (RGO) or graphene nanoplatelets (GNP). Two types of polyurethane elastomers with different contents of hard segments (HS) were used as a polymer matrix. The developed nanocomposites were characterized by thermal analysis (DSC, TG), dynamic mechanical testing (DMA), hardness testing, mechanical properties, rheology, FTIR spectroscopy, XRD, and microscopy investigation (TEM, SEM). Morphological investigation confirmed better compatibility of RGO with the polyurethane (PU) matrix compared to GNP. Both applied nanofillers influenced melting and crystallization of the PU matrix. The nonlinear viscoelastic behavior of the nanocomposites (Payne effect) was studied, and the results were compared with theoretical predictions.

Research paper thumbnail of The mechanical properties and conduction of solid polyurethane electrolytes depending on the methods of synthesis and LiClO4 content as addition

Research paper thumbnail of Shape Memory Polyurethane Materials Containing Ferromagnetic Iron Oxide and Graphene Nanoplatelets

Materials

Intelligent materials, such as memory shape polymers, have attracted considerable attention due t... more Intelligent materials, such as memory shape polymers, have attracted considerable attention due to wide range of possible applications. Currently, intensive research is underway, in matters of obtaining memory shape materials that can be actuated via inductive methods, for example with help of magnetic field. In this work, an attempt was made to develop a new polymer composite-polyurethane modified with graphene nanoplates and ferromagnetic iron oxides-with improved mechanical properties and introduced magnetic and memory shape properties. Based on the conducted literature review, gathered data were compared to the results of similar materials. Obtained materials were tested for their thermal, rheological, mechanical and shape memory properties. Structure of both fillers and composites were also analyzed using various spectroscopic methods. The addition of fillers to the polyurethane matrix improved the mechanical and shape memory properties, without having a noticeable impact on thermal properties. As it was expected, the high content of fillers caused a significant change in viscosity of filled prepolymers (during the synthesis stage). Each of the studied composites showed better mechanical properties than the unmodified polyurethanes. The addition of magnetic particles introduced additional properties to the composite, which could significantly expand the functionality of the materials developed in this work.

Research paper thumbnail of Thermal and Mechanical Properties of Microporous Polyurethanes Modified with Reduced Graphene Oxide

International Journal of Polymer Science, 2016

Microporous polyurethanes (MPU) were modified by adding 0.25%–1.25 wt% of reduced graphene oxide ... more Microporous polyurethanes (MPU) were modified by adding 0.25%–1.25 wt% of reduced graphene oxide (RGO). The materials were prepared without solvent viain situpolymerization. From a technological point of view, it is very important to obtain functional materials by using reacting compounds only. The thermal characteristics of obtained MPU were investigated using TGA, DSC, and DMA techniques. In comparison to nonmodified microporous polyurethane, the thermal stability and mechanical properties of the modified systems have significantly improved. The temperature corresponding to the maximum degradation rate (Tmax) for nanocomposites containing 1% and 1.25 wt% of RGO was 51°C higher than that observed for pure microporous PU system. The increase of tensile strength was also observed for matrix with the addition of 0.5 wt% RGO nanofiller.

Research paper thumbnail of Polyurethane Nanocomposites Containing Reduced Graphene Oxide, FTIR, Raman, and XRD Studies

Journal of Spectroscopy, 2016

Recently, graphene and other graphene-based materials have become an essential part of composite ... more Recently, graphene and other graphene-based materials have become an essential part of composite science and technology. Their unique properties are not only restricted to graphene but also shared with derivative compounds like graphene oxide, reduced graphene oxide, functionalized graphene, and so forth. One of the most structurally important materials, graphene oxide (GO), is prepared by the oxidation of graphite. Though removal of the oxide groups can create vacancies and structural defects, reduced graphene oxide (rGO) is used in composites as effective filler similar to GO. Authors developed a new polyurethane nanocomposite using a derivative of grapheme, thermally reduced graphene oxide (rGO), to modify the matrix of polyurethane elastomers, by rGO.

Research paper thumbnail of Rigid Polyurethane Foams Modified With Ground Tire Rubber - Mechanical, Morphological and Thermal Studies

Cellular Polymers

Rigid polyurethane foams, prepared by a single step method, were modified with the two types of g... more Rigid polyurethane foams, prepared by a single step method, were modified with the two types of ground tyre rubber particles, i.e. untreated and thermomechanically reclaimed using a co-rotating twin screw extruder. The foaming process as well as the structure and the physical, mechanical and thermal properties of the resulting foams were investigated. The presence of ground tyre rubber decreased the rate of polymerisation. The incorporation of ground tyre rubber decreased the total crosslink density of the produced material, as confirmed by a decrease in glass transition temperature measured by dynamic mechanical analysis and differential scanning calorimetry. The temperatures associated with a 10% and 50% mass loss of foam, determined by thermogravimetric analysis, increased due to the addition of ground tyre rubber particles.

Research paper thumbnail of Effect of halogen-free flame retardants on morphology, mechanical and thermal properties of flexible polyurethane foams synthesized from polyglycerol

Przemysl Chemiczny

Flexible polyglycerol-contg. polyurethane foams were prepd. by a one-step method in a two-compone... more Flexible polyglycerol-contg. polyurethane foams were prepd. by a one-step method in a two-component system. Foams were modified by addn. of expanded graphite, optionally together with a com. halogen-free P flame retardant. Mech. properties, morphology, thermal properties and flammability of the foams were detd. The foams were classified as V0 materials according to UL 94 vertical burning test. The modification with expanded graphite resulted in an increase in the compressive strength (2.5 times), tensile strength (by 31%) and the temp. of 2% mass loss of the foam.

Research paper thumbnail of Thermoplastic polyurethane/(organically modified montmorillonite) nanocomposites produced by in situ polymerization

Express Polymer Letters, 2012

A series of polyurethane nanocomposites were synthesized from thermoplastic polyurethanes (with d... more A series of polyurethane nanocomposites were synthesized from thermoplastic polyurethanes (with different hard segment ratios) and two types of organically modified montmorillonites (OMMT)-Cloisite ® 10A and Cloisite ® 20A. The thermal behavior was examined by non-isothermal thermogravimetry (TG, DTG), Differential Scanning Calorimetry (DSC) and Dynamic-Mechanical Thermal Analysis (DMTA). The results of X-ray analyses showed that the OMMT produced the intercalated polyurethane nanocomposites. It has been proven that the thermal stability and tensile properties of these new systems were higher when the organoclay was present within the polymer matrix. Moreover, these properties depend on both the OMMT loading and the type of gallery cations of the organically modified montmorillonites.

Research paper thumbnail of Nonlinear Viscoelasticity in Three Dimensional Filler Reinforced Rubber Composites and Nanocomposites

Advances in Polymer Science, 2014

This chapter describes the influence of three-dimensional nanofillers used in elastomers on the n... more This chapter describes the influence of three-dimensional nanofillers used in elastomers on the nonlinear viscoelastic properties. In particular, this part focuses and investigates the most important three-dimensional nanoparticles, which are used to produce rubber nanocomposites. The rheological and the dynamic mechanical properties of elastomeric polymers, reinforced with spherical nanoparticles, like POSS, titanium dioxide and nanosilica, were described. These (3D) nanofillers in are used polymeric matrices, to create new, improved rubber nanocomposites, and these affect many of the system’s parameters (mechanical, chemical, physical) in comparison with conventional composites. The distribution of the nanosized fillers and interaction between nanofiller-nanofiller and nanofiller-matrix, in nanocomposite systems, is crucial for understanding their behavior under dynamic-mechanical conditions.

Research paper thumbnail of Polyurethane/ground tire rubber composite foams based on polyglycerol: Processing, mechanical and thermal properties

Journal of Reinforced Plastics and Composites, 2015

During the synthesis of rigid polyurethane foams, petrochemical polyol was substituted with polyg... more During the synthesis of rigid polyurethane foams, petrochemical polyol was substituted with polyglycerol, the product of thermo-catalytic polycondensation of waste glycerol, resulting from biodiesel production. Two types of ground tire rubbers, untreated and thermo-mechanically reclaimed, were used to obtain “green” polyurethane-polyglycerol composite foams. Samples were prepared by a single-step method for the ratio of NCO/OH groups equal to 2. Foams containing different types of fillers showed noticeably various appearances, which suggested significant differences in the matrix–filler interactions between materials modified with untreated and reclaimed ground tire rubber. Addition of rubber particles shortened the processing time by more than 20 s and reduced the temperature during synthesis. Incorporation of ground tire rubber increased the size of the cells in comparison to unmodified foam. Modifications of rigid polyurethane foams resulted in the increase of apparent density an...

Research paper thumbnail of Rigid polyurethane foams from a polyglycerol-based polyol

European Polymer Journal, 2014

Research paper thumbnail of Evaluation of the photoprotective effect of β-cyclodextrin on the emission of volatile degradation products of ranitidine

Journal of pharmaceutical and biomedical analysis, 2014

The process of the photo-excitation of ranitidine hydrochloride (RAN) in a solid state makes visi... more The process of the photo-excitation of ranitidine hydrochloride (RAN) in a solid state makes visible changes to its colour and generates an unpleasant odour. The purpose of the present study was to observe the protective effects of β-cyclodextrin (CD) complexation as well as the effect of the mixture of two stoichiometries 1:1 and 1:2 (RAN:CD, IC) on the photostability of samples in a solid state. Samples of inclusion complexes (IC) and physical mixtures (PM) were prepared and irradiated for 48h in a Suntest CPS+ chamber. Irradiated samples were analyzed using nuclear magnetic resonance ((1)H NMR), infrared spectroscopy (FT-IR), the differential scanning calorimetry method (DSC) and thermogravimetry analysis (TGA). Volatiles were monitored with the use of headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS). The protective effect of CD was noticed with respect to IC, and also PM. Achieved photostabilization of complexed RAN against photodegradat...

Research paper thumbnail of Evaluation of the photoprotective effect of β-cyclodextrin on the emission of volatile degradation products of ranitidine

The process of the photo-excitation of ranitidine hydrochloride (RAN) in a solid state makes visi... more The process of the photo-excitation of ranitidine hydrochloride (RAN) in a solid state makes visible changes to its colour and generates an unpleasant odour. The purpose of the present study was to observe the protective effects of β-cyclodextrin (CD) complexation as well as the effect of the mixture of two stoichiometries 1:1 and 1:2 (RAN:CD, IC) on the photostability of samples in a solid state. Samples of inclusion complexes (IC) and physical mixtures (PM) were prepared and irradiated for 48h in a Suntest CPS+ chamber. Irradiated samples were analyzed using nuclear magnetic resonance ((1)H NMR), infrared spectroscopy (FT-IR), the differential scanning calorimetry method (DSC) and thermogravimetry analysis (TGA). Volatiles were monitored with the use of headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS). The protective effect of CD was noticed with respect to IC, and also PM. Achieved photostabilization of complexed RAN against photodegradation could be explained due to either the inclusion of the furan part of RAN into the CD cavity as shown by the (1)H NMR ROESY (rotation frame nuclear Overhauser effect spectroscopy) spectrum or the screening effect of CD. FT-IR spectra, DSC curves and microscope images of irradiated samples of protected RAN did not indicate any physical changes, such as phase transfer.

Research paper thumbnail of High-density polyethylene/EPDM rubber blend composites of boron compounds for neutron shielding application

Express Polymer Letters, 2022

Research paper thumbnail of DSC Study of Polyurethanes obtained from 4,4'-Bis(10-Hydroxydecaoxy)biphenyl

Journal of Thermal Analysis and Calorimetry, 2003

The melting and crystallization of a series of polyurethanes derived from poly(1,6-hexylene adipa... more The melting and crystallization of a series of polyurethanes derived from poly(1,6-hexylene adipate)diol (PHA), 4,4'-dicyclohexylomethane diisocyanate (HMDI) and 4,4'-bis(10-hydroxydecaoxy)biphenyl (BHDBP) as a chain extender were investigated by using DSC. Thermal properties of the polyurethanes were found to be strongly influenced by the hard segment content.

Research paper thumbnail of Synthesis Attempt and Structural Studies of Novel A2CeWO6 Double Perovskites (A2+ = Ba, Ca) in and outside of Ambient Conditions

Research paper thumbnail of Graphene Reinforced Phenolic Foams

Research paper thumbnail of Shape Memory Materials from Rubbers

Materials

Smart materials are much discussed in the current research scenario. The shape memory effect is o... more Smart materials are much discussed in the current research scenario. The shape memory effect is one of the most fascinating occurrences in smart materials, both in terms of the phenomenon and its applications. Many metal alloys and polymers exhibit the shape memory effect (SME). Shape memory properties of elastomers, such as rubbers, polyurethanes, and other elastomers, are discussed in depth in this paper. The theory, factors impacting, and key uses of SME elastomers are all covered in this article. SME has been observed in a variety of elastomers and composites. Shape fixity and recovery rate are normally analysed through thermomechanical cycle studies to understand the effectiveness of SMEs. Polymer properties such as chain length, and the inclusion of fillers, such as clays, nanoparticles, and second phase polymers, will have a direct influence on the shape memory effect. The article discusses these aspects in a simple and concise manner.

Research paper thumbnail of Effect of Antioxidants on the Stability of Pitch-Based Polymer to Thermo-Oxidative Action

Chemistry & Chemical Technology

The influence of stabilizers-hydrogen donors-on the processes of thermooxidative destruction of p... more The influence of stabilizers-hydrogen donors-on the processes of thermooxidative destruction of pitch-based polymer has been investigated. It is shown that Irganox has not stabilizing effect on pitch-based polymer and melamine slightly retards the destructive process. A mixture of melamine and Irganox exhibits synergetic stabilizing effect and at the optimum ratio it can be used to prevent unwanted thermooxidative processes during pitch-based polymer preparation.

Research paper thumbnail of Rigid Polyurethane Foams Modified with Ground Tire Rubber - Mechanical, Morphological and Thermal Studies

Cellular Polymers

ABSTRACT Rigid polyurethane foams, prepared by a single step method, were modified with the two t... more ABSTRACT Rigid polyurethane foams, prepared by a single step method, were modified with the two types of ground tyre rubber particles, i.e. untreated and thermomechanically reclaimed using a co-rotating twin screw extruder. The foaming process as well as the structure and the physical, mechanical and thermal properties of the resulting foams were investigated. The presence of ground tyre rubber decreased the rate of polymerisation. The incorporation of ground tyre rubber decreased the total crosslink density of the produced material, as confirmed by a decrease in glass transition temperature measured by dynamic mechanical analysis and differential scanning calorimetry. The temperatures associated with a 10% and 50% mass loss of foam, determined by thermogravimetric analysis, increased due to the addition of ground tyre rubber particles.

Research paper thumbnail of Effect of Variation of Hard Segment Content and Graphene-Based Nanofiller Concentration on Morphological, Thermal, and Mechanical Properties of Polyurethane Nanocomposites

International Journal of Polymer Science

This study describes the development of a new class of high-performance polyurethane elastomer na... more This study describes the development of a new class of high-performance polyurethane elastomer nanocomposites containing reduced graphene oxide (RGO) or graphene nanoplatelets (GNP). Two types of polyurethane elastomers with different contents of hard segments (HS) were used as a polymer matrix. The developed nanocomposites were characterized by thermal analysis (DSC, TG), dynamic mechanical testing (DMA), hardness testing, mechanical properties, rheology, FTIR spectroscopy, XRD, and microscopy investigation (TEM, SEM). Morphological investigation confirmed better compatibility of RGO with the polyurethane (PU) matrix compared to GNP. Both applied nanofillers influenced melting and crystallization of the PU matrix. The nonlinear viscoelastic behavior of the nanocomposites (Payne effect) was studied, and the results were compared with theoretical predictions.

Research paper thumbnail of The mechanical properties and conduction of solid polyurethane electrolytes depending on the methods of synthesis and LiClO4 content as addition

Research paper thumbnail of Shape Memory Polyurethane Materials Containing Ferromagnetic Iron Oxide and Graphene Nanoplatelets

Materials

Intelligent materials, such as memory shape polymers, have attracted considerable attention due t... more Intelligent materials, such as memory shape polymers, have attracted considerable attention due to wide range of possible applications. Currently, intensive research is underway, in matters of obtaining memory shape materials that can be actuated via inductive methods, for example with help of magnetic field. In this work, an attempt was made to develop a new polymer composite-polyurethane modified with graphene nanoplates and ferromagnetic iron oxides-with improved mechanical properties and introduced magnetic and memory shape properties. Based on the conducted literature review, gathered data were compared to the results of similar materials. Obtained materials were tested for their thermal, rheological, mechanical and shape memory properties. Structure of both fillers and composites were also analyzed using various spectroscopic methods. The addition of fillers to the polyurethane matrix improved the mechanical and shape memory properties, without having a noticeable impact on thermal properties. As it was expected, the high content of fillers caused a significant change in viscosity of filled prepolymers (during the synthesis stage). Each of the studied composites showed better mechanical properties than the unmodified polyurethanes. The addition of magnetic particles introduced additional properties to the composite, which could significantly expand the functionality of the materials developed in this work.

Research paper thumbnail of Thermal and Mechanical Properties of Microporous Polyurethanes Modified with Reduced Graphene Oxide

International Journal of Polymer Science, 2016

Microporous polyurethanes (MPU) were modified by adding 0.25%–1.25 wt% of reduced graphene oxide ... more Microporous polyurethanes (MPU) were modified by adding 0.25%–1.25 wt% of reduced graphene oxide (RGO). The materials were prepared without solvent viain situpolymerization. From a technological point of view, it is very important to obtain functional materials by using reacting compounds only. The thermal characteristics of obtained MPU were investigated using TGA, DSC, and DMA techniques. In comparison to nonmodified microporous polyurethane, the thermal stability and mechanical properties of the modified systems have significantly improved. The temperature corresponding to the maximum degradation rate (Tmax) for nanocomposites containing 1% and 1.25 wt% of RGO was 51°C higher than that observed for pure microporous PU system. The increase of tensile strength was also observed for matrix with the addition of 0.5 wt% RGO nanofiller.

Research paper thumbnail of Polyurethane Nanocomposites Containing Reduced Graphene Oxide, FTIR, Raman, and XRD Studies

Journal of Spectroscopy, 2016

Recently, graphene and other graphene-based materials have become an essential part of composite ... more Recently, graphene and other graphene-based materials have become an essential part of composite science and technology. Their unique properties are not only restricted to graphene but also shared with derivative compounds like graphene oxide, reduced graphene oxide, functionalized graphene, and so forth. One of the most structurally important materials, graphene oxide (GO), is prepared by the oxidation of graphite. Though removal of the oxide groups can create vacancies and structural defects, reduced graphene oxide (rGO) is used in composites as effective filler similar to GO. Authors developed a new polyurethane nanocomposite using a derivative of grapheme, thermally reduced graphene oxide (rGO), to modify the matrix of polyurethane elastomers, by rGO.

Research paper thumbnail of Rigid Polyurethane Foams Modified With Ground Tire Rubber - Mechanical, Morphological and Thermal Studies

Cellular Polymers

Rigid polyurethane foams, prepared by a single step method, were modified with the two types of g... more Rigid polyurethane foams, prepared by a single step method, were modified with the two types of ground tyre rubber particles, i.e. untreated and thermomechanically reclaimed using a co-rotating twin screw extruder. The foaming process as well as the structure and the physical, mechanical and thermal properties of the resulting foams were investigated. The presence of ground tyre rubber decreased the rate of polymerisation. The incorporation of ground tyre rubber decreased the total crosslink density of the produced material, as confirmed by a decrease in glass transition temperature measured by dynamic mechanical analysis and differential scanning calorimetry. The temperatures associated with a 10% and 50% mass loss of foam, determined by thermogravimetric analysis, increased due to the addition of ground tyre rubber particles.

Research paper thumbnail of Effect of halogen-free flame retardants on morphology, mechanical and thermal properties of flexible polyurethane foams synthesized from polyglycerol

Przemysl Chemiczny

Flexible polyglycerol-contg. polyurethane foams were prepd. by a one-step method in a two-compone... more Flexible polyglycerol-contg. polyurethane foams were prepd. by a one-step method in a two-component system. Foams were modified by addn. of expanded graphite, optionally together with a com. halogen-free P flame retardant. Mech. properties, morphology, thermal properties and flammability of the foams were detd. The foams were classified as V0 materials according to UL 94 vertical burning test. The modification with expanded graphite resulted in an increase in the compressive strength (2.5 times), tensile strength (by 31%) and the temp. of 2% mass loss of the foam.

Research paper thumbnail of Thermoplastic polyurethane/(organically modified montmorillonite) nanocomposites produced by in situ polymerization

Express Polymer Letters, 2012

A series of polyurethane nanocomposites were synthesized from thermoplastic polyurethanes (with d... more A series of polyurethane nanocomposites were synthesized from thermoplastic polyurethanes (with different hard segment ratios) and two types of organically modified montmorillonites (OMMT)-Cloisite ® 10A and Cloisite ® 20A. The thermal behavior was examined by non-isothermal thermogravimetry (TG, DTG), Differential Scanning Calorimetry (DSC) and Dynamic-Mechanical Thermal Analysis (DMTA). The results of X-ray analyses showed that the OMMT produced the intercalated polyurethane nanocomposites. It has been proven that the thermal stability and tensile properties of these new systems were higher when the organoclay was present within the polymer matrix. Moreover, these properties depend on both the OMMT loading and the type of gallery cations of the organically modified montmorillonites.

Research paper thumbnail of Nonlinear Viscoelasticity in Three Dimensional Filler Reinforced Rubber Composites and Nanocomposites

Advances in Polymer Science, 2014

This chapter describes the influence of three-dimensional nanofillers used in elastomers on the n... more This chapter describes the influence of three-dimensional nanofillers used in elastomers on the nonlinear viscoelastic properties. In particular, this part focuses and investigates the most important three-dimensional nanoparticles, which are used to produce rubber nanocomposites. The rheological and the dynamic mechanical properties of elastomeric polymers, reinforced with spherical nanoparticles, like POSS, titanium dioxide and nanosilica, were described. These (3D) nanofillers in are used polymeric matrices, to create new, improved rubber nanocomposites, and these affect many of the system’s parameters (mechanical, chemical, physical) in comparison with conventional composites. The distribution of the nanosized fillers and interaction between nanofiller-nanofiller and nanofiller-matrix, in nanocomposite systems, is crucial for understanding their behavior under dynamic-mechanical conditions.

Research paper thumbnail of Polyurethane/ground tire rubber composite foams based on polyglycerol: Processing, mechanical and thermal properties

Journal of Reinforced Plastics and Composites, 2015

During the synthesis of rigid polyurethane foams, petrochemical polyol was substituted with polyg... more During the synthesis of rigid polyurethane foams, petrochemical polyol was substituted with polyglycerol, the product of thermo-catalytic polycondensation of waste glycerol, resulting from biodiesel production. Two types of ground tire rubbers, untreated and thermo-mechanically reclaimed, were used to obtain “green” polyurethane-polyglycerol composite foams. Samples were prepared by a single-step method for the ratio of NCO/OH groups equal to 2. Foams containing different types of fillers showed noticeably various appearances, which suggested significant differences in the matrix–filler interactions between materials modified with untreated and reclaimed ground tire rubber. Addition of rubber particles shortened the processing time by more than 20 s and reduced the temperature during synthesis. Incorporation of ground tire rubber increased the size of the cells in comparison to unmodified foam. Modifications of rigid polyurethane foams resulted in the increase of apparent density an...

Research paper thumbnail of Rigid polyurethane foams from a polyglycerol-based polyol

European Polymer Journal, 2014

Research paper thumbnail of Evaluation of the photoprotective effect of β-cyclodextrin on the emission of volatile degradation products of ranitidine

Journal of pharmaceutical and biomedical analysis, 2014

The process of the photo-excitation of ranitidine hydrochloride (RAN) in a solid state makes visi... more The process of the photo-excitation of ranitidine hydrochloride (RAN) in a solid state makes visible changes to its colour and generates an unpleasant odour. The purpose of the present study was to observe the protective effects of β-cyclodextrin (CD) complexation as well as the effect of the mixture of two stoichiometries 1:1 and 1:2 (RAN:CD, IC) on the photostability of samples in a solid state. Samples of inclusion complexes (IC) and physical mixtures (PM) were prepared and irradiated for 48h in a Suntest CPS+ chamber. Irradiated samples were analyzed using nuclear magnetic resonance ((1)H NMR), infrared spectroscopy (FT-IR), the differential scanning calorimetry method (DSC) and thermogravimetry analysis (TGA). Volatiles were monitored with the use of headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS). The protective effect of CD was noticed with respect to IC, and also PM. Achieved photostabilization of complexed RAN against photodegradat...

Research paper thumbnail of Evaluation of the photoprotective effect of β-cyclodextrin on the emission of volatile degradation products of ranitidine

The process of the photo-excitation of ranitidine hydrochloride (RAN) in a solid state makes visi... more The process of the photo-excitation of ranitidine hydrochloride (RAN) in a solid state makes visible changes to its colour and generates an unpleasant odour. The purpose of the present study was to observe the protective effects of β-cyclodextrin (CD) complexation as well as the effect of the mixture of two stoichiometries 1:1 and 1:2 (RAN:CD, IC) on the photostability of samples in a solid state. Samples of inclusion complexes (IC) and physical mixtures (PM) were prepared and irradiated for 48h in a Suntest CPS+ chamber. Irradiated samples were analyzed using nuclear magnetic resonance ((1)H NMR), infrared spectroscopy (FT-IR), the differential scanning calorimetry method (DSC) and thermogravimetry analysis (TGA). Volatiles were monitored with the use of headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS). The protective effect of CD was noticed with respect to IC, and also PM. Achieved photostabilization of complexed RAN against photodegradation could be explained due to either the inclusion of the furan part of RAN into the CD cavity as shown by the (1)H NMR ROESY (rotation frame nuclear Overhauser effect spectroscopy) spectrum or the screening effect of CD. FT-IR spectra, DSC curves and microscope images of irradiated samples of protected RAN did not indicate any physical changes, such as phase transfer.