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Cristea M.♦, Ionita D.♦, Oprea S.♦, Pieczyska E.A., How loading type affects viscoelastic response in polyurethane structures,
SolMech 2018, 41st SOLID MECHANICS CONFERENCE, 2018-08-27/08-31, Warszawa (PL), pp.342-343, 2018 |  |
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Golasiński K.M., Pieczyska E.A., Staszczak M., Cristea M.♦, Experimental investigation of thermomechanical properties of multifunctional materials at IPPT PAN,
MACRO Iasi, The XXVI-th Symposium PROGRESS IN ORGANIC AND POLYMER CHEMISTRY, 2017-10-05/10-06, Jassy (RO), pp.1-1, 2017 |  |
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Kukla D., Staszczak M., Pieczyska E.A., Heljak M.♦, Szlązak K.♦, Święszkowski W.♦, Cristea M.♦, Tobushi H.♦, Hayashi S.♦, Evaluation of the properties of polymeric foams with shape memory under load,
PCM-CMM 2015, 3rd Polish Congress of Mechanics and 21st Computer Methods in Mechanics, 2015-09-08/09-11, Gdańsk (PL), pp.143-144, 2015 Abstract: The paper presents the results of experimental investigation on polymer foam with shape memory properties. The research is focused on characterization of the microstructure of the foam and understanding the mechanisms of deformation under static and dynamic loading. Up till now, selected experimental techniques have been applied. Dynamic Mechanical Analysis (DMA) allows determining the extent of the value of the glass transition temperature under different load conditions, which also reveals the transformation temperature range for the SMP foam. Scanning electron microscopy (SEM) shows the foam microstructure in various scales, while X-ray tomography gave 3D microstructure results presenting in addition mechanism of the cells deformation and changes in their geometry under 30 % and 50% strain. BOSE system enables obtaining the results on dynamic loading. Keywords: Shape memory polymer foam, Dynamic mechanical analysis, Glass transition temperature, X-ray tomography Affiliations:
Kukla D. | - | IPPT PAN | Staszczak M. | - | IPPT PAN | Pieczyska E.A. | - | IPPT PAN | Heljak M. | - | Warsaw University of Technology (PL) | Szlązak K. | - | other affiliation | Święszkowski W. | - | other affiliation | Cristea M. | - | Petru Poni Institute of Macromolecular Chemistry (RO) | Tobushi H. | - | Aichi Institute of Technology (JP) | Hayashi S. | - | SMP Technologies Inc. (JP) |
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Staszczak M., Pieczyska E.A., Maj M., Kowalczyk-Gajewska K., Cristea M.♦, Tobushi H.♦, Hayashi S.♦, Shape memory polymer – shape fixity and recovery in cyclic loading,
PCM-CMM 2015, 3rd Polish Congress of Mechanics and 21st Computer Methods in Mechanics, 2015-09-08/09-11, Gdańsk (PL), pp.147-148, 2015 Abstract: The paper concerns investigation of polyurethane shape memory polymer (SMP) properties. Shape fixity and shape recovery, important parameters for the SMP applications, were quantitatively estimated in thermomechanical cyclic loading; three subsequent thermomechanical loading cycles were performed. It was observed that the shape fixity is proper and does not depend on the cycle number. The obtained mean values of shape fixity parameters are 97-98 %. Although the shape recovery is poor (=83 %) in the first cycle of the thermomechanical loading, it is excellent in the subsequent cycles (=99-100 %). The evaluated parameters confirm good shape memory properties of the SMP. Keywords: Shape memory polyurethane, shape fixity, shape recovery, thermomechanical loading, cyclic loading Affiliations:
Staszczak M. | - | IPPT PAN | Pieczyska E.A. | - | IPPT PAN | Maj M. | - | IPPT PAN | Kowalczyk-Gajewska K. | - | IPPT PAN | Cristea M. | - | Petru Poni Institute of Macromolecular Chemistry (RO) | Tobushi H. | - | Aichi Institute of Technology (JP) | Hayashi S. | - | SMP Technologies Inc. (JP) |
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Pieczyska E.A., Maj M., Kowalczyk-Gajewska K., Staszczak M., Tobushi H.♦, Hayashi S.♦, Cristea M.♦, Thermomechanical analysis of shape memory polymer under cyclic loading and relaxation conditions,
ICEM-16, 16th International Conference on Experimental Mechanics, 2014-07-07/07-11, Cambridge (GB), pp.1-2, 2014 Abstract: Experimental evaluation and modeling of a new polyurethane shape memory polymer (SMP) subjected to cyclic tension and stress-relaxation tests are presented. The influence of effects of thermomechanical couplings on the SMP thermomechanical behaviour for various strain rates was studied, basing on the sample temperature changes measured by a fast and sensitive infrared camera. The constitutive model valid in finite strain regime was developed following [5]. In the proposed approach SMP is described as a two-phase material composed of hyperelastic rubbery phase and elastic-viscoplastic glassy phase while the volume content of phases is specified by the current temperature. Keywords: Experimental evaluation, constitutive modeling, polyurethane shape memory polymer, cyclic tension, stress-relaxation tests, effects of thermomechanical couplings, thermomechanical behaviour, various strain rates, temperature changes, sensitive infrared camera, hyperelastic rubbery phase, elastic-viscoplastic glassy phase Affiliations:
Pieczyska E.A. | - | IPPT PAN | Maj M. | - | IPPT PAN | Kowalczyk-Gajewska K. | - | IPPT PAN | Staszczak M. | - | IPPT PAN | Tobushi H. | - | Aichi Institute of Technology (JP) | Hayashi S. | - | SMP Technologies Inc. (JP) | Cristea M. | - | Petru Poni Institute of Macromolecular Chemistry (RO) |
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Kowalczyk-Gajewska K., Pieczyska E.A., Maj M., Staszczak M., Majewski M., Cristea M.♦, Tobushi H.♦, Two-phase model of shape memory polymers at finite strains: formulation and experimental verification,
SolMech 2014, 39th Solid Mechanics Conference, 2014-09-01/09-05, Zakopane (PL), pp.259-260, 2014 Abstract: A constitutive model of SMP, formulated at large strain format, is developed. SMP is described as a two-phase material composed of a soft rubbery phase and a hard glassy phase. The volume fraction of each phase is postulated as a logistic function of temperature. Identification of model parameters has been performed using the experimental tensile loading-unloading tests with different strain rates conducted at thermal chamber at different temperatures.
Keywords: shape-memory polymers, two-phase model, large strain framework Affiliations:
Kowalczyk-Gajewska K. | - | IPPT PAN | Pieczyska E.A. | - | IPPT PAN | Maj M. | - | IPPT PAN | Staszczak M. | - | IPPT PAN | Majewski M. | - | IPPT PAN | Cristea M. | - | Petru Poni Institute of Macromolecular Chemistry (RO) | Tobushi H. | - | Aichi Institute of Technology (JP) |
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Staszczak M., Pieczyska E.A., Maj M., Kowalczyk-Gajewska K., Cristea M.♦, Tobushi H.♦, Hayashi S.♦, Estimation of shape fixity and shape recovery – crucial parameters for shape memory polymer applications,
SolMech 2014, 39th Solid Mechanics Conference, 2014-09-01/09-05, Zakopane (PL), pp.267-268, 2014 Abstract: Shape memory polymers (SMP) are new unique and attractive materials which demonstrate shape memory properties. It means that the materials, as a result of an external stimulus such as temperature, can recover their original (permanent) shape from deformed (temporary) shape. The mechanical characteristics of SMP, e.g. the elastic modulus and the yield stress, change significantly below and above their glass transition temperature Tg. It can be explained by differences of molecular motion of the polymer chains below and above Tg [1, 2]. Two phenomena due to this can be observed in the SMP. The first one is a shape fixity which means that it is possible to fix a temporary shape by cooling the deformed SMP below Tg. The second phenomenon, called a shape recovery, denotes the property that the original shape, changed due to deformation, is recovered during subsequent heating above the SMP Tg temperature. Preliminary estimation of these two parameters, crucial to assess SMP potential applications, is the subject of this paper [1]. Keywords: Shape memory polymers, elastic modulus, yield stress, glass transition temperature, shape fixity, shape recovery Affiliations:
Staszczak M. | - | IPPT PAN | Pieczyska E.A. | - | IPPT PAN | Maj M. | - | IPPT PAN | Kowalczyk-Gajewska K. | - | IPPT PAN | Cristea M. | - | Petru Poni Institute of Macromolecular Chemistry (RO) | Tobushi H. | - | Aichi Institute of Technology (JP) | Hayashi S. | - | SMP Technologies Inc. (JP) |
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Pieczyska E.A., Tobushi H.♦, Hayashi S.♦, Maj M., Kowalczyk-Gajewska K., Staszczak M., Cristea M.♦, Thermomechanical Analysis of Shape Memory Polyurethane,
4th Integrity, Reliability and Failure of Mechanical Systems, 2013-06-23/06-27, Funchal (PT), pp.1-2, 2013 Abstract: This paper presents experimental evaluation of a new polyurethane shape memory polymer (PU-SMP) produced by SMP Technologies Inc. It discusses mechanical characteristics and temperature changes of the SMP specimens subjected to tension test performed at room temperature with various strain rates. Basing on the mechanical data and the relevant temperature changes, we have studied the thermomechanical properties of the PU-SMP and influence of the strain rate on the strain localization behavior. Finally, we have identified the material parameters for the one-dimensional rheological model of the SMP.
Keywords: shape memory polyurethane, tension test, dynamic mechanical analysis, infrared camera, temperature change, thermomechanical properties, rheological model Affiliations:
Pieczyska E.A. | - | IPPT PAN | Tobushi H. | - | Aichi Institute of Technology (JP) | Hayashi S. | - | SMP Technologies Inc. (JP) | Maj M. | - | IPPT PAN | Kowalczyk-Gajewska K. | - | IPPT PAN | Staszczak M. | - | IPPT PAN | Cristea M. | - | Petru Poni Institute of Macromolecular Chemistry (RO) |
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