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Andrade EMR, Paixão L, Mendes BM, Fonseca TCF. RFPID: development and 3D-printing of a female physical phantom for whole-body counter. Biomed Phys Eng Express 2024; 10:045015. [PMID: 38697045 DOI: 10.1088/2057-1976/ad4650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 05/02/2024] [Indexed: 05/04/2024]
Abstract
Whole-body counters (WBC) are used in internal dosimetry forin vivomonitoring in radiation protection. The calibration processes of a WBC set-up include the measurement of a physical phantom filled with a certificate radioactive source that usually is referred to a standard set of individuals determined by the International Commission on Radiological Protection (ICRP). The aim of this study was to develop an anthropomorphic and anthropometric female physical phantom for the calibration of the WBC systems. The reference female computational phantom of the ICRP, now called RFPID (Reference Female Phantom for Internal Dosimetry) was printed using PLA filament and with an empty interior. The goal is to use the RFPID to reduce the uncertainties associated within vivomonitoring system. The images which generated the phantom were manipulated using ImageJ®, Amide®, GIMP®and the 3D Slicer®software. RFPID was split into several parts and printed using a 3D printer in order to print the whole-body phantom. The newly printed physical phantom RFPID was successfully fabricated, and it is suitable to mimic human tissue, anatomically similar to a human body i.e., size, shape, material composition, and density.
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Affiliation(s)
- E M R Andrade
- Nuclear Engineering Department, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
- Nuclear Technology Development Center, Belo Horizonte, Minas Gerais, Brazil
| | - L Paixão
- Anatomy and Imaging Department, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - B M Mendes
- Nuclear Technology Development Center, Belo Horizonte, Minas Gerais, Brazil
| | - T C F Fonseca
- Nuclear Engineering Department, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
- Nuclear Technology Development Center, Belo Horizonte, Minas Gerais, Brazil
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Orellana-Barrasa J, Tarancón S, Pastor JY. Effects of Accelerating the Ageing of 1D PLA Filaments after Fused Filament Fabrication. Polymers (Basel) 2022; 15:69. [PMID: 36616419 PMCID: PMC9824215 DOI: 10.3390/polym15010069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 12/15/2022] [Accepted: 12/21/2022] [Indexed: 12/28/2022] Open
Abstract
The effects of post-treatment temperature-based methods for accelerating the ageing of PLA were studied on 1D single-PLA filaments after fused filament fabrication (FFF). The goal was to answer the questions whether the PLA can be safely aged-i.e., without degrading-at higher temperatures; at which temperatures, if any; how long it takes for the PLA to fully age at the chosen temperature; and which are the main differences between the material aged at room temperature and the material aged at higher temperatures. We also share other helpful information found. The use of 1D filaments allows for decoupling the variables related to the 3D structure (layer height, raster angle, infill density, and layers adhesion) from the variables solely related to the material (here, we analysed the molecular weight, the molecular orientation, and the crystallinity). 1D PLA filaments were aged at 20, 39, 42, 51, 65, 75, and 80 °C in a water-bath-inspired process in which the hydrolytic degradation of the PLA was minimised for the ageing temperatures of interest. Those temperatures were selected based on a differential scanning calorimetry (DSC) scan of the PLA right after it was printed in order to study the most effective ageing temperature, 39 °C, and highlight possible degradation mechanisms during ageing. The evolution of the thermal and mechanical properties of the PLA filaments at different temperatures was recorded and compared with those of the material aged at room temperature. A DSC scan was used to evaluate the thermal and physical properties, in which the glass transition, enthalpic relaxation, crystallisation, and melting reactions were analysed. A double glass transition was found, and its potential implications for the scientific community are discussed. Tensile tests were performed to evaluate the tensile strength and elastic modulus. The flow-induced molecular orientation, the degradation, the logistic fitting, and the so-called summer effect-the stabilisation of properties at higher values when aged at higher temperatures-are discussed to assess the safety of accelerating the ageing rate and the differences between the materials aged at different temperatures. It was found that the PLA aged at 39 °C (1) reached almost stable properties with just one day of ageing, i.e., the ageing rate accelerated by 875% for the elastic modulus and by 1635% for the yield strength; (2) the stable properties were higher than those from the PLA aged at room temperature; and (3) no signs of degradation were identified for the ageing temperature of interest.
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Affiliation(s)
| | - Sandra Tarancón
- Centro de Investigación en Materiales Estructurales (CIME), Universidad Politécnica de Madrid, 28040 Madrid, Spain
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Czechowski L, Kedziora S, Museyibov E, Schlienz M, Szatkowski P, Szatkowska M, Gralewski J. Influence of UV Ageing on Properties of Printed PLA Containing Graphene Nanopowder. MATERIALS (BASEL, SWITZERLAND) 2022; 15:ma15228135. [PMID: 36431621 PMCID: PMC9699029 DOI: 10.3390/ma15228135] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 11/07/2022] [Accepted: 11/14/2022] [Indexed: 05/27/2023]
Abstract
The present paper analyses the properties of printed polylactic acid (PLA) samples with admixtures of graphene nanopowder (GNP) at wt. 1%, 2% and 4%. The pure polylactide and admixed polylactide printed samples were examined to determine their chemical-physical properties, stiffness, and strength parameters. The tests of tensile, dynamic mechanical analysis (DMA), difference thermogravimetric (TG), and differential scanning calorimetry (DSC) were executed before and after UV (ultraviolet) treatment. The first part of the paper shows the process of manufacturing granulates and filaments mixed with graphene. The second part of the paper concerns the results of the tests made on printed samples. The analysed samples were printed using a Prusa i3 MK3 printer. It transpired that the content of graphene at 1% improved the mechanical parameters of the printed composite by organising its structure. Increasing the amount of graphene caused the values of the measured parameters to drop. This research indicates how important it is to determine the optimal values of nanoadditives in biopolymers.
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Affiliation(s)
- Leszek Czechowski
- Department of Strength of Materials, Lodz University of Technology, 90-537 Lodz, Poland
- Faculty of Science, Technology and Medicine, Luxembourg University, L-1359 Luxembourg, Luxembourg
| | - Slawomir Kedziora
- Faculty of Science, Technology and Medicine, Luxembourg University, L-1359 Luxembourg, Luxembourg
| | - Elvin Museyibov
- Faculty of Science, Technology and Medicine, Luxembourg University, L-1359 Luxembourg, Luxembourg
| | - Markus Schlienz
- Faculty of Science, Technology and Medicine, Luxembourg University, L-1359 Luxembourg, Luxembourg
| | - Piotr Szatkowski
- Faculty of Materials Science and Ceramics, University of Science and Technology, 30-059 Krakow, Poland
| | - Martyna Szatkowska
- Faculty of Materials Science and Ceramics, University of Science and Technology, 30-059 Krakow, Poland
| | - Jacek Gralewski
- Institute of Marketing and Sustainable Development, Lodz University of Technology, 93-590 Lodz, Poland
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Orellana-Barrasa J, Ferrández-Montero A, Ferrari B, Pastor JY. Natural Ageing of PLA Filaments, Can It Be Frozen? Polymers (Basel) 2022; 14:polym14163361. [PMID: 36015618 PMCID: PMC9416607 DOI: 10.3390/polym14163361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 07/08/2022] [Accepted: 08/02/2022] [Indexed: 11/16/2022] Open
Abstract
The physical ageing of polylactic acid (PLA) is a phenomenon that changes the material’s properties over time. This ageing process is highly dependent on ambient variables, such as temperature and humidity. For PLA, the ageing is noticeable even at room temperatures, a process commonly referred to as natural ageing. Stopping the ageing by freezing the material can be helpful to preserve the properties of the PLA and stabilise it at any time during its storage until it is required for testing. However, it is essential to demonstrate that the PLA’s mechanical properties are not degraded after defrosting the samples. Four different methods for stopping the ageing (anti-ageing processes) are analysed in this paper—all based on freezing and defrosting the PLA samples. We determine the temperature and ambient water vapor influence during the freezing and defrosting process using desiccant and zip bags. The material form selected is PLA filaments (no bulk material or scaffold structures) printed at 190 °C with diameters between 400 and 550 µm and frozen at −24 °C in the presence or absence of a desiccant. The impact of the anti-ageing processes on PLA’s ageing and mechanical integrity is studied regarding the thermal, mechanical and fractographical properties. In conclusion, an anti-ageing process is defined to successfully stop the natural ageing of the PLA for an indefinite length of time. This process does not affect the mechanical properties or the structural integrity of the PLA. As a result, large quantities of this material can be produced in a single batch and be safely stored to be later characterised under the same manufacturing and ageing conditions, which is currently a limiting factor from an experimental point of view as polymeric filament properties can show significant variety from batch to batch.
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Affiliation(s)
- Jaime Orellana-Barrasa
- Centro de Investigación en Materiales Estructurales (CIME), Universidad Politécnica de Madrid, 28040 Madrid, Spain
- Correspondence:
| | | | - Begoña Ferrari
- Instituto de Cerámica y Vidrio (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain
| | - José Ygnacio Pastor
- Centro de Investigación en Materiales Estructurales (CIME), Universidad Politécnica de Madrid, 28040 Madrid, Spain
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Wannawitayapa W, Yoksan R. Toughening polylactic acid by melt blending with polybutylene adipate‐co‐terephthalate and natural rubber, and the performance of the resulting ternary blends. J Appl Polym Sci 2022. [DOI: 10.1002/app.52693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Wanchana Wannawitayapa
- Department of Packaging and Materials Technology, Faculty of Agro‐Industry Kasetsart University Bangkok Thailand
| | - Rangrong Yoksan
- Department of Packaging and Materials Technology, Faculty of Agro‐Industry Kasetsart University Bangkok Thailand
- Center for Advanced Studies for Agriculture and Food, Kasetsart University Institute for Advanced Studies Kasetsart University Bangkok Thailand
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Chen Y, Tang T, Ayranci C. Moisture‐induced anti‐plasticization of polylactic acid: Experiments and modeling. J Appl Polym Sci 2022. [DOI: 10.1002/app.52369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Yu Chen
- Department of Mechanical Engineering University of Alberta Edmonton Alberta Canada
| | - Tian Tang
- Department of Mechanical Engineering University of Alberta Edmonton Alberta Canada
| | - Cagri Ayranci
- Department of Mechanical Engineering University of Alberta Edmonton Alberta Canada
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Orellana Barrasa J, Ferrández-Montero A, Ferrari B, Pastor JY. Characterisation and Modelling of PLA Filaments and Evolution with Time. Polymers (Basel) 2021; 13:polym13172899. [PMID: 34502939 PMCID: PMC8434208 DOI: 10.3390/polym13172899] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 08/12/2021] [Accepted: 08/23/2021] [Indexed: 01/20/2023] Open
Abstract
The properties of polylactic acid (PLA) filaments have not yet been analysed in detail, and they are strongly affected by the extrusion process used in some additive manufacturing systems. Here we present the mechanical, thermal, physical, and fractographical properties of an extruded filament (not the bulk material or scaffolds), the basic building block of any PLA structure printed via material extrusion. This research aims to create a reference point for the modelisation of additively manufactured structures via extrusion processes, as the main building block is characterised in detail for a deep understanding. Furthermore, we investigated the natural ageing (up to one year), the effect of the printing (extruding) temperature (180 and 190 °C), and the effect of the crosshead speed during the tensile tests (10−1 to 102 mm/min) to provide a deeper analysis of the material. The results showed that the material extruded at 190 °C performed better than the material extruded at 180 °C. However, after one hundred days of natural ageing, both materials behaved similarly. This was related to the flow-induced molecular orientation during the extrusion. The crosshead rate produced a logarithmic increase of the mechanical properties, consistent with the Eyring model. Additionally, the ageing produced significant changes in both the elastic modulus and the yield strength: from 2.4 GPa and 40 MPa, in one-day-aged samples, up to 4 GPa and 62 MPa once entirely aged. Finally, it was observed that the glass transition and the enthalpic relaxation increased with ageing, agreeing with the Kohlraushch–William–Watts model.
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Affiliation(s)
- Jaime Orellana Barrasa
- Departamento de Ciencia de Materiales-CIME, Universidad Politécnica de Madrid, 28040 Madrid, Spain;
- Correspondence:
| | - Ana Ferrández-Montero
- Instituto de Cerámicay Vidrio (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain; (A.F.-M.); (B.F.)
- Laboratory of Physicochemistry of Polymers and Interfaces (LPPI), CY Cergy Paris University, Neuville-sur-Oise, 95031 Cergy, France
| | - Begoña Ferrari
- Instituto de Cerámicay Vidrio (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain; (A.F.-M.); (B.F.)
| | - José Ygnacio Pastor
- Departamento de Ciencia de Materiales-CIME, Universidad Politécnica de Madrid, 28040 Madrid, Spain;
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Dynamics of the α-relaxation during the crystallization of PLLA and the effect of thermal annealing under humid atmosphere. Polym Degrad Stab 2019. [DOI: 10.1016/j.polymdegradstab.2019.03.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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9
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Wurm MC, Möst T, Bergauer B, Rietzel D, Neukam FW, Cifuentes SC, Wilmowsky CV. In-vitro evaluation of Polylactic acid (PLA) manufactured by fused deposition modeling. J Biol Eng 2017; 11:29. [PMID: 28919925 PMCID: PMC5594599 DOI: 10.1186/s13036-017-0073-4] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2017] [Accepted: 08/01/2017] [Indexed: 12/02/2022] Open
Abstract
Background With additive manufacturing (AM) individual and biocompatible implants can be generated by using suitable materials. The aim of this study was to investigate the biological effects of polylactic acid (PLA) manufactured by Fused Deposition Modeling (FDM) on osteoblasts in vitro according to European Norm / International Organization for Standardization 10,993–5. Method Human osteoblasts (hFOB 1.19) were seeded onto PLA samples produced by FDM and investigated for cell viability by fluorescence staining after 24 h. Cell proliferation was measured after 1, 3, 7 and 10 days by cell-counting and cell morphology was evaluated by scanning electron microscopy. For control, we used titanium samples and polystyrene (PS). Results Cell viability showed higher viability on PLA (95,3% ± 2.1%) than in control (91,7% ±2,7%). Cell proliferation was highest in the control group (polystyrene) and higher on PLA samples compared to the titanium samples. Scanning electron microscopy revealed homogenous covering of sample surface with regularly spread cells on PLA as well as on titanium. Conclusion The manufacturing of PLA discs from polylactic acid using FDM was successful. The in vitro investigation with human fetal osteoblasts showed no cytotoxic effects. Furthermore, FDM does not seem to alter biocompatibility of PLA. Nonetheless osteoblasts showed reduced growth on PLA compared to the polystyrene control within the cell experiments. This could be attributed to surface roughness and possible release of residual monomers. Those influences could be investigated in further studies and thus lead to improvement in the additive manufacturing process. In addition, further research focused on the effect of PLA on bone growth should follow. In summary, PLA processed in Fused Deposition Modelling seems to be an attractive material and method for reconstructive surgery because of their biocompatibility and the possibility to produce individually shaped scaffolds.
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Affiliation(s)
- Matthias C Wurm
- Department of Oral and Maxillofacial Surgery, University Hospital Erlangen, Glueckstrasse 11, 91054 Erlangen, Germany
| | - Tobias Möst
- Department of Oral and Maxillofacial Surgery, University Hospital Erlangen, Glueckstrasse 11, 91054 Erlangen, Germany
| | - Bastian Bergauer
- Department of Oral and Maxillofacial Surgery, University Hospital Erlangen, Glueckstrasse 11, 91054 Erlangen, Germany
| | - Dominik Rietzel
- Institute for Polymer Technology, Friedrich-Alexander-University Erlangen-Nuremberg, Am Weichselgarten 9, 91058 Erlangen, Germany
| | - Friedrich Wilhelm Neukam
- Department of Oral and Maxillofacial Surgery, University Hospital Erlangen, Glueckstrasse 11, 91054 Erlangen, Germany
| | - Sandra C Cifuentes
- Departamento de Ciencia e Ingeniería de Materiales e Ingeniería Química, IAAB, Universidad Carlos III de Madrid, Avda. de la Universidad, 30, 28911 Leganés, Madrid Spain
| | - Cornelius von Wilmowsky
- Department of Oral and Maxillofacial Surgery, University Hospital Erlangen, Glueckstrasse 11, 91054 Erlangen, Germany
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Widiastuti I, Sbarski I, Masood SH. Sorption characteristic of organic liquid and its effect on the mechanical performance of a PLA-based plastic. J Appl Polym Sci 2016. [DOI: 10.1002/app.43250] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Indah Widiastuti
- Research Group of Mechanical and Automotive Engineering Department of Mechanical Engineering Education; Sebelas Maret University; Jl. Ir. Sutami 36 a Kentingan Surakarta 57126 Indonesia
| | - Igor Sbarski
- Industrial Research Institute, Swinburne University of Technology; John St Hawthorn Melbourne 3122 Australia
| | - SH Masood
- Industrial Research Institute, Swinburne University of Technology; John St Hawthorn Melbourne 3122 Australia
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Georgiopoulos P, Kontou E, Meristoudi A, Pispas S, Chatzinikolaidou M. Τhe effect of silica nanoparticles on the thermomechanical properties and degradation behavior of polylactic acid. J Biomater Appl 2014; 29:662-74. [PMID: 25091863 DOI: 10.1177/0885328214545351] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
In this work a series of polylactic acid/SiO2 nanocomposites have been prepared by a melt mixing procedure. The dispersion quality was examined by scanning electron microscopy. To study the degradation behavior of the polylactic acid/nanocomposites prepared, the samples were immersed in a buffer solution at a temperature of 37℃ with a pH of 7.4 for a time period of up to 23 weeks. These conditions simulate those in the human body, appropriate in medical applications. In order to assess their suitability in biomedical applications, we investigated the biocompatibility of these materials in terms of cell viability, growth, and morphology. A good initial cell adhesion has been detected, supporting their potential use in bone tissue engineering applications. The hydrolytic degradation of polylactic acid, under the prescribed conditions, was studied by the molecular weight reduction in terms of size exclusion chromatography, whereas the progress of thermal stability of polylactic acid and polylactic acid/nanocomposites during aging was tested by thermogravimetric analysis. The evolution of the materials' thermomechanical properties during aging was studied by differential scanning calorimetry, dynamic mechanical analysis, and tensile testing. The crystallization behavior in polylactic acid and the way it is affected by the presence of nanofillers during degradation procedure has been studied and values of 44% crystallinity increment have been found. At the specific aging conditions studied, silica nanoparticles accelerate the degradability of polylactic acid, having a higher impact on Young's modulus, under the specified aging conditions, for 7 weeks and hereafter this acceleration is retarded, due to the crystallinity increment, as a result of the molecular weight reduction.
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Affiliation(s)
- P Georgiopoulos
- School of Applied Mathematical and Physical Sciences, Department of Mechanics, National Technical University of Athens, Athens, Greece
| | - E Kontou
- School of Applied Mathematical and Physical Sciences, Department of Mechanics, National Technical University of Athens, Athens, Greece
| | - A Meristoudi
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, Athens, Greece
| | - S Pispas
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, Athens, Greece
| | - M Chatzinikolaidou
- Department of Materials Science and Technology, University of Crete, Heraklio, Greece Institute of Electronic Structure & Laser, Foundation for Research & Technology Hellas, Heraklio, Greece
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Widiastuti I, Sbarski I, Masood SH. Mechanical response of poly(lactic acid)-based packaging under liquid exposure. J Appl Polym Sci 2014. [DOI: 10.1002/app.40600] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
| | - Igor Sbarski
- Swinburne University of Technology; Melbourne Australia
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Rasselet D, Ruellan A, Guinault A, Miquelard-Garnier G, Sollogoub C, Fayolle B. Oxidative degradation of polylactide (PLA) and its effects on physical and mechanical properties. Eur Polym J 2014. [DOI: 10.1016/j.eurpolymj.2013.10.011] [Citation(s) in RCA: 100] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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14
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Dopico-García MS, Ares-Pernas A, González-Rodríguez MV, López-Vilariño JM, Abad-López MJ. Commercial biodegradable material for food contact: methodology for assessment of service life. POLYM INT 2012. [DOI: 10.1002/pi.4255] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Widiastuti I, Sbarski I, Masood S. Creep behavior of PLA-based biodegradable plastic exposed to a hydrocarbon liquid. J Appl Polym Sci 2012. [DOI: 10.1002/app.37575] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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