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Hedenqvist, Mikael S.ORCID iD iconorcid.org/0000-0002-6071-6241
Publications (10 of 47) Show all publications
Alipour, N., Vinneras, B., Gouanve, F., Espuche, E. & Hedenqvist, M. S. (2019). A Protein-Based Material from a New Approach Using Whole Defatted Larvae, and Its Interaction with Moisture. Polymers, 11(2), Article ID 287.
Open this publication in new window or tab >>A Protein-Based Material from a New Approach Using Whole Defatted Larvae, and Its Interaction with Moisture
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2019 (English)In: Polymers, ISSN 2073-4360, E-ISSN 2073-4360, Vol. 11, no 2, article id 287Article in journal (Refereed) Published
Abstract [en]

A protein-based material created from a new approach using whole defatted larvae of the Black Soldier fly is presented. The larvae turn organic waste into their own biomass with high content of protein and lipids, which can be used as animal feed or for material production. After removing the larva lipid and adding a plasticizer, the ground material was compression molded into plates/films. The lipid, rich in saturated fatty acids, can be used in applications such as lubricants. The amino acids present in the greatest amounts were the essential amino acids aspartic acid/asparagine and glutamic acid/glutamine. Infrared spectroscopy revealed that the protein material had a high amount of strongly hydrogen-bonded beta-sheets, indicative of a highly aggregated protein. To assess the moisture-protein material interactions, the moisture uptake was investigated. The moisture uptake followed a BET type III moisture sorption isotherm, which could be fitted to the Guggenheim, Anderson and de Boer (GAB) equation. GAB, in combination with cluster size analysis, revealed that the water clustered in the material already at a low moisture content and the cluster increased in size with increasing relative humidity. The clustering also led to a peak in moisture diffusivity at an intermediate moisture uptake.

Place, publisher, year, edition, pages
MDPI, 2019
Keywords
protein, larva, plastic, lipid, Black Soldier fly, moisture sorption
National Category
Polymer Chemistry
Identifiers
urn:nbn:se:kth:diva-246270 (URN)10.3390/polym11020287 (DOI)000460296000101 ()2-s2.0-85061351298 (Scopus ID)
Note

QC 20190126

Available from: 2019-03-26 Created: 2019-03-26 Last updated: 2019-04-04Bibliographically approved
Wei, X.-F., De Vico, L., Larroche, P., Kallio, K., Bruder, S., Bellander, M., . . . Hedenqvist, M. S. (2019). Ageing properties and polymer/fuel interactions of polyamide 12 exposed to (bio)diesel at high temperature. npj Materials Degradation (3), Article ID 1.
Open this publication in new window or tab >>Ageing properties and polymer/fuel interactions of polyamide 12 exposed to (bio)diesel at high temperature
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2019 (English)In: npj Materials Degradation, ISSN 2397-2106, no 3, article id 1Article in journal (Refereed) Published
Abstract [en]

Biodiesel derived from oil crops and animal fats has been developed as a promising carbon-neutral alternative to petroleum fuels in the transport sector, but the compatibility between biodiesel/petroleum diesel and polymer components in the automotive fuel system has not been free from controversy. In this present study, the degradation of polyamide 12 (PA12), one of the most common polymers used in vehicle fuel systems, has been investigated after exposure to petroleum diesel, biodiesel and a mixture of these (20 vol.% of biodiesel/80 vol.% petroleum diesel). Fuel sorption kinetics, glass transition temperature data and mechanical properties all showed that the fuels plasticized the PA12. In addition, monomers and oligomers were extracted from PA12 by the fuels. The long-term exposure led to oxidation and an annealing-induced increase in crystallinity of the polymer. The plasticization, oxidation and annealing effects were combined with the tensile mechanical properties to assess the overall degree of ageing and degradation of the PA12 material. The fuel-polymer interactions and ageing mechanisms, demonstrated here at high temperature for PA12, are 'generic' in the sense that they are also expected to occur, to various degrees, with many other polymers and they indicate that care should be taken when choosing polymers in applications where they will be exposed to fuels at high temperature.

National Category
Textile, Rubber and Polymeric Materials
Identifiers
urn:nbn:se:kth:diva-260464 (URN)
Note

QC 20191111

Available from: 2019-09-30 Created: 2019-09-30 Last updated: 2019-11-11Bibliographically approved
Das, O., Hedenqvist, M. S., Johansson, E., Olsson, R., Loho, T. A., Capezza, A. J., . . . Holder, S. (2019). An all-gluten biocomposite: Comparisons with carbon black and pine char composites. Composites. Part A, Applied science and manufacturing, 120, 42-48
Open this publication in new window or tab >>An all-gluten biocomposite: Comparisons with carbon black and pine char composites
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2019 (English)In: Composites. Part A, Applied science and manufacturing, ISSN 1359-835X, E-ISSN 1878-5840, Vol. 120, p. 42-48Article in journal (Refereed) Published
Abstract [en]

Three different charcoals (gluten char, pine bark char and carbon black) were used to rectify certain property disadvantages of wheat gluten plastic. Pyrolysis process of gluten was investigated by analysing the compounds released at different stages. Nanoindentation tests revealed that the gluten char had the highest hardness (ca. 0.5 GPa) and modulus (7.8 GPa) followed by pine bark char and carbon black. The addition of chars to gluten enhanced the indenter-modulus significantly. Among all the charcoals, gluten char was found to impart the best mechanical and water resistant properties. The addition of only 6 wt% gluten char to the protein caused a substantial reduction in water uptake (by 38%) and increase of indenter-modulus (by 1525%). It was shown that it is possible to obtain protein biocomposites where both the filler and the matrix are naturally sourced from the same material, in this case, yielding an all-gluten derived biocomposite.

Place, publisher, year, edition, pages
Elsevier, 2019
Keywords
(Nominated) Biochar, A. Biocomposite, A. Polymer-matrix composites (PMCs), B. Hardness
National Category
Polymer Technologies
Identifiers
urn:nbn:se:kth:diva-246431 (URN)10.1016/j.compositesa.2019.02.015 (DOI)000463304100006 ()2-s2.0-85062035485 (Scopus ID)
Note

QC 20190402

Available from: 2019-04-02 Created: 2019-04-02 Last updated: 2019-04-29Bibliographically approved
Koemmling, A., Jaunich, M., Pourmand, P., Wolff, D. & Hedenqvist, M. S. (2019). Analysis of O-Ring Seal Failure under Static Conditions and Determination of End-of-Lifetime Criterion. Polymers, 11(8), Article ID 1251.
Open this publication in new window or tab >>Analysis of O-Ring Seal Failure under Static Conditions and Determination of End-of-Lifetime Criterion
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2019 (English)In: Polymers, ISSN 2073-4360, E-ISSN 2073-4360, Vol. 11, no 8, article id 1251Article in journal (Refereed) Published
Abstract [en]

Determining a suitable and reliable end-of-lifetime criterion for O-ring seals is an important issue for long-term seal applications. Therefore, seal failure of ethylene propylene diene rubber (EPDM) and hydrogenated nitrile butadiene rubber (HNBR) O-rings aged in the compressed state at 125 degrees C and at 150 degrees C for up to 1.5 years was analyzed and investigated under static conditions, using both non-lubricated and lubricated seals. Changes of the material properties were analyzed with dynamic-mechanical analysis and permeability experiments. Indenter modulus measurements were used to investigate DLO effects. It became clear that O-rings can remain leak-tight under static conditions even when material properties have already degraded considerably, especially when adhesion effects are encountered. As a feasible and reliable end-of-lifetime criterion for O-ring seals under static conditions should include a safety margin for slight dimensional changes, a modified leakage test involving a small and rapid partial decompression of the seal was introduced that enabled determining a more realistic but still conservative end-of-lifetime criterion for an EPDM seal.

Place, publisher, year, edition, pages
MDPI, 2019
Keywords
EPDM, HNBR, seal failure, leak-tightness, DLO, oxygen permeability, DMA, indenter modulus
National Category
Polymer Chemistry
Identifiers
urn:nbn:se:kth:diva-261040 (URN)10.3390/polym11081251 (DOI)000484552900021 ()31362423 (PubMedID)
Note

QC 20191002

Available from: 2019-10-02 Created: 2019-10-02 Last updated: 2019-10-02Bibliographically approved
Daenicke, J., Schubert, D. W., Hedenqvist, M. S., Linde, E., Sigl, T. & Horch, R. E. (2019). Evaluation of the influence of crosslink density and penetrant size on the diffusion properties of silicone oils into silicone elastomers. In: Proceedings of the Europe/Africa Conference Dresden 2017 – Polymer Processing Society PPS: . Paper presented at 2017 Europe/Africa Regional Conference of the Polymer Processing Society (PPS), Dresden, Germany, 27 June 2017 through 29 June 2017. American Institute of Physics (AIP), 2055
Open this publication in new window or tab >>Evaluation of the influence of crosslink density and penetrant size on the diffusion properties of silicone oils into silicone elastomers
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2019 (English)In: Proceedings of the Europe/Africa Conference Dresden 2017 – Polymer Processing Society PPS, American Institute of Physics (AIP), 2019, Vol. 2055Conference paper, Published paper (Refereed)
Abstract [en]

Driven by the continuing discussion on safety and quality of silicone breast implants, they have turned into focus of this study with respect to the diffusivity of low molar mass components from the silicone gel filling into the silicone breast implant shell. Therefore, the diffusivity of silicone oils into silicone elastomers were analysed by means of the crosslink density and the penetrant size. The study was focused on the diffusion of the cyclic siloxanes Octamethylcyclotetrasiloxane (D4), Decamethylcyclopentasiloxane (D5) and Dodecamethyl-cyclohexasiloxane (D6) due to their potential occurrence in silicone breast implants. The analysis of the diffusion behavior was carried out with silicone breast implant shells taken from explants and tailor-made silicone elastomer samples varying in crosslink density. Therefore, sorption experiments were performed. The subsequent evaluation of the sorption data yield to the corresponding diffusion properties. Based on the diffusion coefficient related to the crosslink density a model was developed to describe the material behavior.

Place, publisher, year, edition, pages
American Institute of Physics (AIP), 2019
Series
AIP Conference Proceedings, ISSN 0094-243X ; 2055
National Category
Other Materials Engineering
Identifiers
urn:nbn:se:kth:diva-244218 (URN)10.1063/1.5084878 (DOI)000464909300077 ()2-s2.0-85061087077 (Scopus ID)9780735417830 (ISBN)
Conference
2017 Europe/Africa Regional Conference of the Polymer Processing Society (PPS), Dresden, Germany, 27 June 2017 through 29 June 2017
Note

QC 20190218

Available from: 2019-02-18 Created: 2019-02-18 Last updated: 2019-05-20Bibliographically approved
Rehman, H. U., Chen, Y., Hedenqvist, M. S., Pathan, R., Liu, H., Wang, H., . . . Li, H. (2019). High-cycle-life and high-loading copolymer network with potential application as a soft actuator. Materials & design, 182, Article ID UNSP 108010.
Open this publication in new window or tab >>High-cycle-life and high-loading copolymer network with potential application as a soft actuator
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2019 (English)In: Materials & design, ISSN 0264-1275, E-ISSN 1873-4197, Vol. 182, article id UNSP 108010Article in journal (Refereed) Published
Abstract [en]

Thermo-responsive polymer materials ate appealing in emerging fields including soft robotics, artificial muscles, and actuators. However, realising a single smart polymer material that can achieve immense strain, fast actuation, and high loading remains a challenge. We attempted to address these limitations by fabricating a thermo-responsive copolymer network structure of poly(urethane-caprolactone-siloxane). The relative concentrations of these precursors were adjusted to realise a high mechanical strength of >= 17 MPa, 100% shape fixation, and a quick shape recovery time of <= 15 s. Experimental results revealed that the soft segments largely determines the extensibility and crystallinity of the copolymer material. The thermal gradient of the soft part enables the copolymer to self-heal during shape recovery. The copolymer network was applied to a load lifting device as an artificial muscle and was able to lift 200 times its weight with a short response time of <5 s and maximum power density that was half that of mammalian skeletal muscles. With its fast actuation, high loading, and self-healing abilities, the developed therrno-activated smart copolymer material is potentially applicable to a wide range of fields such as soft robotics, biomimetic devices, and prosthetics.

Place, publisher, year, edition, pages
ELSEVIER SCI LTD, 2019
Keywords
Shape memory, Self-healing, Artificial muscle, Polyurethane, Polydimethylsiloxane
National Category
Chemical Sciences
Identifiers
urn:nbn:se:kth:diva-262763 (URN)10.1016/j.matdes.2019.108010 (DOI)000488458700014 ()2-s2.0-85068789547 (Scopus ID)
Note

QC 20191022

Available from: 2019-10-22 Created: 2019-10-22 Last updated: 2019-10-22Bibliographically approved
Ceresino, E. B., Kuktaite, R., Sato, H. H., Hedenqvist, M. S. & Johansson, E. (2019). Impact of gluten separation process and transglutaminase source on gluten based dough properties. Food Hydrocolloids, 87, 661-669
Open this publication in new window or tab >>Impact of gluten separation process and transglutaminase source on gluten based dough properties
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2019 (English)In: Food Hydrocolloids, ISSN 0268-005X, E-ISSN 1873-7137, Vol. 87, p. 661-669Article in journal (Refereed) Published
Abstract [en]

This study evaluated the effect of the wheat gluten (WG) separation process and transglutaminase (TG) microbial source on WG dough quality, and opportunities to use these factors to tailor dough quality. Two types of gluten (harshly and mildly separated), two types of TG (commercial and novel SB6), and three TG concentrations were evaluated for effects on dough mixing properties, protein structure and solubility. Mildly separated gluten improved dough development parameters, resulting into higher values of most compared with harshly separated gluten. Despite more strongly cross-linked proteins being found in the harshly separated gluten, both gluten types showed similar levels of cross-linking at optimum mixing time, although differences in the secondary protein structure were indicated. Thus, disulfide-sulfhydryl exchange reactions were found to be promoted by mixing, although restrictions on establishment of new bonds because of prior cross-links in the material were clearly indicated. Degree of polymerization in doughs made from mildly separated gluten increased to varying extents with TG addition depending on TG source and concentration. Thus, for the first time, we show that an appropriate combination of WG separation procedure and TG source can be used to tailor gluten dough end-use properties.

Place, publisher, year, edition, pages
Elsevier, 2019
Keywords
Cross-linking, Gluten, Polymerization, Separation treatment, Transglutaminase
National Category
Chemical Sciences
Identifiers
urn:nbn:se:kth:diva-236322 (URN)10.1016/j.foodhyd.2018.08.035 (DOI)000447623600070 ()2-s2.0-85053525214 (Scopus ID)
Note

QC 20181120

Available from: 2018-11-20 Created: 2018-11-20 Last updated: 2018-11-20Bibliographically approved
Muneer, F., Johansson, E., Hedenqvist, M. S., Plivelic, T. S. & Kuktaite, R. (2019). Impact of pH Modification on Protein Polymerization and Structure-Function Relationships in Potato Protein and Wheat Gluten Composites. International Journal of Molecular Sciences, 20(1), Article ID 58.
Open this publication in new window or tab >>Impact of pH Modification on Protein Polymerization and Structure-Function Relationships in Potato Protein and Wheat Gluten Composites
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2019 (English)In: International Journal of Molecular Sciences, ISSN 1422-0067, E-ISSN 1422-0067, Vol. 20, no 1, article id 58Article in journal (Refereed) Published
Abstract [en]

Wheat gluten (WG) and potato protein (PP) were modified to a basic pH by NaOH to impact macromolecular and structural properties. Films were processed by compression molding (at 130 and 150 degrees C) of WG, PP, their chemically modified versions (MWG, MPP) and of their blends in different ratios to study the impact of chemical modification on structure, processing and tensile properties. The modification changed the molecular and secondary structure of both protein powders, through unfolding and re-polymerization, resulting in less cross-linked proteins. The beta-sheet formation due to NaOH modification increased for WG and decreased for PP. Processing resulted in cross-linking of the proteins, shown by a decrease in extractability; to a higher degree for WG than for PP, despite higher beta-sheet content in PP. Compression molding of MPP resulted in an increase in protein cross-linking and improved maximum stress and extensibility as compared to PP at 130 degrees C. The highest degree of cross-linking with improved maximum stress and extensibility was found for WG/MPP blends compared to WG/PP and MWG/MPP at 130 degrees C. To conclude, chemical modification of PP changed the protein structures produced under harsh industrial conditions and made the protein more reactive and attractive for use in bio-based materials processing, no such positive gains were seen for WG.

Place, publisher, year, edition, pages
MDPI, 2019
Keywords
wheat gluten, potato protein, chemical pre-treatment, structural profile, tensile properties
National Category
Polymer Chemistry
Identifiers
urn:nbn:se:kth:diva-246297 (URN)10.3390/ijms20010058 (DOI)000459747700058 ()30586846 (PubMedID)2-s2.0-85059240280 (Scopus ID)
Note

QC 20190321

Available from: 2019-03-22 Created: 2019-03-22 Last updated: 2019-06-11Bibliographically approved
Moyassari, A., Gkourmpis, T., Hedenqvist, M. S. & Gedde, U. W. (2019). Molecular dynamics simulation of linear polyethylene blends: Effect of molar mass bimodality on topological characteristics and mechanical behavior. Polymer, 161, 139-150
Open this publication in new window or tab >>Molecular dynamics simulation of linear polyethylene blends: Effect of molar mass bimodality on topological characteristics and mechanical behavior
2019 (English)In: Polymer, ISSN 0032-3861, E-ISSN 1873-2291, Vol. 161, p. 139-150Article in journal (Refereed) Published
Abstract [en]

Blending different molar mass fractions of polyethylene (PE) in order to obtain materials with higher fracture toughness has previously proven beneficial. Our approach has been to use coarse-grained (CG) molecular dynamics (MD) simulations to obtain semicrystalline polyethylene systems on a nanoscale, and then draw them in order to mimic tensile testing. The CG potentials were derived, validated and utilized to simulate melt equilibration, cooling, crystallization and mechanical deformation. Crystallinity, tie chain and entanglement concentrations were continuously monitored. During crystallization, the low molar mass fraction disentangled to a greater degree and ended up with a lower entanglement density than the high molar mass fraction, although the tie chain concentration was higher for the low molar mass fraction. The deformation behavior of semicrystalline PE above its glass transition temperature was then assessed in a uniaxial tensile deformation simulation. The low-strain mechanical properties (i.e. elastic modulus, yield stress and strain) were in accordance with the literature. The high-strain mechanical features and toughness were improved in bimodal systems. The presence of a high molar mass fraction in bimodal systems was shown to affect the crystallinity and tie chain concentration during the strain hardening, leading to tougher model systems. Finally, the bimodal system with equal shares of the molar mass fractions showed the highest toughness and the best ultimate mechanical properties while having a concentration of tie chains and entanglements intermediate between the values for the other systems. This was a clear sign of the non-exclusive role of tie chains and entanglements in the mechanical behavior of bimodal PE and more generally of semicrystalline polymers at high strains.

Place, publisher, year, edition, pages
ELSEVIER SCI LTD, 2019
Keywords
Semicrystalline polyethylene, Coarse-grained molecular dynamics, Tie chains and entanglements
National Category
Materials Engineering
Identifiers
urn:nbn:se:kth:diva-241308 (URN)10.1016/j.polymer.2018.12.012 (DOI)000454931700016 ()2-s2.0-85059303277 (Scopus ID)
Note

QC 20190125

Available from: 2019-01-25 Created: 2019-01-25 Last updated: 2019-01-25Bibliographically approved
Moyassari, A., Gkourmpis, T., Hedenqvist, M. S. & Gedde, U. W. (2019). Molecular Dynamics Simulations of Short-Chain Branched Bimodal Polyethylene: Topological Characteristics and Mechanical Behavior. Macromolecules, 52(3), 807-818
Open this publication in new window or tab >>Molecular Dynamics Simulations of Short-Chain Branched Bimodal Polyethylene: Topological Characteristics and Mechanical Behavior
2019 (English)In: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835, Vol. 52, no 3, p. 807-818Article in journal (Refereed) Published
Abstract [en]

It has previously been shown that polyethylene (PE) with a bimodal molar mass distribution has a high fracture toughness. Our approach has been to use coarse-grained (CG) molecular dynamics (MD) simulations to investigate the effects of including short-chain branches in the high molar mass fraction of bimodal PE on topological features and mechanical behavior of the material. The CG potentials were derived, validated, and utilized to simulate melt equilibration, cooling, crystallization, and mechanical deformation. Crystallinity, tie chain, and entanglement concentrations were continuously monitored. During crystallization, the branched bimodal systems disentangled to a lesser degree and ended up with a higher entanglement density than the linear bimodal systems simulated in our previous study. The increase in entanglement concentration was proportional to the content of the branched high molar mass fraction. A significantly higher tie chain concentration was obtained in the short-chain branched bimodal systems than in the linear systems. The increase in the number of ties was more pronounced than the increase in the number of entanglements. The tie chain concentration was not proportional to the content of the high molar mass fraction. Despite a lower crystal thickness and content, the elastic modulus and yield stress values were higher in the branched bimodal systems. A more pronounced strain hardening region was observed in the branched systems. It was suggested that the higher tie chain and entanglement concentration prior to the deformation, the more extensive disentanglement during the deformation, and the disappearance of formed voids prior to failure point were the reasons for the observed higher toughness of the short-chain branched bimodal PE compared with that of the linear bimodal systems. The toughest system, which contained respectively 25 and 75 wt % low molar mass and branched high molar mass fractions, had the highest tie chain concentration and the second highest entanglement concentration of the simulated systems.

Place, publisher, year, edition, pages
American Chemical Society (ACS), 2019
National Category
Polymer Chemistry
Identifiers
urn:nbn:se:kth:diva-245925 (URN)10.1021/acs.macromol.8b01874 (DOI)000458937700004 ()2-s2.0-85061669017 (Scopus ID)
Note

QC 20190312

Available from: 2019-03-12 Created: 2019-03-12 Last updated: 2019-03-12Bibliographically approved
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ORCID iD: ORCID iD iconorcid.org/0000-0002-6071-6241

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