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Holder, Shima
Publications (5 of 5) Show all publications
Das, O., Kim, N. K., Hedenqvist, M. S., Bhattacharyya, D., Johansson, E., Xu, Q. & Holder, S. (2020). Naturally-occurring bromophenol to develop fire retardant gluten biopolymers. Journal of Cleaner Production, 243, Article ID 118552.
Open this publication in new window or tab >>Naturally-occurring bromophenol to develop fire retardant gluten biopolymers
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2020 (English)In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 243, article id 118552Article in journal (Refereed) Published
Abstract [en]

The aim of the study was to impart fire retardancy in wheat gluten polymer through naturally-occurring additives such as lanosol. The fire properties of lanosol were compared with two other conventional brominated fire retardants (Tetrabromobisphenol A and Hexabromocyclododecane). Samples containing fire retardants and gluten were prepared through compression moulding process and then characterised for their fire and mechanical properties. All fire retardants enhanced the reaction-to-fire and thermal properties of gluten while generating V-0 (i.e. vertical position and self-extinguished) ratings in the UL-94 test. The presence of all the fire retardants increased the modulus of the gluten polymer but the fire retardant particles were detrimental for the tensile strength. Nevertheless, lanosol addition delayed ignition and lowered peak heat release rate of gluten by the maximum amount, thereby leading to relatively higher fire performance index (compared to the other fire retardants). Lanosol also allowed the gluten to create a dense char barrier layer during burning that impeded the transfer of heat and flammable volatiles. The fact that only 4 wt% lanosol was able to cause self-extinguishment under direct flame and reduce peak heat release rate by a significant 50% coupled with its inherent occurrence in nature, raises the question if lanosol can be a potential fire retardant in polymeric systems, although it is a bromophenol.

Place, publisher, year, edition, pages
Elsevier, 2020
Keywords
Fire, Lanosol, Polymer, Wheat gluten, Additives, Biopolymers, Polymers, Tensile strength, Hexabromocyclododecanes, Naturally occurring, Peak heat release rates, Polymeric systems, Tetrabromobisphenol A, Vertical positions, Fires
National Category
Polymer Technologies Other Environmental Biotechnology Textile, Rubber and Polymeric Materials
Research subject
Fibre and Polymer Science; Chemical Engineering
Identifiers
urn:nbn:se:kth:diva-263433 (URN)10.1016/j.jclepro.2019.118552 (DOI)000498805600077 ()2-s2.0-85072637743 (Scopus ID)
Funder
Cancerforskningsfonden i Norrland
Note

QC 20191205

Available from: 2019-12-05 Created: 2019-12-05 Last updated: 2022-06-26Bibliographically approved
Holder, S. L., Karlsson, M. E., Olsson, R. S., Hedenqvist, M. S. & Nilsson, F. (2020). Solubility and Diffusivity of Polar and Non-Polar Molecules in Polyethylene-Aluminum Oxide Nanocomposites for HVDC Applications. Energies, 13(3), 722
Open this publication in new window or tab >>Solubility and Diffusivity of Polar and Non-Polar Molecules in Polyethylene-Aluminum Oxide Nanocomposites for HVDC Applications
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2020 (English)In: Energies, E-ISSN 1996-1073, Vol. 13, no 3, p. 722-Article in journal (Refereed) Published
Abstract [en]

The best commercial high-voltage insulation material of today is (crosslinked) ultra-pure low-density polyethylene (LDPE). A 100-fold decrease in electrical conductivity can be achieved by adding 1–3 wt.% of well-dispersed inorganic nanoparticles to the LDPE. One hypothesis is that the nanoparticle surfaces attract ions and polar molecules, thereby cleaning the surrounding polymer, and thus reducing the conductivity. LDPE-based nanocomposites with 1–12 wt.% octyl-coated aluminum oxide nanoparticles were prepared and the sorption and desorption of one polar compound (acetophenone, a crosslinking by-product) and one non-polar compound of a similar size (limonene) were examined. Since the uptake of acetophenone increased linearly with increasing filler content, whereas the uptake of limonene decreased, the surface attraction hypothesis was strengthened. The analytical functions for predicting composite solubility as a function of particle size and filler fraction were derived using experimental solubility measurements and Monte Carlo simulations.

Place, publisher, year, edition, pages
MDPI AG, 2020
Keywords
LDPE, HVDC, nanocomposites, solubility, acetophenone, limonene
National Category
Polymer Chemistry
Identifiers
urn:nbn:se:kth:diva-272989 (URN)10.3390/en13030722 (DOI)000522489000215 ()2-s2.0-85079558896 (Scopus ID)
Funder
SweGRIDS - Swedish Centre for Smart Grids and Energy Storage, ML8
Note

QC 20200624

Available from: 2020-05-04 Created: 2020-05-04 Last updated: 2024-03-15Bibliographically approved
Lee, C.-H., Terbish, N., Holder, S. L., Popuri, S. R. & Nalluri, L. P. (2019). A study on development of alternative biopolymers based proton exchange membrane for microbial fuel cells and effect of blending ratio and ionic crosslinking on bioenergy generation and COD removal. Journal of polymer research, 26(12), Article ID 285.
Open this publication in new window or tab >>A study on development of alternative biopolymers based proton exchange membrane for microbial fuel cells and effect of blending ratio and ionic crosslinking on bioenergy generation and COD removal
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2019 (English)In: Journal of polymer research, ISSN 1022-9760, E-ISSN 1572-8935, Vol. 26, no 12, article id 285Article in journal (Refereed) Published
Abstract [en]

The use of biopolymers as alternative proton exchange membranes (PEMs) is receiving significant attention in microbial fuel cells (MFCs) due to their attractive and competitive physico-chemical properties, eco-friendly behavior and biodegradable nature. In this study we developed the biopolymer-based blend PEMs using chitosan (Cs) alginate (Alg) for bioelectricity production and simultaneous wastewater treatment and also investigated the effect of blending ratio of the membrane and ionic crosslinking between the two biopolymers on MFC performance. The membranes of Cs:Alg were fabricated in volume ratio of 100:0, 80:20, 60:40, 50:50, 40:60, 20:80, and 0:100 via a solution casting and solvent evaporation method followed by crosslinking with phosphoric acid to avoid excess swelling of the hydrophilic polymers and increase the mechanical strength. Among these, the 50:50 ratio membranes exhibited the highest power generation (115 mW/m(2)) with 1340% water uptake, however the membrane with 40:60 ratio displayed maximum COD removal (78.6%) compared to other membranes. The structure and surface morphology of obtained membranes were examined using Infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDX), Sorption and cation exchange capacity, and tensile strength. Sorption, cation exchange capacity and mechanical properties of Cs membranes increased with the addition of Alg with near to stoichiometric ratio.

Place, publisher, year, edition, pages
Springer, 2019
Keywords
Chitosan, Alginate, Proton exchange membrane, Microbial fuel cell, Green energy, Wastewater treatment
National Category
Chemical Sciences
Identifiers
urn:nbn:se:kth:diva-265474 (URN)10.1007/s10965-019-1957-4 (DOI)000498743400001 ()2-s2.0-85075624037 (Scopus ID)
Note

QC 20191217

Available from: 2019-12-17 Created: 2019-12-17 Last updated: 2024-03-15Bibliographically 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: 2024-03-15Bibliographically approved
Holder, S., Hedenqvist, M. S. & Nilsson, F. (2019). Understanding and modelling the diffusion process of low molecular weight substances in polyethylene pipes. Water Research, 301-309
Open this publication in new window or tab >>Understanding and modelling the diffusion process of low molecular weight substances in polyethylene pipes
2019 (English)In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, p. 301-309Article in journal (Refereed) Published
Abstract [en]

Peroxides are widely used as crosslinkers in polyethylene (PE) drinking water pipes. Cross-linked polyethylene (PEX) has better mechanical properties than PE, but peroxide decomposition by-products can migrate from PEX water pipes into the drinking water unless sufficient preventive actions are undertaken. This work systematically examines the migration of tert-Butyl methyl ether (MTBE), a dominating crosslinking by-product from PEX water pipes, into tap water by utilizing both experimental techniques and finite element (FEM) diffusion modeling. The effects of pipe geometry, tap water temperature (23–80 °C), boundary conditions (air or water interface) and degasing (at 180 °C) were considered. The MTBE diffusivity increased strongly with increasing temperature and it was concluded that a desired water quality can be achieved with proper degasing of the PEX pipes. As the FEM simulations were in excellent agreement with the experimental results, the model can accurately predict the MTBE concentration as a function of time, water temperature and PEX pipe geometry, and enable the pipe manufacturers to aid in ensuring desirable drinking water quality.

Place, publisher, year, edition, pages
Elsevier Ltd, 2019
Keywords
Crosslinked polyethylene, Diffusion coefficient, Diffusion model, Drinking water, PEX pipes, Polymers, Diffusion, Oxidation, Peroxides, Phase interfaces, Polyethylenes, Temperature, Water pipelines, Water piping systems, Water quality, Drinking water pipes, Experimental techniques, Increasing temperatures, Low molecular weight, Peroxide decomposition, Tert-butyl methyl ethers, Potable water, deionized water, peroxide, polyethylene, polymer, tap water, tert butyl methyl ether, byproduct, decomposition, molecular analysis, MTBE, pipe, plastic, pollution incidence, water temperature, Article, biodegradation, concentration (parameter), cross linking, diffusivity, finite element analysis, heat treatment, mass fragmentography, molecular weight, priority journal, process model, simulation
National Category
Polymer Chemistry
Identifiers
urn:nbn:se:kth:diva-252470 (URN)10.1016/j.watres.2019.03.084 (DOI)000468253500030 ()30959333 (PubMedID)2-s2.0-85063760634 (Scopus ID)
Note

QC 20190715

Available from: 2019-07-15 Created: 2019-07-15 Last updated: 2022-06-26Bibliographically approved
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