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Åkesson, Dan
Publikasjoner (10 av 69) Visa alla publikasjoner
Gustafsson, J., Landberg, M., Bátori, V., Åkesson, D., Taherzadeh, M. J. & Zamani, A. (2019). Development of Bio-Based Films and 3D Objects from Apple Pomace. Polymers, 11(2), Article ID 289.
Åpne denne publikasjonen i ny fane eller vindu >>Development of Bio-Based Films and 3D Objects from Apple Pomace
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2019 (engelsk)Inngår i: Polymers, ISSN 2073-4360, E-ISSN 2073-4360, Vol. 11, nr 2, artikkel-id 289Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Extensive quantities of apple pomace are generated annually but its disposal is still challenging. This study addresses this issue by introducing a new, environmentally-friendly approach for the production of sustainable biomaterials from apple pomace, containing 55.47% free sugars and a water insoluble fraction, containing 29.42 ± 0.44% hemicelluloses, 38.99 ± 0.42% cellulose, and 22.94 ± 0.12% lignin. Solution casting and compression molding were applied to form bio-based films and 3D objects (i.e., fiberboards), respectively. Using glycerol as plasticizer resulted in highly compact films with high tensile strength and low elongation (16.49 ± 2.54 MPa and 10.78 ± 3.19%, respectively). In contrast, naturally occurring sugars in the apple pomace showed stronger plasticizing effect in the films and resulted in a fluffier and connected structure with significantly higher elongation (37.39 ± 10.38% and 55.41 ± 5.38%, respectively). Benefiting from the self-binding capacity of polysaccharides, fiberboards were prepared by compression molding at 100 °C using glycerol or naturally occurring sugars, such as plasticizer. The obtained fiberboards exhibited tensile strength of 3.02–5.79 MPa and elongation of 0.93%–1.56%. Possible applications for apple pomace biomaterials are edible/disposable tableware or food packaging. 

Emneord
apple pomace, biofilm, biomaterials, compression molding, fiberboard, solution casting
HSV kategori
Forskningsprogram
Resursåtervinning; Resursåtervinning
Identifikatorer
urn:nbn:se:hb:diva-15718 (URN)10.3390/polym11020289 (DOI)2-s2.0-85061399977 (Scopus ID)
Tilgjengelig fra: 2019-01-28 Laget: 2019-01-28 Sist oppdatert: 2019-08-07bibliografisk kontrollert
Kumar Ramamoorthy, S., Åkesson, D., Skrifvars, M., Rajan, R. & Periyasamy, A. P. (2019). Mechanical performance of biofibers and their corresponding composites. In: Mohammad Jawaid, Mohamed Thariq, Naheed Saba (Ed.), Mechanical and Physical Testing of Biocomposites, Fibre-Reinforced Composites and Hybrid Composites: . Woodhead Publishing Limited
Åpne denne publikasjonen i ny fane eller vindu >>Mechanical performance of biofibers and their corresponding composites
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2019 (engelsk)Inngår i: Mechanical and Physical Testing of Biocomposites, Fibre-Reinforced Composites and Hybrid Composites / [ed] Mohammad Jawaid, Mohamed Thariq, Naheed Saba, Woodhead Publishing Limited, 2019Kapittel i bok, del av antologi (Fagfellevurdert)
Abstract [en]

This chapter focuses on mechanical performance of biofibers such as flax, hemp, and sisal and their effect on mechanical performance when they are reinforced in thermoset and thermoplastic polymers. The aim of this chapter is to present an overview of the mechanical characterization of the biofibers and their corresponding composites. The mechanical characterization includes tensile, flexural, impact, compressive, shear, toughness, hardness, brittleness, ductility, creep, fatigue, and dynamic mechanical analyses. Detailed studies of each test have been widely reported and an overview is important to relate the studies. Studies pertaining to the topics are cited. The most common materials used in biocomposites are biofibers (also called natural fibers) and petroleum-based polymers such polypropylene. The use of renewable materials in biocomposites has increased in the past couple of decades owing to extensive research on cellulosic fibers and biopolymers based on starch or vegetable oil. Today, research is focused on reinforcing natural fibers in petroleum-based polymers. However, the emphasis is shifting toward the amount of renewable materials in biocomposites, which has led to the use of biopolymers instead of petroleum-based polymers in composites. The mechanical properties of some renewable resource-based composites are comparable to commercially available nonrenewable composites.

Several plant biofibers have been reinforced in thermoplastics or thermosets to manufacture biocomposites because of their specific properties. The Young's modulus of commonly used biofibers such as hemp and flax could be over 50 GPa and therefore they could be good alternatives to glass fibers in several applications. The good mechanical properties of these biofibers influence the composites' mechanical performance when reinforced in polymers. It is important to understand the mechanical performance of these biofibers and biocomposites in a working environment. A detailed discussion about the mechanical performance of commonly used biofibers and composites is provided in this chapter.

sted, utgiver, år, opplag, sider
Woodhead Publishing Limited, 2019
Emneord
Biocomposite, Biofiber, Mechanical properties, Natural fiber, Renewable materials
HSV kategori
Forskningsprogram
Resursåtervinning
Identifikatorer
urn:nbn:se:hb:diva-15228 (URN)10.1016/B978-0-08-102292-4.00014-X (DOI)
Tilgjengelig fra: 2018-10-22 Laget: 2018-10-22 Sist oppdatert: 2018-11-16bibliografisk kontrollert
Bátori, V., Lundin, M., Åkesson, D., Lennartsson, P. R., Taherzadeh, M. J. & Zamani, A. (2019). The Effect of Glycerol, Sugar, and Maleic Anhydride on Pectin-Cellulose Thin Films Prepared from Orange Waste. POLYMERS, 11(3)
Åpne denne publikasjonen i ny fane eller vindu >>The Effect of Glycerol, Sugar, and Maleic Anhydride on Pectin-Cellulose Thin Films Prepared from Orange Waste
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2019 (engelsk)Inngår i: POLYMERS, Vol. 11, nr 3Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

This study was conducted to improve the properties of thin films prepared from orange waste by the solution casting method. The main focus was the elimination of holes in the film structure by establishing better cohesion between the major cellulosic and pectin fractions. For this, a previously developed method was improved first by the addition of sugar to promote pectin gelling, then by the addition of maleic anhydride. Principally, maleic anhydride was introduced to the films to induce cross-linking within the film structure. The effects of concentrations of sugar and glycerol as plasticizers and maleic anhydride as a cross-linking agent on the film characteristics were studied. Maleic anhydride improved the structure, resulting in a uniform film, and morphology studies showed better adhesion between components. However, it did not act as a cross-linking agent, but rather as a compatibilizer. The middle level (0.78%) of maleic anhydride content resulted in the highest tensile strength (26.65 +/- 3.20 MPa) at low (7%) glycerol and high (14%) sugar levels and the highest elongation (28.48% +/- 4.34%) at high sugar and glycerol levels. To achieve a uniform film surface with no holes present, only the lowest (0.39%) level of maleic anhydride was necessary.

Emneord
bio-based, film, mechanical properties, polysaccharides, resource recovery, solution casting, orange waste
HSV kategori
Forskningsprogram
Resursåtervinning; Resursåtervinning
Identifikatorer
urn:nbn:se:hb:diva-21529 (URN)10.3390/polym11030392 (DOI)000464512900002 ()2-s2.0-85066752753 (Scopus ID)
Tilgjengelig fra: 2019-08-06 Laget: 2019-08-06 Sist oppdatert: 2019-08-07
Kumar Ramamoorthy, S., Kuzhanthaivelu, G., Bohlén, M. & Åkesson, D. (2019). Waste Management Option for Bioplastics Alongside Conventional Plastics. In: IRC 2019 International Research Conference Proceedings: . Paper presented at ICWMRE 2019: International Conference on Waste Management, Recycling and Environment, Barcelona, Spain February 11 - 12, 2019..
Åpne denne publikasjonen i ny fane eller vindu >>Waste Management Option for Bioplastics Alongside Conventional Plastics
2019 (engelsk)Inngår i: IRC 2019 International Research Conference Proceedings, 2019Konferansepaper, Oral presentation with published abstract (Fagfellevurdert)
Abstract [en]

Bioplastics can be defined as polymers derived partly or completely from biomass. Bioplastics can be biodegradable such as polylactic acid (PLA) and polyhydroxyalkonoates (PHA); or non-biodegradable (biobased polyethylene (bio-PE), polypropylene (bio-PP), polyethylene terephthalate (bio-PET)). The usage of such bioplastics is expected to increase in the future due to new found interest in sustainable materials. At the same time, these plastics become a new type of waste in the recycling stream. Most countries do not have separate bioplastics collection for it to be recycled or composted. After a brief introduction of bioplastics such as PLA in UK, these plastics are once again replaced by conventional plastics by many establishments due to lack of commercial composting. Recycling companies fear the contamination of conventional plastic in the recycling stream and they said they would have to invest in expensive new equipment to separate bioplastics and recycle it separately. Bioplastics are seen as a threat to the recycling industry as bioplastics may degrade during the mechanical recycling process and the properties of the recycled plastics are seriously impacted. This project studies what happens when bioplastics contaminate conventional plastics.

Three commonly used conventional plastics were selected for this study: polyethylene (PE), polypropylene (PP) and polyethylene terephthalate (PET). In order to simulate contamination, two biopolymers, either polyhydroxyalkanoate (PHA) or thermoplastic starch (TPS) were blended with the conventional polymers. The amount of bioplastics in conventional plastics was either 1% or 5%. The blended plastics were processed again to see the effect of degradation. Mechanical, thermal and morphological properties of these plastics were characterized.

 

The results from contamination showed that the tensile strength and the modulus of PE was almost unaffected whereas the elongation is clearly reduced indicating the increase in brittleness of the plastic. Generally, it can be said that PP is slightly more sensitive to the contamination than PE. This can be explained by the fact that the melting point of PP is higher than for PE and as a consequence, the biopolymer will degrade more quickly. However, the reduction of the tensile properties for PP is relatively modest. It is also important to notice that when plastics are recovered, there will always be a contamination that will reduce the material properties. The reduction of the tensile properties is not necessary larger than if a non-biodegradable polymer would have contaminated PE or PP. The Charpy impact strength is generally a more sensitive test method towards contamination. Again, PE is relatively unaffected by the contamination but for PP there is a relatively large reduction of the impact properties already at 1% contamination.

PET is polyester and it is by its very nature more sensitive to degradation than PE and PP. PET also have a much higher melting point than PE and PP and as a consequence the biopolymer will quickly degrade at the processing temperature of PET. As for the tensile strength, PET can tolerate 1% contamination without any reduction of the tensile strength. However, when the impact strength is examined, it is clear that already at 1% contamination, there is a strong reduction of the properties. It can also be seen that presence of TPS is more detrimental to PET than PHA is. This can be explained by the fact that TPS contain reactive hydroxyl groups that can react with the ester bond of PET. This will in other words lead to degradation of PET.

The thermal properties show the change in the crystallinity. As a general conclusion, it can be said that the plastics become less crystalline when contaminated. The blends were also characterized by SEM. Biphasic morphology can be seen as the two polymers are not truly blendable which also contributes to reduced mechanical properties. Recycling of the contaminated polymer shows an increase in crystallinity. This means that when the polymers are processed, polymer degradation occur causing the polymer chains to gradually become shorter which will enhance the crystallization process.

The study shows that PE is relatively robust againt contamination, while polypropylene (PP) is somewhat more sensitive and polyethylene terephthalate (PET) can be quite sensitive towards contamination.

Emneord
Bioplastics, contamination, recycling, waste management
HSV kategori
Forskningsprogram
Resursåtervinning
Identifikatorer
urn:nbn:se:hb:diva-16032 (URN)
Konferanse
ICWMRE 2019: International Conference on Waste Management, Recycling and Environment, Barcelona, Spain February 11 - 12, 2019.
Tilgjengelig fra: 2019-04-25 Laget: 2019-04-25 Sist oppdatert: 2019-04-29bibliografisk kontrollert
Bátori, V., Åkesson, D., Zamani, A., Taherzadeh, M. J. & Sárvári Horváth, I. (2018). Anaerobic degradation of bioplastics: A review. Waste Management, 80, 406-413
Åpne denne publikasjonen i ny fane eller vindu >>Anaerobic degradation of bioplastics: A review
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2018 (engelsk)Inngår i: Waste Management, Vol. 80, s. 406-413Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Anaerobic digestion (AD) of the organic fraction of municipal solid waste (OFMSW), leading to renewableenergy production in the form of methane, is a preferable method for dealing with the increasing amountof waste. Food waste is separated at the source in many countries for anaerobic digestion. However, thepresence of plastic bags is a major challenge for such processes. This study investigated the anaerobicdegradability of different bioplastics, aiming at potential use as collecting bags for the OFMSW. Thechemical composition of the bioplastics and the microbial community structure in the AD processaffected the biodegradation of the bioplastics. Some biopolymers can be degraded at hydraulic retentiontimes usually applied at the biogas plants, such as poly(hydroxyalkanoate)s, starch, cellulose and pectin,so no possible contamination would occur. In the future, updated standardization of collecting bags forthe OFMSW will be required to meet the requirements of effective operation of a biogas plant.

Emneord
Anaerobic digestion, Biodegradation, Bioplastics, Food waste, Methane, Plastic bags
HSV kategori
Identifikatorer
urn:nbn:se:hb:diva-15152 (URN)10.1016/j.wasman.2018.09.040 (DOI)2-s2.0-85054156950 (Scopus ID)
Tilgjengelig fra: 2018-10-04 Laget: 2018-10-04 Sist oppdatert: 2019-01-25bibliografisk kontrollert
Jabbari, M., Skrifvars, M., Åkesson, D. & Taherzadeh, M. J. (2018). New Solvent for Polyamide 66 and Its Use for Preparing a Single-Polymer Composite-Coated Fabric. International Journal of Polymer Science
Åpne denne publikasjonen i ny fane eller vindu >>New Solvent for Polyamide 66 and Its Use for Preparing a Single-Polymer Composite-Coated Fabric
2018 (engelsk)Inngår i: International Journal of Polymer Science, ISSN 1687-9422, E-ISSN 1687-9430Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Polyamides (PAs) are one of the most important engineering polymers; however, the difficulty in dissolving them hinders their applications. Formic acid (FA) is the most common solvent for PAs, but it has industrial limitations. In this contribution, we proposed a new solvent system for PAs by replacing a portion of the FA with urea and calcium chloride (FAUCa). Urea imparts the hydrogen bonding and calcium ion from the calcium chloride, as a Lewis acid was added to the system to compensate for the pH decrease due to the addition of urea. The results showed that the proposed solvent (FAUCa) could readily dissolve PAs, resulting in a less decrease in the mechanical properties during the dissolution. The composite prepared using the FAUCa has almost the same properties as the one prepared using the FA solution. The solution was applied on a polyamide 66 fabric to make an all-polyamide composite-coated fabric, which then was characterized. The FAUCa solution had a higher viscosity than the one prepared using the neat FA solvent, which can be an advantage in the applications which need higher viscosity like preparing the all-polyamide composite-coated fabric. A more viscous solution makes a denser coating which will increase the water /gas tightness. In conclusion, using the FAUCa solvent has two merits: (1) replacement of 40% of the FA with less harmful and environmentally friendly chemicals and (2) enabling for the preparation of more viscous solutions, which makes a denser coating.

HSV kategori
Forskningsprogram
Resursåtervinning
Identifikatorer
urn:nbn:se:hb:diva-21557 (URN)10.1155/2018/6235165 (DOI)000448619700001 ()2-s2.0-85062636745 (Scopus ID)
Tilgjengelig fra: 2019-08-06 Laget: 2019-08-06 Sist oppdatert: 2019-08-07
Bátori, V., Åkesson, D., Zamani, A. & Taherzadeh, M. J. (2017). Pectin-based Composites. In: Handbook of Composites from Renewable Materials: Biodegradable Materials (pp. 487-518). John Wiley & Sons
Åpne denne publikasjonen i ny fane eller vindu >>Pectin-based Composites
2017 (engelsk)Inngår i: Handbook of Composites from Renewable Materials: Biodegradable Materials, John Wiley & Sons, 2017, s. 487-518Kapittel i bok, del av antologi (Annet vitenskapelig)
Abstract [en]

One third of the cell wall of vascular plants is composed of pectin, which serves as the cementing material for the cellulosic network, behaving as a stabilized gel. Industrially, pectin is produced from juice and sugar production waste. Different sources and extraction conditions result in diversity in characteristics and applications of pectin. Most commonly, pectin is used in the food industry as a gelling and thickening agent and it is favored in the pharmaceutical industry as a carrier for colon-specific drugs. Pectin has good potential to be utilized as a matrix in production of environmentally friendly film packaging as well as biocomposite materials. Pectin is sensitive to chemical reactions and promotes the homogeneous immobilization of cells, genes, and proteins. However, due to limited mechanical properties pectin is not used for structural applications but instead rather for composites in which its biodegradable properties can be utilized. Pectin is often reinforced with hydroxyapatite and biphasic calcium phosphate for bone regeneration and tissue engineering applications. It can also be used as a biosorbent for copper removal from aqueous solutions. Active packaging of nanohybrids composed of pectin and halloysite nanotubes that are loaded with rosemary essential oil is another application of pectin-based composites.

sted, utgiver, år, opplag, sider
John Wiley & Sons, 2017
Emneord
pectin, biodegradable, composite, nanocomposite, renewable, reinforcement
HSV kategori
Forskningsprogram
Resursåtervinning
Identifikatorer
urn:nbn:se:hb:diva-12108 (URN)978-1-119-22379-5 (ISBN)
Tilgjengelig fra: 2017-04-25 Laget: 2017-04-25 Sist oppdatert: 2017-05-04bibliografisk kontrollert
Ramamoorthy, S. K., Åkesson, D., Skrifvars, M. & Baghaei, B. (2017). Preparation and Characterization of Biobased Thermoset Polymers from Renewable Resources and Their Use in Composites. In: Vijay Kumar Thakur, Manju Kumari Thakur, Michael R. Kessler (Ed.), Handbook of Composites from Renewable Materials, Physico-Chemical and Mechanical Characterization: (pp. 425-457). Hoboken, New Jersey, USA: John Wiley & Sons
Åpne denne publikasjonen i ny fane eller vindu >>Preparation and Characterization of Biobased Thermoset Polymers from Renewable Resources and Their Use in Composites
2017 (engelsk)Inngår i: Handbook of Composites from Renewable Materials, Physico-Chemical and Mechanical Characterization / [ed] Vijay Kumar Thakur, Manju Kumari Thakur, Michael R. Kessler, Hoboken, New Jersey, USA: John Wiley & Sons, 2017, s. 425-457Kapittel i bok, del av antologi (Fagfellevurdert)
Abstract [en]

This chapter focuses on physicochemical and mechanical characterization of compositesmade from renewable materials. Most common renewable materials used in composites arenatural fibers and polymers based on starch or vegetable oil. The extent of using renewablematerials in biocomposites has increased during the past decade due to extensive research oncellulosic fibers and biobased polymers. Earlier, the research was focused on using the naturalfibers as reinforcement in crude oil-based polymers such as polypropylene. Later, the emphasisshifted to increase the amount of renewable components in the biocomposites which led tothe introductionof biobased resins in the composites. The properties of some biocompositesare today comparable to the properties for commercially available nonrenewable composites.Several plant biofibers have been used as reinforcement in biobased thermoplastics or thermosetsto manufacture biocomposites. Material characterization is important to understand theperformance of these composites under specific environment. Detailed discussion about themechanical and physicochemical characterization is provided in this chapter. Physicochemicalcharacterization includes chemical composition, density, viscosity, molecular weight, meltingtemperature, crystallinity,morphology, wettability, surface tension, water binding capacity,electricalconductivity, flammability, thermal stability, and swelling. Mechanical characterizationincludes tensile, flexural, impact, compressive, shear, toughness, hardness, brittleness, ductility,creep, fatigue, and dynamic mechanical analysis.

sted, utgiver, år, opplag, sider
Hoboken, New Jersey, USA: John Wiley & Sons, 2017
Emneord
Renewable materials, physicochemical properties, mechanical properties, biocomposites, biopolymers, natural fiber
HSV kategori
Forskningsprogram
Resursåtervinning
Identifikatorer
urn:nbn:se:hb:diva-11889 (URN)2-s2.0-85050924637 (Scopus ID)978-1-119-22366-5 (ISBN)9781119224235 (ISBN)
Tilgjengelig fra: 2017-02-03 Laget: 2017-02-03 Sist oppdatert: 2018-12-01bibliografisk kontrollert
Bátori, V., Jabbari, M., Åkesson, D., Lennartsson, P. R., Taherzadeh, M. J. & Zamani, A. (2017). Production of Pectin-Cellulose Biofilms: A New Approach for Citrus Waste Recycling. International Journal of Polymer Science, 2017, 1-9, Article ID 9732329.
Åpne denne publikasjonen i ny fane eller vindu >>Production of Pectin-Cellulose Biofilms: A New Approach for Citrus Waste Recycling
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2017 (engelsk)Inngår i: International Journal of Polymer Science, ISSN 1687-9422, E-ISSN 1687-9430, Vol. 2017, s. 1-9, artikkel-id 9732329Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

While citrus waste is abundantly generated, the disposal methods used today remain unsatisfactory: they can be deleterious for ruminants, can cause soil salinity, or are not economically feasible; yet citrus waste consists of various valuable polymers. This paper introduces a novel environmentally safe approach that utilizes citrus waste polymers as a biobased and biodegradable film, for example, for food packaging. Orange waste has been investigated for biofilm production, using the gelling ability of pectin and the strength of cellulosic fibres. A casting method was used to form a film from the previously washed, dried, and milled orange waste. Two film-drying methods, a laboratory oven and an incubator shaker, were compared. FE-SEM images confirmed a smoother film morphology when the incubator shaker was used for drying. The tensile strength of the films was 31.67 ± 4.21 and 34.76 ± 2.64 MPa, respectively, for the oven-dried and incubator-dried films, which is within the range of different commodity plastics. Additionally, biodegradability of the films was confirmed under anaerobic conditions. Films showed an opaque appearance with yellowish colour.

HSV kategori
Identifikatorer
urn:nbn:se:hb:diva-12981 (URN)10.1155/2017/9732329 (DOI)000414729600001 ()2-s2.0-85042320662 (Scopus ID)
Tilgjengelig fra: 2017-11-09 Laget: 2017-11-09 Sist oppdatert: 2019-08-07bibliografisk kontrollert
Fazelinejad, S., Åkesson, D. & Skrifvars, M. (2017). Repeated mechanical recycling of polylactic acid filled with chalk. Progress in Rubber, Plastics and Recycling Technology, 1-16
Åpne denne publikasjonen i ny fane eller vindu >>Repeated mechanical recycling of polylactic acid filled with chalk
2017 (engelsk)Inngår i: Progress in Rubber, Plastics and Recycling Technology, ISSN 0266-7320, E-ISSN 1478-2413, s. 1-16Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Polylactic acid (PLA) was compounded with 30 wt% chalk and 5 wt% of a biobased plasticiser on a twin screw extruder. Mechanical recycling of the obtained compound was studied by multiple extrusions up to six cycles. The degradation was monitored by mechanical and thermal tests. Tensile and flexural tests did not reveal any major degradation after six cycles of processing. Characterising the material with differential scanning calorimetry (DSC) did not detect any significant change of the thermal properties. The material was also characterised by FTIR and, again, no significant change was detected. The material was finally characterised by melt flow index and by proton nuclear magnetic resonance (1H-NMR). Both tests revealed that some degradation had occurred. The 1H-NMR clearly showed that the chain length had been reduced. Also, the MFI test showed that degradation had occurred. However, the study reveals that PLA filled with chalk can be recycled by repeated extrusion for up to 6 cycles, without severe degradation. This should be of relevance when considering the end-of-life treatment of polymer products made from PLA.

Emneord
Calcium carbonate, Chalk, Inorganic filler Mechanical recycling, PLA
HSV kategori
Forskningsprogram
Resursåtervinning
Identifikatorer
urn:nbn:se:hb:diva-13453 (URN)000394414200001 ()2-s2.0-85016319877 (Scopus ID)
Tilgjengelig fra: 2018-01-14 Laget: 2018-01-14 Sist oppdatert: 2018-12-01bibliografisk kontrollert
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