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  • 1.
    Abid, Fahim
    et al.
    KTH.
    Ghorbani, Hossein
    Pourrahimi, Amir Masoud
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Edin, Hans Ezz
    KTH, Skolan för elektro- och systemteknik (EES), Elektroteknisk teori och konstruktion.
    Differences in morphology and polarization properties of heat-treated XLPE and LDPE insulation2016Inngår i: 2016 IEEE CONFERENCE ON ELECTRICAL INSULATION AND DIELECTRIC PHENOMENA (IEEE CEIDP), IEEE conference proceedings, 2016, s. 113-116Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Cross-linked polyethylene (XLPE) is the most commonly used insulating material for extruded high voltage cable applications. Degassing is a heat-treatment process that is performed to remove methane from XLPE insulation which is formed during the crosslinking reactions as a by-product. Apart from removing methane, heat-treatment influences the electrical properties through changing the morphology due to annealing and also removal of polar crosslinking by-products. Scanning electron microscopy (SEM) is generally used to observe the changes in crystalline structure of the polymer. Frequency domain spectroscopy (FDS) is widely used to study polarization properties of dielectric materials. In this study these two methods are used for a comparative analysis of XLPE and LDPE subjected to different heat-treatment time, with or without a diffusion barrier. Electrical measurements are performed at room temperature. From the SEM imaging conducted after permanganate acid etching, formation of spherulites due to heat-treatment is not obvious in neither LDPE nor in XLPE. However, distinctions between LDPE and XLPE in SEM micrographs are evident. From studies with dielectric polarization spectroscopy, it is found that the LDPE samples are less sensitive to heat-treatment in comparison to the XLPE samples while dissipation factor of XLPE samples are influenced by the choice of pressing film used during sample preparation.

  • 2.
    Abächerli, A
    et al.
    International lignin institute, Switzerland.
    Gosselink, R
    Agrotechnology & Food Innovations, The Netherlands.
    Jong, E. de
    Agrotechnology & Food Innovations, The Netherlands.
    Baumberger, S
    French National Institute for Agricultural Research.
    Hortling, B
    KCL.
    Bonini, C
    USB.
    D'Auria, M
    USB.
    Zimbardi, F
    ENEA.
    Barisano, D
    ENEA.
    Duarte, J
    INETI.
    Sena-Martins, G
    INETI.
    Ribeiro, B
    INETI.
    Koukios, E
    NTUA.
    Koullas, D
    NTUA.
    Avgerinos, E
    NTUA.
    Vasile, C
    PPI.
    Cazacu, G
    PPI.
    Mathey, R
    Granit.
    Ghidoni, D
    Granit.
    Gellerstedt, Göran
    KTH, Skolan för kemivetenskap (CHE).
    Li, Jiebing
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik.
    Quintus-Leino, P
    VTT.
    Piepponen, S
    VTT.
    Laine, A
    VTT.
    Koskinen, P
    VTT.
    Gravitis, J
    LSIWC.
    Suren, J
    Bakelite.
    Fasching, M
    Lenzing.
    Intermediary status of the round Robins in the eurolignin network2005Konferansepaper (Fagfellevurdert)
  • 3. Acciaro, Roberta
    et al.
    Aulin, Christian
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik.
    Wågberg, Lars
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Fiberteknologi.
    Lindström, Tom
    Claesson, Per M.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap.
    Varga, Imre
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap.
    Investigation of the formation, structure and release characteristics of self-assembled composite films of cellulose nanofibrils and temperature responsive microgels2011Inngår i: Soft Matter, ISSN 1744-683X, Vol. 7, nr 4, s. 1369-1377Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The possibility of forming self-organized films using charge-stabilized dispersions of cellulose I nanofibrils and microgel beads of poly-(N-isopropylacrylamide-co-acrylic acid) copolymer is presented. The build-up behavior and the properties of the layer-by-layer (LbL)-constructed films were studied using quartz crystal microbalance with dissipation (QCM-D) and ellipsometry. The morphology of the formed films was also characterized using atomic force microscopy (AFM) imaging. The applied methods clearly demonstrated the successful LbL-assembly of the monodisperse microgels and nanofibrils. The in situ QCM-D measurements also revealed that contrary to the polyelectrolyte bound microgel particles, the nanofibrils-bound gel beads preserve their highly swollen state and do not suffer a partial collapse due to the lack of interdigitation of the oppositely charged components. To probe the accessibility of the gel beads in the formed films, the room temperature (similar to 25 degrees C) loading and release of a fluorescent dye (FITC) was also investigated. The incorporation of the cellulose nanofibrils into the multilayer resulted in an open structure that was found easily penetrable for the dye molecules even at constant room temperature, which is in sharp contrast with previously reported systems based on synthetic polyelectrolytes. The amount of dye released from the multilayer films could be fine-tuned with the number of bilayers. Finally, the thermoresponsivity of the films was also shown by triggering the burst release of the loaded dye when the film was collapsed.

  • 4. Adamus, Grazyna
    et al.
    Hakkarainen, Minna
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Höglund, Anders
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Kowalczuk, Marek
    Albertsson, Ann-Christine
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    MALDI-TOF MS Reveals the Molecular Level Structures of Different Hydrophilic-Hydrophobic Polyether-esters2009Inngår i: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 10, nr 6, s. 1540-1546Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Multi- and triblock copolymers based on 1,5-dioxepan-2-one/epsilon-caprolactone (DXO/CL) were investigated by MALDI-TOF MS to determine the influence of copolymer composition and architecture on the molecular structures at the individual chain level. The copolymer compositions, average block lengths, and molecular weights were determined by H-1 and C-13 NMR and by SEC, respectively. The structures of polyether-ester oligomers (linear, cyclic) as well as the chemical structures of their end groups were established on the basis of their MALDI-TOF mass spectra. The mass spectrum of PDXO homopolymer was relatively simple, however, complex mass spectra were obtained in the case of multi- and triblock copolymers and the mass spectra clearly discerned the molecular level effect of copolymer composition and copolymer type.

  • 5. Adekunle, K. F.
    et al.
    Cho, S. W.
    Patzelt, C.
    Blomfeldt, Thomas
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Skrifvars, M.
    Impact and flexural properties of flax fabrics and lyocell fiber reinforced bio-based thermoset for automotive and structural applications2012Inngår i: ECCM 2012 - Composites at Venice, Proceedings of the 15th European Conference on Composite Materials, European Conference on Composite Materials, ECCM , 2012Konferansepaper (Fagfellevurdert)
    Abstract [en]

    A bio-based thermoset resin was reinforced with flax fabrics and Lyocell fiber. The effect of different weave architecture was studied with four flax fabrics with different architecture: plain, twill (two different types) and dobby. The effect of the outer ply thickness was studied and characterized with flexural and impact testing. Composites manufactured with plain weave reinforcement had the best mechanical properties. The tensile strength, tensile modulus, flexural strength, flexural modulus and impact strength was 280 MPa, 32 GPa, 250 MPa, 25 GPa and 75 kJ/m2 respectively.

  • 6. Adekunle, Kayode
    et al.
    Cho, Sung-Woo
    Patzelt, Christian
    Blomfeldt, Thomas
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymera material.
    Skrifvars, Mikael
    Impact and flexural properties of flax fabrics and Lyocell fiber-reinforced bio-based thermoset2011Inngår i: Journal of reinforced plastics and composites (Print), ISSN 0731-6844, E-ISSN 1530-7964, Vol. 30, nr 8, s. 685-697Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A bio-based thermoset resin was reinforced with flax fabrics and Lyocell fiber. The effect of different weave architectures was studied with four flax fabrics with different architectures: plain, twill (two different types), and dobby. The effect of the outer ply thickness was studied and characterized with flexural and impact testing. Composites manufactured with plain weave reinforcement had the best mechanical properties. The tensile strength, tensile modulus, flexural strength, flexural modulus, and impact strength were 280MPa, 32GPa, 250MPa, 25GPa, and 75 kJ/m (2), respectively. Reinforcements with twill-weave architecture did not impart appreciable flexural strength or flexural modulus even when the outer thickness was increased. Plain- and dobby (basket woven style)-weave architectures gave better reinforcing effects and the flexural properties increased with an increase in outer thickness. Water absorption properties of the composites were studied and it was observed that the hybridization with Lyocell fiber reduced the water uptake. Field-emission scanning electron microscopy was used to study the micro-structural properties of the composites.

  • 7.
    Adler, Jeanette
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik.
    Film Formation and Surface Tension Studies of Powder Coatings2005Independent thesis Basic level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    In industrial use of paint systems a swift processing is crucial. Another very important issue is to improve the quality of the final coating. This report investigates the film formation process of powder coatings, specially the spreading of individual powder particles. The obtained results can be used to understand and control the film formation process. In this way the desired levelling can be achieved and thus the desired gloss or other surface characteristics that may be required. This means that the method could be used when evaluating different polymer and additive combinations that could be used to change film formation behaviour or curing time for powder coating systems to suit various substrates. It makes it possible to avoid and minimize different surface defects as orange peel or cratering in the powder coated film.

    We used a reflection optical microscope to better understand the film formation process and especially the spreading of a powder melt on surfaces with various surface energies. The obtained data were: the particle diameter, the area, area ratio and the contact angle of the powder particle as a function of time and temperature. This information can be used to derive the surface tension of any powder melt.

    In this report we evaluate the dependencies of temperature, heat rate and surface energy for powder coatings on different substrates. The method provides information that can be used to optimize the film formation of a specific powder coating/substrate combination. This method can be used to evaluate the powder spreading and levelling on different substrates from a surface tension point of view.

    We found, as expected, that the powder flows out on a hydrophilic surface and is inhibited by a hydrophobic. The increase of the area ratio on a hydrophilic surface was about five times as the initial area coverage and on a hydrophobic surface only two times the initial area coverage. The contact angle between the melted powder particle on the different surface types could be calculated. The melt surface tension could be calculated since three substrates surfaces with various surface energies were used. The melt surface tension was found to be about 18.5 mN/m.

  • 8.
    Adolfsson, Karin H.
    et al.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Hassanzadeh, Salman
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Hakkarainen, Minna
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Valorization of cellulose and waste paper to graphene oxide quantum dots2015Inngår i: RSC Advances, ISSN 2046-2069, E-ISSN 2046-2069, Vol. 5, nr 34, s. 26550-26558Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Biobased graphene oxide quantum dots (GOQD) were derived from cellulose via carbon nanospheres (CN) as intermediate products. Solid CN were synthesized from cellulose through microwave-assisted hydrothermal degradation of alpha-cellulose with H2SO4 as a catalyst at 160 degrees C. The obtained CN were further utilized for the synthesis of GOQD by a two-step reaction including 30 minutes of sonication followed by heating at 90 degrees C under O-rich acidic conditions (HNO3). This process broke down the 3D CN to 2D GOQD. The size of the synthesized GOQD was controlled by the heating time, reaching a dot diameter of 3.3 nm and 1.2 nm after 30 and 60 minutes of heating, respectively. The synthesis process and products were characterized by multiple analytical techniques including FTIR, TGA, SEM, TEM, XPS, XRD, BET, DLS and AFM. Interesting optical properties in aqueous solutions were demonstrated by UV/Vis and fluorescence spectroscopy. Finally we demonstrated that corresponding GOQD can be synthesized from waste paper. This production route thus uses renewable and cheap starting materials and relatively mild synthesis procedures leads to instant nanometric production of 2D dots. In addition it enables recycling of low quality waste to value-added products.

  • 9.
    Adolfsson, Karin H.
    et al.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi. Sch Chem Sci & Engn, Stockholm, Sweden..
    Hassanzadeh, Salman
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi. Sch Chem Sci & Engn, Stockholm, Sweden..
    Hakkarainen, Minna
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi. Sch Chem Sci & Engn, Stockholm, Sweden..
    Value-added carbon products attained through microwave assisted hydrothermal treatment of cellulose and waste paper2016Inngår i: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 251Artikkel i tidsskrift (Annet vitenskapelig)
  • 10.
    Adolfsson, Karin H.
    et al.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi, Polymerteknologi.
    Xie, L.
    Hassanzadeh, Salman
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi, Polymerteknologi.
    Pettersson, Torbjörn
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi, Fiberteknologi.
    Hakkarainen, Minna
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi, Polymerteknologi.
    Zero-Dimensional and Highly Oxygenated Graphene Oxide for Multifunctional Poly(lactic acid) Bionanocomposites2016Inngår i: ACS Sustainable Chemistry & Engineering, ISSN 2168-0485, Vol. 4, nr 10, s. 5618-5631Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The unique strengths of 2D graphene oxide nanosheets (GONSs) in polymer composites are thwarted by nanosheet agglomeration due to strong intersheet attractions. Here, we reveal that shrinking the planar size to 0D graphene oxide quantum dots (GOQDs), together with the intercalation of rich oxygen functional groups, reduces filler aggregation and enhances interfacial interactions with the host polymer. With poly(lactic acid) (PLA) as a model matrix, atomic force microscopy colloidal probe measurements illustrated that a triple increase in adhesion force to PLA was achieved for GOQDs (234.8 nN) compared to GONSs (80.4 nN), accounting for the excellent exfoliation and dispersion of GOQDs in PLA, in contrast to the notable agglomeration of GONSs. Although present at trace amount (0.05 wt %), GOQDs made a significant contribution to nucleation activity, mechanical strength and ductility, and gas barrier properties of PLA, which contrasted the inferior efficacy of GONSs, accompanied by clear distinction in film transparency (91% and 50%, respectively). Moreover, the GOQDs with higher hydrophilicity accelerated the degradation of PLA by enhancing water erosion, while the GONSs with large sheet surfaces gave a higher hydrolytic resistance. Our findings provide conceptual insights into the importance of the dimensionality and surface chemistry of GO nanostructures in the promising field of bionanocomposites integrating high strength and multifunction (e.g., enhanced transparency, degradation and gas barrier).

  • 11.
    Agfors, Gunnar
    et al.
    Ledamot av IVA.
    Albertsson, Ann-Christine
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik.
    Grenthe, Ingmar
    KTH, Skolan för kemivetenskap (CHE), Kemi, Oorganisk kemi.
    Wågberg, Lars
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik.
    Ödberg, Lars
    et, al
    KEMI: den gränslösa vetenskapen2011Bok (Annet (populærvitenskap, debatt, mm))
    Abstract [sv]

    Kemi – handlar inte det bara om farliga ämnen och onödiga tillsatser? Det är kanske bildenmånga har av kemi, men faktum är att utan kemi skulle vi inte ha det höga välstånd vi har i dag.Tack vare kemisk kunskap har vi tillgång till läkemedel som botar sjukdomar och lindrar smärta– med hjälp av syntetiska antibiotika kan infektionssjukdomar som tidigare var dödliga botas,magsår kan behandlas utan dyra och plågsamma operationer och många cancerformer kanframgångsrikt behandlas med syntetiska preparat. Konstgödsel och medel som hindrar skadeinsektergör att skördar kan ökas och svälten i världen därigenom begränsas. Tack vare kemin harvi även tillgång till alla de material vi behöver för att tillverka allt från kläder, rengöringsprodukteroch kosmetika till bilar, TV-apparater och reservdelar till kroppen. Det är genom kemisk syntes vikan framställa dessa och alla de övriga produkter vi behöver för vårt dagliga liv och det är keminsom visar vägen till hållbar produktion som utnyttjar förnybara råvaror och ger minimala mängderavfall. Kemisk kunskap är också oumbärlig för utveckling av nanoteknik och medicinskdiagnostik och andra till kemin angränsande områden. Kemin bidrar alltså till att finna lösningartill många av de komplexa globala problem vi står inför: hälsa, klimat, brist på råvaror, utnyttjandetav nya energikällor och tillgång till livsmedel för att föda jordens ökande befolkning.

    DET ÄR OM ALLT DETTA DEN HÄR BOKEN HANDLAR.

  • 12. Aguirre, Miren
    et al.
    Johansson Salazar-Sandoval, Eric
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik. SP Technical Research Institute of Sweden, Sweden.
    Johansson, Mats
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik.
    Ahniyaz, Anwar
    Paulis, Maria
    Ramon Leiza, Jose
    Hybrid acrylic/CeO2 nanocomposites using hydrophilic, spherical and high aspect ratio CeO2 nanoparticles2014Inngår i: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 2, nr 47, s. 20280-20287Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A dispersion of CeO2 nanoparticles and nanorods stabilized with nitrilotriacetic acid (NTA) and a 4,4'-azobis(4-cyanovaleric acid) (V-501) initiator has been used to initiate the emulsion polymerization of acrylic monomers, yielding stable hybrid CeO2 nanoparticle-nanorod/polyacrylate latexes for the first time. Films cast from these hybrid latexes are transparent due to the very homogenous distribution of the polymer compatibilized CeO2. Furthermore, it has been proven that the UV-Vis absorption capacity of the hybrid latexes is enhanced with the incorporation of the nanorods.

  • 13.
    Ajmal Khan, Muhammad
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Raza, Rizwan
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Bohn Lima, Raquel
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik. KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik.
    Chaudhry, M. Asharf
    Ahmed, E.
    Abbas, Ghazanfar
    Comparative study of the nano-composite electrolytes based on samaria-doped ceria for low temperature solid oxide fuel cells (LT-SOFCs)2013Inngår i: International journal of hydrogen energy, ISSN 0360-3199, E-ISSN 1879-3487, Vol. 38, nr 36, s. 16524-16531Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Ceria-based electrolyte materials have great potential in low and intermediate temperature solid oxide fuel cell applications. In the present study, three types of ceria-based nanocomposite electrolytes (LNK-SDC, LN-SDC and NK-SDC) were synthesized. One-step co-precipitation method was adopted and different techniques were applied to characterize the obtained ceria-based nano-composite electrolyte materials. TGA, XRD and SEM were used to analyze the thermal effect, crystal structure and morphology of the materials. Cubic fluorite structures have been observed in all composite electrolytes. Furthermore, the crystallite sizes of the LN-SDC, NK-SDC, LNK-SDC were calculated by Scherrer formula and found to be in the range 20 nm, 21 nm and 19 nm, respectively. These values emphasize a good agreement with the SEM results. The ionic conductivities were measured using EIS (Electrochemical Impedance Spectroscopy) with two-probe method and the activation energies were also calculated using Arrhenius plot. The maximum power density was achieved 484 mW/cm(2) of LNK-SDC electrolyte at 570 degrees C using the LiCuZnNi oxide electrodes.

  • 14.
    Akhlaghi, Shahin
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Degradation of acrylonitrile butadiene rubber and fluoroelastomers in rapeseed biodiesel and hydrogenated vegetable oil2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Biodiesel and hydrotreated vegetable oil (HVO) are currently viewed by the transportation sector as the most viable alternative fuels to replace petroleum-based fuels. The use of biodiesel has, however, been limited by the deteriorative effect of biodiesel on rubber parts in automobile fuel systems. This work therefore aimed at investigating the degradation of acrylonitrile butadiene rubber (NBR) and fluoroelastomers (FKM) on exposure to biodiesel and HVO at different temperatures and oxygen concentrations in an automated ageing equipment and a high-pressure autoclave. The oxidation of biodiesel at 80 °C was promoted by an increase in the oxygen partial pressure, resulting in the formation of larger amounts of hydroperoxides and acids in the fuel. The fatty acid methyl esters of the biodiesel oxidized less at 150 °C on autoclave aging, because the termination reactions between alkyl and alkylperoxyl radicals dominated over the initiation reactions. HVO consists of saturated hydrocarbons, and remained intact during the exposure. The NBR absorbed a large amount of biodiesel due to fuel-driven internal cavitation in the rubber, and the uptake increased with increasing oxygen partial pressure due to the increase in concentration of oxidation products of the biodiesel. The absence of a tan δ peak (dynamical mechanical measurements) of the bound rubber and the appearance of carbon black particles devoid of rubber suggested that the cavitation was caused by the detachment of bound rubber from particle surfaces. A significant decrease in the strain-at-break and in the Payne-effect amplitude of NBR exposed to biodiesel was explained as being due to the damage caused by biodiesel to the rubber-carbon-black network. During the high-temperature autoclave ageing, the NBR swelled less in biodiesel, and showed a small decrease in the strain-at-break due to the cleavage of rubber chains. The degradation of NBR in the absence of carbon black was due only to biodiesel-promoted oxidative crosslinking. The zinc cations released by the dissolution of zinc oxide particles in biodiesel promoted reduction reactions in the acrylonitrile part of the NBR. Heat-treated star-shaped ZnO particles dissolved more slowly in biodiesel than the commercial ZnO nanoparticles due to the elimination of inter-particle porosity by heat treatment. The fuel sorption was hindered in HVO-exposed NBR by the steric constraints of the bulky HVO molecules. The extensibility of NBR decreased only slightly after exposure to HVO, due to the migration of plasticizer from the rubber. The bisphenol-cured FKM co- and terpolymer swelled more than the peroxide-cured GFLT-type FKM in biodiesel due to the chain cleavage caused by the attack of biodiesel on the double bonds formed during the bisphenol curing. The FKM rubbers absorbed biodiesel faster, and to a greater extent, with increasing oxygen concentration. It is suggested that the extensive biodiesel uptake and the decrease in the strain-at-break and Young’s modulus of the FKM terpolymer was due to dehydrofluorination of the rubber by the coordination complexes of biodiesel and magnesium oxide and calcium hydroxide particles. An increase in the CH2-concentration of the extracted FKM rubbers suggested that biodiesel was grafted onto the FKM at the unsaturated sites resulting from dehydrofluorination.

  • 15.
    Akhlaghi, Shahin
    et al.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Amir Masoud, Pourrahimi
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Christian, Sjöstedt
    Martin, Bellander
    Mikael S., Hedenqvist
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Ulf W., Gedde
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Degradation of fluoroelastomers in rapeseed biodiesel at different oxygen concentrations2017Inngår i: Polymer degradation and stability, ISSN 0141-3910, E-ISSN 1873-2321, Vol. 136, s. 10-19Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The degradation of fluoroelastomers (FKM) based on different monomers, additives and curing systems was studied after exposure to rapeseed biodiesel at 100 °C and different oxygen partial pressures. The sorption of fuel in the carbon black-filled FKM terpolymer was promoted by the fuel-driven cavitation in the rubber. The bisphenol-cured rubbers swelled more in biodiesel than the peroxide-cured FKM, presumably due to the chain cleavage caused by the attack of biodiesel on the double bonds formed during the bisphenol curing. With any of the selected types of monomer, the FKM rubbers absorbed biodiesel faster and to a greater extent with increasing oxygen partial pressure due to the increase in concentration of the oxidation products of biodiesel. Water-assisted complexation of biodiesel on magnesium oxide and calcium hydroxide particles led to dehydrofluorination of FKM, resulting in an extensive fuel uptake and a decrease in the strain-at-break and the Young's modulus of the rubbers. An increase in the CH2-concentration determined by infrared spectroscopy, and the appearance of biodiesel flakes in scanning electron micrographs of the extracted rubbers, were explained as being due to the presence of insoluble biodiesel grafted onto FKM on the unsaturated sites resulting from dehydrofluorination. The extensibility of the GFLT-type FKM was the least affected on exposure to biodiesel because this rubber contained less unsaturation and metal oxide/hydroxide particles.

  • 16.
    Akhlaghi, Shahin
    et al.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi, Polymera material. Scania CV AB, Sweden.
    Gedde, Ulf W.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi, Polymera material.
    Hedenqvist, Mikael S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi, Polymera material.
    Brana, Maria T. Conde
    Bellander, Martin
    Deterioration of automotive rubbers in liquid biofuels: A review2015Inngår i: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 43, s. 1238-1248Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Concerns over the fast depletion of fossil fuels, environmental issues and stringent legislation associated with petroleum-based fuels have triggered a shift to bio-based fuels, as an alternative to meet the growing energy demand in the transportation sector. However, since conventional automobile fuel systems are adapted to petroleum-based fuels, switching to biofuels causes a severe deterioration in the performance of currently used rubber components. The degradation of the rubber materials in biofuels is complicated by the presence of different additives in biofuels and rubber compounds, by oxidation of biofuels and by the effects of thermomechanical loadings in the engine. This paper presents a comprehensive review of the effects of different types of biofuels, particularly biodiesel and bioethanol, on the physical, mechanical, morphological and thermal properties of elastomers under different exposure conditions. In addition, the literature data available on the variation of rubbers' resistance to biofuels with the changes in their monomer type and composition, cure system and additives content was also studied. The review essentially focuses on the compatibility of biofuels with acrylonitrile butadiene rubber, fluoroelastomers, polychloroprene rubber and silicon rubber, as the most commonly used automotive rubbers coming into contact with fuels during their service. The knowledge summarized in this study can help to develop a guideline on the selection of rubber for automotive parts designed to withstand biofuels.

  • 17.
    Akhlaghi, Shahin
    et al.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Hedenqvist, Mikael S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Brana, M. T. Conde
    Bellander, M.
    Gedde, Ulf W.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Deterioration of acrylonitrile butadiene rubber in rapeseed biodiesel2015Inngår i: Polymer degradation and stability, ISSN 0141-3910, E-ISSN 1873-2321, Vol. 111, s. 211-222Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The deterioration of acrylonitrile butadiene rubber (NBR) exposed to rapeseed biodiesel at 90 degrees C was studied. The oxidation of biodiesel and NBR during ageing was monitored by H-1 NMR and infrared spectroscopy, HPLC and titration methods. The oxidation of biodiesel was impeded in the presence of NBR, but promoted in biodiesel-exposed rubber. This was explained as being due to the migration of stabilizer from the rubber to biodiesel, the diffusion of dissolved oxygen from biodiesel into NBR and the absorption of oxidation precursors of biodiesel by the rubber. The resemblance between the anomalous sorption kinetics of biodiesel in NBR and the equilibrium benzene uptake by the aged rubbers revealed that biodiesel caused a network defect in NBR, resulting in a gradual increase in the equilibrium swelling. The cleavage of crosslinks was implausible since the Young's modulus of the rubber at low strains, disregarding an initial decrease, increased with increasing exposure time. The appearance of 'naked' carbon black particles in the scanning electron micrographs of the aged rubbers and a drastic decrease in the strain-at-break of NBR after exposure to biodiesel suggests that internal cavitation was caused by the attack of biodiesel on the acrylonitrile units of NBR.

  • 18.
    Akhlaghi, Shahin
    et al.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Pourrahimi, A. M.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Christian, Sjöstedt
    Martin, Bellander
    Mikael S., Hedenqvist
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Ulf W., Gedde
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Effects of ageing conditions on degradation of acrylonitrile butadiene rubber filled with heat-treated ZnO star-shaped particles in rapeseed biodiesel2017Inngår i: Polymer degradation and stability, ISSN 0141-3910, E-ISSN 1873-2321Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The degradation of acrylonitrile butadiene rubber (NBR) after exposure to biodiesel at different oxygen partial pressures in an automated ageing equipment at 80 °C, and in a high-pressure autoclave at 150 °C was studied. The oxidation of biodiesel was promoted by an increase in oxygen concentration, resulting in a larger uptake of fuel in the rubber due to internal cavitation, a greater decrease in the strain-at-break of NBR due to the coalescence of cavity, and a faster increase in the crosslinking density and carbonyl index due to the promotion of the oxidation of NBR. During the high-temperature autoclave ageing, less fuel was absorbed in the rubber, because the formation of hydroperoxides and acids was impeded. The extensibility of NBR aged in the autoclave decreased only slightly due to the cleavage of rubber chains by the biodiesel attack. The degradation of NBR in the absence of carbon black was explained as being due to oxidative crosslinking. The dissolution of ZnO crystals in the acidic components of biodiesel was retarded by removing the inter-particle porosity and surface defects through heat treating star-shaped ZnO particles. The rubber containing heat-treated ZnO particles swelled less in biodiesel than a NBR filled with commercial ZnO nanoparticles, and showed a smaller decrease in the strain-at-break and less oxidative crosslinking.

  • 19.
    Akhlaghi, Shahin
    et al.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi, Polymera material.
    Pourrahimi, Amir Masoud
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi, Polymera material.
    Hedenqvist, Mikael
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi, Polymera material.
    Sjöstedt, C.
    Bellander, M.
    Gedde, Ulf
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi, Polymera material.
    Degradation of carbon-black-filled acrylonitrile butadiene rubber in alternative fuels: Transesterified and hydrotreated vegetable oils2016Inngår i: Polymer degradation and stability, ISSN 0141-3910, E-ISSN 1873-2321, Vol. 123, s. 69-79Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The deterioration of acrylonitrile butadiene rubber (NBR), a common sealing material in automobile fuel systems, when exposed to rapeseed biodiesel and hydrotreated vegetable oil (HVO) was studied. The fuel sorption was hindered in HVO-exposed rubber by the steric constraints of bulky HVO molecules, but it was promoted in biodiesel-exposed rubber by fuel-driven cavitation in the NBR and by the increase in diffusivity of biodiesel after oxidation. The absence of a tan δ peak of the bound rubber and the appearance of carbon black particles devoid of rubber suggested that the cavitation was made possible in biodiesel-aged rubber by the detachment of bound rubber from particle surfaces. The HVO-exposed NBR showed a small decrease in strain-at-break due to the migration of plasticizer from the rubber, and a small increase in the Young’s modulus due to oxidative crosslinking. A drastic decrease in extensibility and Payne-effect amplitude of NBR on exposure to biodiesel was explained as being due to the damage caused by biodiesel to the continuous network of bound rubber-carbon black. A decrease in the ZnO crystal size with increasing exposure time suggested that the particles are gradually dissolved in the acidic components of oxidized biodiesel. The Zn2+ cations released from the dissolution of ZnO particles in biodiesel promoted the hydrolysis of the nitrile groups of NBR.

  • 20.
    Albertsson, A-C.
    et al.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Andersson, S-O.
    Karlsson, S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    The mechanism of biodegradation of polyethylene1987Inngår i: Polymer degradation and stability, ISSN 0141-3910, E-ISSN 1873-2321, Vol. 18, s. 73-87Artikkel i tidsskrift (Fagfellevurdert)
  • 21. Albertsson, A-C.
    et al.
    Barenstedt, C.
    Karlsson, S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Degradation of enhanced environmentally degradable polyethylene in biological aqueous media: mechanisms during the first stages1994Inngår i: Journal of Applied Polymer Science, ISSN 0021-8995, E-ISSN 1097-4628, Vol. 51, nr 6, s. 1097-1105Artikkel i tidsskrift (Fagfellevurdert)
  • 22. Albertsson, A-C.
    et al.
    Barenstedt, C.
    Karlsson, S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Increased biodegradation of a low-density polyethylene (LDPE) matrix in starch-filled LDPE materials1993Inngår i: Journal of environmental polymer degradation, ISSN 1064-7546, E-ISSN 1572-8900, Vol. 1, nr 4, s. 241-245Artikkel i tidsskrift (Fagfellevurdert)
  • 23. Albertsson, A-C.
    et al.
    Barenstedt, C.
    Karlsson, S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Solid-phase extraction and gas chromatographic-mass spectrometric identification of degradation products from enhanced environmentally degradable polyethylene1995Inngår i: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 690, nr 2, s. 207-217Artikkel i tidsskrift (Fagfellevurdert)
  • 24. Albertsson, A-C.
    et al.
    Barenstedt, C.
    Karlsson, S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Susceptibility of enhanced environmentally degradable polyethylene to thermal and photo-oxidation1992Inngår i: Polymer degradation and stability, ISSN 0141-3910, E-ISSN 1873-2321, Vol. 37, nr 2, s. 163-171Artikkel i tidsskrift (Fagfellevurdert)
  • 25. Albertsson, A-C.
    et al.
    Barenstedt, C.
    Karlsson, S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Lindberg, T.
    Degradation product pattern and morphology changes as means to differentiate abiotically and biotically aged degradable polyethylene1995Inngår i: Polymer, ISSN 0032-3861, E-ISSN 1873-2291, Vol. 36, nr 16, s. 3075-83Artikkel i tidsskrift (Fagfellevurdert)
  • 26. Albertsson, A-C.
    et al.
    Griffin, G. J. L.
    Karlsson, S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Nishimoto, K.
    Watanabe, Y.
    Spectroscopic and mechanical changes in irradiated starch-filled LDPE1994Inngår i: Polymer degradation and stability, ISSN 0141-3910, E-ISSN 1873-2321, Vol. 45, nr 2, s. 173-178Artikkel i tidsskrift (Fagfellevurdert)
  • 27. Albertsson, A-C.
    et al.
    Karlsson, S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Abiotic degradation products from enhanced environmentally degradable polyethylene1994Inngår i: Acta Polymerica, ISSN 0323-7648, E-ISSN 1521-4044, Vol. 45, nr 2, s. 97-103Artikkel i tidsskrift (Fagfellevurdert)
  • 28. Albertsson, A-C.
    et al.
    Karlsson, S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Aspects of biodeterioration of inert and degradable polymers1993Inngår i: International Biodeterioration & Biodegradation, ISSN 0964-8305, E-ISSN 1879-0208, Vol. 31, nr 3, s. 161-170Artikkel i tidsskrift (Fagfellevurdert)
  • 29. Albertsson, A-C.
    et al.
    Karlsson, S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Biodegradable polymers1992Inngår i: Comprehensive Polymer Science, Supplement Series, Midland, Michigan: Pergamon Press, 1992, s. 285-Kapittel i bok, del av antologi (Fagfellevurdert)
  • 30. Albertsson, A-C.
    et al.
    Karlsson, S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Biodegradation and testmethods for environmental and biomedical applications of polymers1990Inngår i: Degradable Materials, Boca Raton: CRC Press, 1990, s. 263-Kapittel i bok, del av antologi (Fagfellevurdert)
  • 31. Albertsson, A-C.
    et al.
    Karlsson, S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Chemistry and biochemistry of polymer biodegradation1994Inngår i: Chemistry and Technology of Biodegradable Polymers / [ed] G.J.L. Griffin, London, England: Blackie Academic & Professional , 1994, s. 7-17Kapittel i bok, del av antologi (Fagfellevurdert)
  • 32. Albertsson, A-C.
    et al.
    Karlsson, S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Chromatographic fingerprinting as a means to predict degradation mechanisms1996Inngår i: Journal of environmental polymer degradation, ISSN 1064-7546, E-ISSN 1572-8900, Vol. 4, nr 1, s. 51-3Artikkel i tidsskrift (Fagfellevurdert)
  • 33. Albertsson, A-C.
    et al.
    Karlsson, S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Controlled degradation by artificial and biological processes1996Inngår i: Macromol. Design of Polymeric Materials, Marcel Dekker, 1996, s. 54-Kapittel i bok, del av antologi (Fagfellevurdert)
  • 34. Albertsson, A-C.
    et al.
    Karlsson, S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Degradable polyethylene-starch complex1991Inngår i: Makromolekulare Chemie, Macromolecular Symposia, Vol. 48-49, nr Eur. Polym. Fed. Symp. Polym. Mater., 3rd, 1990, s. 395-402Artikkel i tidsskrift (Fagfellevurdert)
  • 35. Albertsson, A-C.
    et al.
    Karlsson, S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Degradable Polymers1996Inngår i: The Polymeric Materials Encyclopedia: Synthesis, Properties and Applications / [ed] J. C. Salamone, Boca Raton, USA: CRC Press, 1996, s. 150-Kapittel i bok, del av antologi (Fagfellevurdert)
  • 36. Albertsson, A-C.
    et al.
    Karlsson, S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Degradable polymers for the future1995Inngår i: Acta Polymerica, ISSN 0323-7648, E-ISSN 1521-4044, Vol. 46, nr 2, s. 114-123Artikkel i tidsskrift (Fagfellevurdert)
  • 37. Albertsson, A-C.
    et al.
    Karlsson, S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Environment-adaptable polymers1993Inngår i: Polymer degradation and stability, ISSN 0141-3910, E-ISSN 1873-2321, Vol. 41, nr 3, s. 345-349Artikkel i tidsskrift (Fagfellevurdert)
  • 38. Albertsson, A-C.
    et al.
    Karlsson, S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Increased biodegradation of LDPE-matrix in starch-filled LDPE materials1992Inngår i: Materials Science and Engineering, Vol. 67, s. 296-297Artikkel i tidsskrift (Fagfellevurdert)
  • 39. Albertsson, A-C.
    et al.
    Karlsson, S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Macromolecular architecture-nature as model for degradable polymers1996Inngår i: Journal of Macromolecular Science, Part A: Pure and Applied Chemistry, Vol. 33, nr 10, s. 1565-1570Artikkel i tidsskrift (Fagfellevurdert)
  • 40. Albertsson, A-C.
    et al.
    Karlsson, S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    New tools for analyzing degradation1995Inngår i: Macromolecular Symposia, ISSN 1022-1360, E-ISSN 1521-3900, Vol. 98, nr 35th IUPAC International Symposium on Macromolecules, 1995, s. 797-801Artikkel i tidsskrift (Fagfellevurdert)
  • 41. Albertsson, A-C.
    et al.
    Karlsson, S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Polyethylene degradation and degradation products1990Inngår i: Agricultural and Synthetic Polymers: Biodegradability and Utilization, American Chemical Society (ACS), 1990, Vol. 433, nr Agricultural & Synthetic Polymers, s. 60-64Kapittel i bok, del av antologi (Fagfellevurdert)
  • 42. Albertsson, A-C.
    et al.
    Karlsson, S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    The Influence of Biotic and Abiotic Environments on the Degradation of Polyethylene.1990Inngår i: Progress in polymer science, ISSN 0079-6700, E-ISSN 1873-1619, Vol. 15, nr 2, s. 177-192Artikkel i tidsskrift (Fagfellevurdert)
  • 43. Albertsson, A-C.
    et al.
    Sares, C.
    Karlsson, S.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Increased biodegradation of low-density polyethylene (LDPE) with nonionic surfactant1993Inngår i: Acta Polymerica, ISSN 0323-7648, E-ISSN 1521-4044, Vol. 44, nr 5, s. 243-246Artikkel i tidsskrift (Fagfellevurdert)
  • 44.
    Albertsson, Ann-Christine
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Design of green materials by building-in a controlled behavior2014Inngår i: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 247Artikkel i tidsskrift (Annet vitenskapelig)
  • 45.
    Albertsson, Ann-Christine
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    From design and synthesis to advanced properties and sustainable polymeric materials2017Inngår i: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 253Artikkel i tidsskrift (Annet vitenskapelig)
  • 46.
    Albertsson, Ann-Christine
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Frontiers in Biomacromolecules: Functional Materials from Nature2012Inngår i: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 13, nr 12, s. 3901-3901Artikkel i tidsskrift (Annet vitenskapelig)
  • 47.
    Albertsson, Ann-Christine
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Polymerteknologi.
    Long-Term Properties of Polyolefins2004Collection/Antologi (Fagfellevurdert)
    Abstract [en]

    We dedicate the current volume entitled "Long-Term Properties of Polyolefins"to Professor Kausch on his 25th anniversary as editor of Advances in PolymerScience. Professor Kausch pioneered the work on molecular effects in thefracture of polymers. This is beautifully summarized in his books on polymerfracture. Professor Kausch is also the perfect gentleman - always eager to helpnewcomers to make their entrance into the scientific community and to assisthis colleagues in their work and accomplishments. With his work, ProfessorKausch has demonstrated the importance of "source science" - to present newdata - and to present reviews of previously published material. This book ispresented in the spirit of Professor Kausch, namely showing a good selection ofdata and explaining what they mean.The main focus of this book is the relation between structure and propertiesand the trend towards better quality and reproducibility. The first chapterdescribes the metallocene polymerisation catalysts and their possihility notonly of tailoring polymer properties but also of manufacturing entirely newmaterials. Due to improved control of microstructure, it will also be possible toproduce specialty polyolefins which could compete with non-olefinic polymers.The next chapter shows how in each new development step catalyst and processinnovations have gone hand in hand and how the control over polymer structureand the ability to tailor material properties has increased. For a betterunderstanding of properties and behaviour, the basic of morphology is fundamentaland is described in chapter three, followed by chapter four aboutfracture properties and microdeformation behaviour. Promising model systemsfor the investigations of the relations between crack-tip deformation, fractureand molecular structure are also presented. Chapter five gives an overviewof stabilization of polyethylene crucial for long-term properties. Two mainapproaches have been used; the first advocates the use of biological antioxidants,and the second relies on the use of reactive antioxidants that are chemicallyattached onto the polymer backbone for greater performance and safety.Chemiluminescence is presented as a too1 for studying the initial stages inoxidative degradation and is explained in chapter six. However, for many years,tailor-made structures specially designed for environmental degradation havealso been a reality. One of the key questions for successhl development and useof environmentally degradable polymers is the interaction between the degradationprodncts and nature and this is illustrated in chapter seven. The developmentof chromatographic methods and use of chromatographic fingerprintinggives not only degradation products bnt also information about degradationmechanisms as well as interaction between the polymer and different environments.The obstacles and possibilities for recycling of polyolefins are discussedin chapter eigbt with special emphasis on analytical methods useful in theqnality concept. It is also shown how recycled material could be a valuable resourcein the Future together with renewable resources. Finally, chapter ninegives examples of existing as we11 as emerging techniques of surface modificationof polyethylene.These chapters together will hopefuiiy inspire to a new generation of polyethyleneby mimicking nature and use of new molecular architecture, newmorphology and also "activated" additives in microdomains, with even morereproducible properties within oarrow limits and with predetermined lifetimes.

  • 48.
    Albertsson, Ann-Christine
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    POLY 344-Renewable green polymers2007Inngår i: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 234Artikkel i tidsskrift (Annet vitenskapelig)
  • 49.
    Albertsson, Ann-Christine
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Take advantage of what Nature creates and utilize biomass2017Inngår i: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 253Artikkel i tidsskrift (Annet vitenskapelig)
  • 50.
    Albertsson, Ann-Christine
    et al.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik.
    David, G.
    Strandberg, C.
    Bilba, D.
    Paduraru, C.
    Synthesis of core-shell structured carboxylated microparticles with a straightforward procedure and their evaluation as a polymer support2005Inngår i: Journal of Polymer Science Part A: Polymer Chemistry, ISSN 0887-624X, E-ISSN 1099-0518, Vol. 43, nr 23, s. 5889-5898Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Poly(trimethylolpropane trimethacrylate) microspheres with a narrow size distribution were obtained by precipitation polymerization. They were subsequently modified by surface grafting with acrylic acid in a polar ethanol-water reaction medium, without stabilizer, yielding core-shell particles with diameters in the micrometer range. The resulting polymeric material was characterized by SEM and potentiometric titration, FTIR spectroscopy, and thermal analysis. It was shown that the particle characteristics (size, size distribution, and functionality) obtained by this straightforward procedure can be controlled by modifying the synthesis parameters (monomer concentration, agitation rate, and temperature). The high functionality, the chemical and physico-mechanical stability, as well as the possibility to control the performances of the resulting polymeric materials by synthesis allow its applications in various areas. Envisaging separation and catalysis domains, Cu(II), Cd(II), and Cr(III) uptake capacity from aqueous solutions was investigated under noncompetitive conditions as a function of synthesized particle functionality, time, and pH range. It was also found that the addition of the carboxylated. microparticles to polyethylene stabilized with alpha-tocopherol improved the thermo-oxidative behaviour of the polymeric material.

1234567 1 - 50 of 2737
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