kth.sePublikationer
Ändra sökning
Avgränsa sökresultatet
1 - 16 av 16
RefereraExporteraLänk till träfflistan
Permanent länk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Träffar per sida
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
  • Disputationsdatum (tidigaste först)
  • Disputationsdatum (senaste först)
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
  • Disputationsdatum (tidigaste först)
  • Disputationsdatum (senaste först)
Markera
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 1.
    Chen, Pan
    et al.
    Beijing Inst Technol, Sch Mat Sci & Engn, Beijing Engn Res Ctr Cellulose & Its Derivat, Beijing 100081, Peoples R China..
    Lo Re, Giada
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Biokompositer. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. Chalmers Univ Technol, Dept Ind & Mat Sci, SE-41296 Gothenburg, Sweden..
    Berglund, Lars
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Biokompositer. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Wohlert, Jakob
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Biokompositer.
    Surface modification effects on nanocellulose - molecular dynamics simulations using umbrella sampling and computational alchemy2020Ingår i: Journal of Materials Chemistry A, ISSN 2050-7488, E-ISSN 2050-7496, Vol. 8, nr 44, s. 23617-23627Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Topochemical modification of nanocellulose particles, in particular acetylation, is commonly used to reduce hygroscopicity and improve their dispersibility in non-polar polymers. Despite enormous experimental efforts on cellulose surface modification, there is currently no comprehensive model which considers both (a) the specific interactions between nanocellulose particles and the surrounding liquid or polymer matrix, and (b) the interactions between the particles themselves. The second mechanism is therefore frequently ignored. The present approach is based on atomistic molecular dynamics (MD) simulations, where computational alchemy is used to calculate the changes in interactions between nanocellulose and the surrounding medium (liquid or polymer) upon modification. This is combined with another method, based on potential of mean force, to calculate interactions between particles. Results show that both contributions are of equal importance for nanoparticle surface acetylation effects. The proposed method is not restricted to either cellulose or acetylation, and has the prospect to find application in a broad context of nanomaterials design.

  • 2.
    Gioia, Claudio
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH Royal Inst Technol, Fibre & Polymer Technol, Stockholm, Sweden..
    Lo Re, Giada
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Biokompositer. KTH Royal Inst Technol, Fibre & Polymer Technol, Stockholm, Sweden..
    Lawoko, Martin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH Royal Inst Technol, Stockholm, Sweden..
    Berglund, Lars
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Biokompositer. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH Royal Inst Technol, Fibre & Polymer Technol, Stockholm, Sweden..
    Tunable polymer systems containing well-characterized derivatives from lignin2019Ingår i: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 257Artikel i tidskrift (Övrigt vetenskapligt)
  • 3.
    Gioia, Claudio
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Lo Re, Giada
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Lawoko, Martin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Berglund, Lars
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Tunable thermosetting epoxies based on fractionated and well-characterized lignins2018Ingår i: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126Artikel i tidskrift (Refereegranskat)
    Ladda ner fulltext (pdf)
    fulltext
  • 4.
    Kaldéus, Tahani
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Träger, Andrea
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Fiberteknologi.
    Berglund, Lars
    KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg.
    Malmström, Eva
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Lo Re, Giada
    Chalmers University of Technology.
    Molecular engineering of cellulose-PCL bio-nanocomposite interface by reactive amphiphilic copolymer nanoparticles2019Ingår i: Artikel i tidskrift (Refereegranskat)
  • 5.
    Kaldéus, Tahani
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Träger, Andrea
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH).
    Berglund, Lars
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH).
    Malmström, Eva
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Lo Re, Giada
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Biokompositer.
    Molecular Engineering of the Cellulose-Poly(Caprolactone) Bio-Nanocomposite Interface by Reactive Amphiphilic Copolymer Nanoparticles2019Ingår i: ACS NANO, ISSN 1936-0851, Vol. 13, nr 6, s. 6409-6420Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A molecularly engineered water-borne reactive compatibilizer is designed for tuning of the interface in melt-processed thermoplastic poly(caprolactone) (PCL)-cellulose nanocomposites. The mechanical properties of the nanocomposites are studied by tensile testing and dynamic mechanical analysis. The reactive compatibilizer is a statistical copolymer of 2-(dimethylamino)ethyl methacrylate and 2-hydroxy methacrylate, which is subsequently esterified and quaternized. Quaternized ammonium groups in the reactive compatibilizer electrostatically match the negative surface charge of cellulose nanofibrils (CNFs). This results in core-shell CNFs with a thin uniform coating of the compatibilizer. This promotes the dispersion of CNFs in the PCL matrix, as concluded from high-resolution scanning electron microscopy and atomic force microscopy. Moreover, the compatibilizer "shell" has methacrylate functionalities, which allow for radical reactions during processing and links covalently with PCL. Compared to the bio-nanocomposite reference, the reactive compatibilizer (<4 wt %) increased Young's modulus by about 80% and work to fracture 10 times. Doubling the amount of peroxide caused further improved mechanical properties, in support of effects from higher cross-link density at the interface. Further studies of interfacial design in specific nanocellulose-based composite materials are warranted since the detrimental effects from CNFs agglomeration may have been underestimated.

  • 6.
    Larsson, Per A.
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för teknikvetenskap (SCI), Centra, VinnExcellens Centrum BiMaC Innovation.
    Linvill, Eric
    KTH, Skolan för teknikvetenskap (SCI), Hållfasthetslära (Inst.). KTH, Skolan för teknikvetenskap (SCI), Centra, VinnExcellens Centrum BiMaC Innovation.
    Lo Re, Giada
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för teknikvetenskap (SCI), Centra, VinnExcellens Centrum BiMaC Innovation.
    Östlund, Sören
    KTH, Skolan för teknikvetenskap (SCI), Hållfasthetslära (Inst.). KTH, Skolan för teknikvetenskap (SCI), Centra, VinnExcellens Centrum BiMaC Innovation.
    Wågberg, Lars
    KTH, Skolan för teknikvetenskap (SCI), Centra, VinnExcellens Centrum BiMaC Innovation. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Ductile and thermoplastic cellulose with novel application and design opportunities2018Ingår i: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 255Artikel i tidskrift (Övrigt vetenskapligt)
  • 7.
    Lo Re, Giada
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Biokompositer.
    Engström, Joakim
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Wu, Qiong
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Biokompositer.
    Malmström, Eva
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Gedde, Ulf W.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Polymera material.
    Olsson, Richard
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Polymera material.
    Berglund, Lars
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Biokompositer. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Improved Cellulose Nanofibril Dispersion in Melt-Processed Polycaprolactone Nanocomposites by a Latex-Mediated Interphase and Wet Feeding as LDPE Alternative2018Ingår i: ACS Applied Nano Materials, ISSN 2574-0970, Vol. 1, nr 6, s. 2669-2677Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This work reports the development of a sustainable and green one-step wet-feeding method to prepare tougher and stronger nanocomposites from biodegradable cellulose nanofibrils (CNF)/polycaprolactone (PCL) constituents, compatibilized with reversible addition fragmentation chain transfer-mediated surfactant-free poly(methyl methacrylate) (PMMA) latex nanoparticles. When a PMMA latex is used, a favorable electrostatic interaction between CNF and the latex is obtained, which facilitates mixing of the constituents and hinders CNF agglomeration. The improved dispersion is manifested in significant improvement of mechanical properties compared with the reference material. The tensile tests show much higher modulus (620 MPa) and strength (23 MPa) at 10 wt % CNF content (compared to the neat PCL reference modulus of 240 and 16 MPa strength), while maintaining high level of work to fracture the matrix (7 times higher than the reference nanocomposite without the latex compatibilizer). Rheological analysis showed a strongly increased viscosity as the PMMA latex was added, that is, from a well-dispersed and strongly interacting CNF network in the PCL.

  • 8.
    Lo Re, Giada
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Biokompositer.
    Sessini, V.
    Wet feeding approach for cellulosic materials/PCL Biocomposites2018Ingår i: Biomass Extrusion and Reaction Technologies: Principles to Practices and Future Potential, American Chemical Society (ACS), 2018, s. 209-226Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    In the past decades, cellulosic materials attracted increasing interest for their potential as reinforcement in bioplastics due to their intrinsic strength and light weight, although uniform fiber dispersion is a challenge. Among biodegradable polyesters, polycaprolactone (PCL) has regained attention for its biodegradability in marine environment together with its ductility. Its low strength, petroleum-based origin and comparably high cost, limit the use of PCL. PCL, therefore, is a good candidate for beneficial effect of cellulose material addition for the preparation of biodegradable composites with improved properties. A one-step wet compounding is reported in this chapter to validate a sustainable method to improve the cellulose dispersion in a hydrophobic polymer matrix as PCL. A comparison between cellulosic wood pulp fibers, microfibrillated cellulose and nanofibrils is made to assess the feasibility of the wet feeding approach for the processing of the biocomposites. Assessment of matrix molar mass demonstrated that PCL is insensitive to the presence of the water during the melt compounding. FE-SEM and X-ray tomography was used to characterize the morphology and to evaluate the nanofibrillation. Tensile tests were carried out to evaluate the mechanical properties of the biocomposites. The shortening and dispersion of the cellulose fibers after the melt processing were evaluated. Young's modulus values indicated that the wet feeding approach improve the dispersion of the cellulose and resulted in enhanced mechanical properties of the biocomposites. The beneficial effect of the wet feeding approach was greater for the pulp fibers compared to the microfibrillated cellulose or the nanofibrils due to a more efficient melt processing and more significant effect on the preservation of the fiber length and their aspect ratio.

  • 9.
    Lo Re, Giada
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Biokompositer. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Spinella, Stephen
    NYU Tandon School of Engineering, Six Metrotech Center, Brooklyn, New York 11201, United States.
    Boujemaoui, Assya
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Biokompositer. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Vilaseca, Fabiola
    BIMATEC Group, Department of Chemical Engineering, Agricultural and Food Technology, University of Girona, C/Maria Aurèlia Capmany 61, 17003 Girona, Spain.
    Larsson, Per Tomas
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Biokompositer. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. RISE Bioeconomy, Teknikringen 56, Stockholm, SE-100 44, Sweden.
    Adås, Fredrik
    RISE Bioeconomy, Teknikringen 56, Stockholm, SE-100 44, Sweden.
    Berglund, Lars
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Biokompositer.
    Poly(ε-caprolactone) Biocomposites Based on Acetylated Cellulose Fibers and Wet Compounding for Improved Mechanical Performance2018Ingår i: ACS Sustainable Chemistry and Engineering, E-ISSN 2168-0485, Vol. 5, nr 6, s. 6753-6760Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Poly(epsilon-caprolactone) (PCL) is a ductile thermoplastic, which is biodegradable in the marine environment. Limitations include low strength, petroleum-based origin, and comparably high cost. Cellulose fiber reinforcement is therefore of interest although uniform fiber dispersion is a challenge. In this study, a one-step wet compounding is proposed to validate a sustainable and feasible method to improve the dispersion of the cellulose fibers in hydrophobic polymer matrix as PCL, which showed to be insensitive to the presence of the water during the processing. A comparison between unmodified and acetylated cellulosic wood fibers is made to further assess the net effect of the wet feeding and chemical modification on the biocomposites properties, and the influence of acetylation on fiber structure is reported (ATR-FTIR, XRD). Effects of processing on nano fibrillation, shortening, and dispersion of the cellulose fibers are assessed as well as on PCL molar mass. Mechanical testing, dynamic mechanical thermal analysis, FE-SEM, and X-ray tomography is used to characterize composites. With the addition of 20 wt % cellulosic fibers, the Young's modulus increased from 240 MPa (neat PCL) to 1850 MPa for the biocomposites produced by using the wet feeding strategy, compared to 690 MPa showed for the biocomposites produced using dry feeling. A wet feeding of acetylated cellulosic fibers allowed even a greater increase, with an additional 46% and 248% increase of the ultimate strength and Young's modulus, when compared to wet feeding of the unmodified pulp, respectively.

    Ladda ner fulltext (pdf)
    fulltext
  • 10.
    Lo Re, Giada
    et al.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Spinella, Stephen
    NYU Polytech Sch Engn, Dept Chem & Biomol Engn, Brooklyn, NY USA.;UMONS Univ Mons, Ctr Innovat & Rech MAt Polymeres CIRMAP, Serv Mat Polymeres & Composites, Mons, Belgium..
    Vilaseca, Fabiola
    Univ Girona, Dept Chem Engn, Agr & Food Technol, Girona, Spain..
    Berglund, Lars
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Melt-processing of cellulose pulp and polycaprolactone composites: Wet feeding approach to improve the filler dispersion2017Ingår i: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 253Artikel i tidskrift (Övrigt vetenskapligt)
  • 11.
    Mianehrow, Hanieh
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Biokompositer. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Lo Re, Giada
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Biokompositer. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Berglund, Lars
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Biokompositer. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Strong nanopaperes based on cellulose nanofibrils and graphene oxide2020Ingår i: ECCM 2018 - 18th European Conference on Composite Materials, Applied Mechanics Laboratory , 2020Konferensbidrag (Refereegranskat)
    Abstract [en]

    With respect to the importance of high performance bio-based composites, an attempt was made to prepare biocomposites based on cellulose nanofibers (CNF) and Graphene oxide (GO) to study the synergistic effect of their superior properties on the mechanical properties of the resultant biocomposite. Mechanical testing showed the addition of only 0.1 wt% of GO to CNF results in a composite with 17.3 GPa modulus. This effective reinforcement by adding a small amount of GO, shows the efficient stress transfer from CNF to GO that is the result of utilizing large GO sheets with high aspect ratio, effective dispersion of GO in the nanocomposite and the layered structure of the resultant nanocomposite.

  • 12.
    Mianehrow, Hanieh
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Biokompositer. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Lo Re, Giada
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Biokompositer. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. Chalmers Univ Technol, Dept Ind & Mat Sci, Rannvagen 2, S-41296 Gothenburg, Sweden..
    Carosio, Federico
    Politecn Torino, Dipartimento Sci Applicata & Tecnol, Alessandria Campus,Via Teresa Michel 5, I-15121 Alessandria, Italy..
    Fina, Alberto
    Politecn Torino, Dipartimento Sci Applicata & Tecnol, Alessandria Campus,Via Teresa Michel 5, I-15121 Alessandria, Italy..
    Larsson, Per Tomas
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Fiberteknologi. RISE Bioecon, Drottning Kristinas Vag 61, SE-11486 Stockholm, Sweden..
    Chen, Pan
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Fiberteknologi. Beijing Inst Technol, Sch Mat Sci & Engn, Beijing Engn Res Ctr Cellulose & Its Derivat, 5 South Zhongguancun St, Beijing 100081, Peoples R China..
    Berglund, Lars
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Biokompositer. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Strong reinforcement effects in 2D cellulose nanofibril-graphene oxide (CNF-GO) nanocomposites due to GO-induced CNF ordering2020Ingår i: Journal of Materials Chemistry A, ISSN 2050-7488, E-ISSN 2050-7496, Vol. 8, nr 34, s. 17608-17620Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Nanocomposites from native cellulose with low 2D nanoplatelet content are of interest as sustainable materials combining functional and structural performance. Cellulose nanofibril-graphene oxide (CNF-GO) nanocomposite films are prepared by a physical mixing-drying method, with a focus on low GO content, the use of very large GO platelets (2-45 mu m) and nanostructural characterization using synchrotron X-ray source for WAXS and SAXS. These nanocomposites can be used as transparent coatings, strong films or membranes, as gas barriers or in laminated form. CNF nanofibrils with random in-plane orientation, form a continuous non-porous matrix with GO platelets oriented in-plane. GO reinforcement mechanisms in CNF are investigated, and relationships between nanostructure and suspension rheology, mechanical properties, optical transmittance and oxygen barrier properties are investigated as a function of GO content. A much higher modulus reinforcement efficiency is observed than in previous polymer-GO studies. The absolute values for modulus and ultimate strength are as high as 17 GPa and 250 MPa at a GO content as small as 0.07 vol%. The remarkable reinforcement efficiency is due to improved organization of the CNF matrix; and this GO-induced mechanism is of general interest for nanostructural tailoring of CNF-2D nanoplatelet composites.

  • 13. Scaffaro, R.
    et al.
    Maio, A.
    Lo Re, Giada
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Biokompositer.
    Parisi, A.
    Busacca, A.
    Advanced piezoresistive sensor achieved by amphiphilic nanointerfaces of graphene oxide and biodegradable polymer blends2018Ingår i: Composites Science And Technology, ISSN 0266-3538, E-ISSN 1879-1050, Vol. 156, s. 166-176Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This work focuses on the preparation of a piezoresistive sensor device, by exploiting an amphiphilic sample of graphene oxide (GO) as a compatibilizer for poly (lactic acid) (PLA)-Poly (ethylene-glycol) (PEG) blends. The presence of GO determined a high stiffening and strengthening effect, without affecting toughness, and allowed a good stability of mechanical properties up to 40 days. Moreover, GO endowed the materials with electrical properties highly sensitive to pressure and strain variations: the biodegradable pressure sensor showed a responsivity of 35 μA/MPa from 0.6 to 8.5 MPa, a responsivity around 19 μA/MPa from 8.5 to 25 MPa. For lower pressure values (around 0.16–0.45 MPa), instead, the responsivity increases up to 220 μA/MPa in terms of ΔI/ΔP (i.e. (ΔI/ΔI0)/P close to 1 kPa−1). Furthermore, this novel sensor is able to monitor submicrometric displacements with an impressive sensitivity (up to 25 μA/μm in terms of ΔI/ΔL, or 70 in terms of (ΔI/I0)/ε). We implemented a model able to predict pressure changes up to 25 MPa, by monitoring and measuring variations in electrical conductivity, thus paving the road to use these biodegradable, ecofriendly materials as low-cost sensors for a large pressure range.

  • 14.
    Sessini, Valentina
    et al.
    Univ Alcala De Henares, Fac Pharm, Dept Organ & Inorgan Chem, Madrid 28805, Spain..
    Haseeb, Bashar
    Chalmers Univ Technol, Dept Ind & Mat Sci, Rannvagen 2A, SE-41296 Gothenburg, Sweden..
    Boldizar, Antal
    Chalmers Univ Technol, Dept Ind & Mat Sci, Rannvagen 2A, SE-41296 Gothenburg, Sweden..
    Lo Re, Giada
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Biokompositer. Chalmers Univ Technol, Dept Ind & Mat Sci, Rannvagen 2A, SE-41296 Gothenburg, Sweden..
    Sustainable pathway towards large scale melt processing of the new generation of renewable cellulose-polyamide composites2021Ingår i: RSC Advances, E-ISSN 2046-2069, Vol. 11, nr 2, s. 637-656Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Modern society's growing demands for accountable high-performance and more environmentally friendly materials is leading to increased interest and fast development of sustainable polymeric composite materials. New generations of "greener" products originating from renewable resources fulfil emerging requirements of low environmental and health & safety impacts and contribute to diminishing global dependence on fossil feedstock. The preparation of sustainable polymeric composites via reliable and reproducible melt-compounding methods is still challenging but has the potential to yield applicable and market competitive products. This literature survey reviews the current state of research involving the use of cellulosic materials, as bio-sourced and sustainable reinforcement in melt-processed polyamides and focuses on the main hurdles that prevent their successful large-scale melt-compounding. Particular emphasis is dedicated to emerging bio-sourced polyamides fitting the performance of engineering materials and at the same time offering additional interesting properties for advanced applications such as piezoelectricity for transducers, sensors, actuators and energy harvesters.

  • 15.
    Soeta, Hiroto
    et al.
    Univ Tokyo, Dept Biomat Sci, Grad Sch Agr & Life Sci, Tokyo 1138657, Japan..
    Lo Re, Giada
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Masuda, Akihiro
    Toray Res Ctr Ltd, Morphol Res Labs, Morphol Res Lab 3, Otsu, Shiga 5208567, Japan..
    Fujisawa, Shuji
    Univ Tokyo, Dept Biomat Sci, Grad Sch Agr & Life Sci, Tokyo 1138657, Japan..
    Saito, Tsuguyuki
    Univ Tokyo, Dept Biomat Sci, Grad Sch Agr & Life Sci, Tokyo 1138657, Japan..
    Berglund, Lars
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Isogai, Akira
    Univ Tokyo, Dept Biomat Sci, Grad Sch Agr & Life Sci, Tokyo 1138657, Japan..
    Tailoring Nanocellulose-Cellulose Triacetate Interfaces by Varying the Surface Grafting Density of Poly(ethylene glycol)2018Ingår i: ACS Omega, E-ISSN 2470-1343, Vol. 3, nr 9, s. 11883-11889Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Careful design of the structures of interfaces between nanofillers and polymer matrices can significantly improve the mechanical and'thermal' properties of the overall nanocomposites. Here, we investigate]how the grafting density on the surface of nanocelluloses influences the properties of nanocellulose/cellulose triacetate (CTA) composites. 2,2,6,6 The surface of nanocellulose, which was preparedby tetramethylpiperidine-l-oxyl oxidation, was modified with long poly(ethylene glycol) (PEG) chains at different grafting_ densities. The PEG -grafted nanocelluloses were h omogene ously embedded in CTA matrices. The mechanical and thermal properties of the nanocomposites were characterized. Increasing the grafting density caused the soft PEG chains to form denser and thicker layers around the rigid nanocelluloses. The PEG layers were not completely miscible with the CTA matrix. This structure consfderably enhanced the energy dissipation by allowing sliding at the interface, which increased the toughness of the nanocomposites. The thermal and mechanical properties of the composites could be tailored by controlling the grafting density. These findings provide a deeper understanding about interfacial design for nanocellulose-based composite materials.

  • 16. Zaldua, N.
    et al.
    Mugica, A.
    Zubitur, M.
    Iturrospe, A.
    Arbe, A.
    Re, Giada Lo
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Raquez, J. -M
    Dubois, P.
    Müller, A. J.
    The role of PLLA-g-montmorillonite nanohybrids in the acceleration of the crystallization rate of a commercial PLA2016Ingår i: CrystEngComm, ISSN 1466-8033, E-ISSN 1466-8033, Vol. 18, nr 48, s. 9334-9344Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Employing the hydroxyl groups on the surface of Cloisite® 30B montmorillonite (Cl30B), the ring-opening polymerization of l-lactide was performed with a metal-free catalyst to yield a PLLA-g-Cl30B nanohybrid with low Mn grafted PLLA chains (i.e., 9 kg mol-1). This nanohybrid was then melt mixed with PLA 4032D from NatureWorks, which is a slow-crystallizing PLA as it contains 2% d-isomers and has a high Mn value (i.e., 123 kg mol-1). The samples were characterized by TEM, WAXS, SAXS, DSC and Polarized Light Optical Microscopy (PLOM) in order to study their crystallization kinetics in depth. The dispersion of the nanoclay was excellent and much better in the PLA/PLLA-g-Cl30B nanocomposites in comparison to PLA/Cl30B blends prepared as reference. In order to ascertain the role of the nanoclay, analogue PLA/PLLA blends without Cl30B were also prepared. The spherulitic crystallization kinetics from the melt was determined for all samples. The growth rate of neat PLA was accelerated approximately 3 times by incorporating the PLLA-g-Cl30B nanohybrid with an inorganic content of 5%. The overall crystallization kinetics from the glassy state of PLA was also accelerated in a similar way by the nanohybrid addition. Nevertheless, the PLA/PLLA blends crystallized even faster indicating that the dominant effect that causes the acceleration of the crystallization of PLA is the plasticization of PLA by the low Mn PLLA molecules. The changes in Tg of PLA also support this explanation. In the case of the PLA/PLLA-g-Cl30B nanocomposites, even though the plasticizing effect of the PLLA chains still dominates, their action is counterbalanced by their tethering on one end, as they are grafted to the surface of the exfoliated clay nanoplatelets.

1 - 16 av 16
RefereraExporteraLänk till träfflistan
Permanent länk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf