Endre søk
Begrens søket
1 - 5 of 5
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Treff pr side
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
  • Disputationsdatum (tidligste først)
  • Disputationsdatum (siste først)
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
  • Disputationsdatum (tidligste først)
  • Disputationsdatum (siste først)
Merk
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 1.
    Butylina, Svetlana
    et al.
    Department of Mechanical Engineering, Lappeenranta University of Technology.
    Hyvärinen, Marko
    Department of Mechanical Engineering, Lappeenranta University of Technology.
    Kärki, Timo
    Department of Mechanical Engineering, Lappeenranta University of Technology.
    A study of surface changes of wood-polypropylene composites as the result of exterior weathering2012Inngår i: Polymer degradation and stability, ISSN 0141-3910, E-ISSN 1873-2321, Vol. 97, nr 3, s. 337-345Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Outdoor applications of composites raised questions about their durability. In this study, the effects of outdoor weathering on the properties of wood-polypropylene composites with and without pigments were examined. The composites were placed outdoors for one year, and their colour changes were evaluated after 1, 3, 6, 9 and 12 months of weathering. The weathering resulted in considerable colour fading of the composites. Composites containing darker colour pigments had better colour stability. Scanning electron microscopy analysis revealed that surface cracks caused by weathering in a wood-polypropylene composite having a higher polypropylene content were less abundant, and the deterioration of the surface layer was lower compared to composites containing less polymer. Measurements of melting temperatures by differential scanning calorimetry gave a consistent picture of polypropylene degradation in the surface layer. After weathering, a decrease in Charpy impact strength was found for composites characterised by higher moisture absorption.

  • 2.
    Butylina, Svetlana
    et al.
    Department of Mechanical Engineering, Lappeenranta University of Technology.
    Martikka, Ossi
    Department of Mechanical Engineering, Lappeenranta University of Technology.
    Kärki, Timo
    Department of Mechanical Engineering, Lappeenranta University of Technology.
    Weathering properties of coextruded polypropylene-based composites containing inorganic pigments2015Inngår i: Polymer degradation and stability, ISSN 0141-3910, E-ISSN 1873-2321, Vol. 120, s. 10-16Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This study concerns the weathering properties of coextruded polypropylene-based composites containing pigments. Three different pigments were incorporated in the shell layer of the composites: iron oxide, titanium dioxide and zinc oxide. The surface colour, surface gloss and tensile properties were tested. In addition, the weathered surfaces were studied by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The surfaces of the composites containing inorganic pigments were found to have fewer cracks after 500 h of weathering than the surface of the reference composite. The results revealed that the composites containing titanium oxide pigment exhibited better colour stability than the composites made with the other pigments. In spite of its high colour stability in weathering, the tensile properties (strength, Young's modulus and elongation at break) of the composite containing titanium oxide were reduced by weathering. The FTIR analysis revealed that the composite containing zinc oxide had a stabilising effect on polypropylene photo-degradation, which correlates well with the results of mechanical testing, showing that this composite retained its mechanical properties after weathering

  • 3. Mathew, Aji P.
    et al.
    Packirisamy, S.
    PSC Division, VSSC.
    Thomas, Sabu
    Mahatma Gandhi University.
    Studies on the thermal stability of natural rubber/polystyrene interpenetrating polymer networks: thermogravimetric analysis2001Inngår i: Polymer degradation and stability, ISSN 0141-3910, E-ISSN 1873-2321, Vol. 72, nr 3, s. 423-439Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The thermal degradation of natural rubber/polystyrene (NR/PS) interpenetrating polymer networks (IPNs) was studied and the effects of blend ratio, crosslink level and initiating system were analysed. The thermogravimetric analysis (TGA) shows that the IPNs are more stable than the pure components. The full-IPNs have better stability than semi-IPNs which is due to higher entanglement density of full-IPNs. The initial decomposition temperature and temperature for 50% decomposition (T50) increase with increase in concentration and crosslinker level of the plastic phase. The kinetics of degradation were analysed using nine mechanistic equations. The kinetic parameters such as activation energy, Arrhenius parameter and entropy of activation were determined. Thermal ageing studies of the samples were also conducted. The IPNs aged for 72 h at 100°C showed enhanced mechanical strength due to crosslinking on post curing.

  • 4.
    Monti, M.
    et al.
    Proplast Consortium, Strada Comunale Savonesa 9, Rivalta Scrivia (AL).
    Tsampas, S.A.
    Swerea SICOMP AB, Mölndal.
    Fernberg, Patrik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Blomqvist, P.
    SP Technical Research Institute of Sweden, Borås.
    Cuttica, F.
    Dipartimento di Scienza Applicata e Tecnologia, Politecnico di Torino, sede di Alessandria.
    Fina, A.
    Dipartimento di Scienza Applicata e Tecnologia, Politecnico di Torino, sede di Alessandria.
    Camino, G.
    Proplast Consortium, Strada Comunale Savonesa 9, Rivalta Scrivia (AL).
    Fire reaction of nanoclay-doped PA6 composites reinforced with continuous glass fibers and produced by commingling technique2015Inngår i: Polymer degradation and stability, ISSN 0141-3910, E-ISSN 1873-2321, Vol. 121, s. 1-10Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this paper, we report the development of a glass fiber commingled composite (GFCC) based on a nanoclay-doped polyamide 6 (PA6) and the evaluation of its fire reaction. The preparation of the composite comprised several steps. Firstly, the nanoclay was dispersed in the PA6 matrix. Then, the produced compound was spun in filaments and commingled with continuous glass fibers. Finally, the laminate preform was consolidated. Reference samples based on the neat PA6 were produced as well. As a results, although it is well known that, in the presence of a relevant amount of continuous fibers, the behavior of the material is mainly driven by the fibers themselves (e.g. mechanical, thermal, conductive, and so on), the effect of the clay was interesting, especially in flammability test (UL94 vertical burning test), where the total burning time passes from 227 s to 146 s.

  • 5.
    Witkowski, Artur
    et al.
    Centre for Fire and Hazards Science, University of Central Lancashire.
    Girdin, Bertrand
    R2Fire / UMET – UMR CNRS 8207, ENSCL, Avenue Dimitri Mendeleïev – Bât. C7a, CS 90108, 59652 Villeneuve d’Ascq.
    Försth, Michael
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Hewitt, Fiona
    Centre for Fire and Hazards Science, University of Central Lancashire.
    Fontaine, Geêlle
    R2Fire / UMET – UMR CNRS 8207, ENSCL, Avenue Dimitri Mendeleïev – Bât. C7a, CS 90108, 59652 Villeneuve d’Ascq.
    Duquesne, Sophie
    R2Fire / UMET – UMR CNRS 8207, ENSCL, Avenue Dimitri Mendeleïev – Bât. C7a, CS 90108, 59652 Villeneuve d’Ascq.
    Bourbignot, Serge
    R2Fire / UMET – UMR CNRS 8207, ENSCL, Avenue Dimitri Mendeleïev – Bât. C7a, CS 90108, 59652 Villeneuve d’Ascq.
    Hull, T. Richard
    Centre for Fire and Hazards Science, University of Central Lancashire.
    Development of an Anaerobic Pyrolysis Model for Fire Retardant Cable Sheathing Materials2015Inngår i: Polymer degradation and stability, ISSN 0141-3910, E-ISSN 1873-2321, Vol. 113, s. 208-217Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Wire and cable coverings are potentially a major cause of fire in buildings and other installations. As they need to breach fire walls and are frequently located in vertical ducting, they have significant potential to increase the fire hazard. It is therefore important to understand the ignition and burning characteristics of cables by developing a model capable of predicting their burning behaviour for a range of scenarios. The fire performance of electrical cables is usually dominated by the fire performance of the sheathing materials. The complexity of the problem increases when cable sheathing incorporates fire retardants. One-dimensional pyrolysis models have been constructed for cable sheathing materials, based on milligram-scale and bench-scale test data by comparing the performance of three different software tools (ThermaKin, Comsol Multiphysics and FDS, version 6.0.1). Thermogravimetric analysis and differential scanning calorimetry were conducted on powdered cable coatings to determine the thermal degradation mechanism, the enthalpy of decomposition reactions, and the heat capacities of all apparent species. The emissivity and the in-depth absorption coefficient were determined using reflectance and transmittance measurements, with dispersive and non-dispersive spectrometers and integrating spheres. Bench-scale tests were conducted with a mass loss calorimeter flushed with nitrogen on samples in a horizontal orientation, for comparison with the pyrolysis model of non-flaming decomposition at an external heat flux of 50 kW m-2. The parameters determined through analysis of the milligram-scale data were used to construct a pyrolysis model that predicted the total mass loss from calorimeter tests in anaerobic conditions. A condensed phase pyrolysis model that accurately predicts in-depth temperature profiles of a solid fuel, and the mass flux of volatiles evolved during degradation of the fuel, is an essential component of a comprehensive fire model, which when coupled to a computational fluid dynamics code can be used to predict the burning processes in a fire scenario. Pyrolysis models vary considerably in complexity based on the assumptions incorporated into the development of the model.

1 - 5 of 5
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf