Browsing by Author "Morán, Juan"

Filter results by typing the first few letters
Now showing 1 - 4 of 4
  • Thumbnail Image
    Item
    Decorative laminates based on phenolic resins modified with sodium lignosulfonate and kraft lignin: Evaluation of mechanical properties
    (2014-03) Taverna, María E.; Nicolau, Verónica V.; Ollearo, Rocío; Morán, Juan; Frontini, Patricia; Meira, Gregorio; Estenoz, Diana
    The substitution of phenol in the production of resol-type phenolic resins by environmentally-friendly compounds such as lignin and its derivatives is of great technological and academic interest, due to the similarity between resols and the aromatic structure of lignins. However, lignins must be chemically-modified in order to increase their reactivity toward formaldehyde. In this work, the addition of commercial lignins (sodium lignosulfonate and Kraft-type) as partial replacement of phenol in the resols used for decorative laminates production is experimentally studied. The work involved: the characterization and reactivation of commercial lignins, the industrial synthesis of traditional and modified resols by replacement of 10 and 20% w/w of phenol, the industrial impregnation of Kraft-type papers with the produced resins and the production of laminates at laboratory and industrial scales. The mechanical performance of the laminates was deeply assesed by determining tensile modulus, bending strengh, biaxial flexural impact strenght and Mode- I Interlaminar Fracture Toughness in both processing directions. Modified laminates exhibited mechanical properties comparable with those of traditional laminates, indicating a negligible depreciation of them. Industrial tests were carried out at Centro S.A, San Francisco, Córdoba.
  • No Thumbnail Available
    Item
    Effect of Kraft Lignin from Hardwood on Viscoelastic, Thermal, Mechanical and Aging Performance of High Pressure Laminates.
    (Waste and Biomass Valorization, 2017-07-10) Taverna, María E.; Tassara, Oriana; Morán, Juan; Nicolau, Verónica V.; Estenoz, Diana; Frontini, Patricia
    In this work, the synthesis and characterization of phenol-formaldehyde resols modified with 10, 20 and 30 wt% of Kraft lignin (a waste from pulp industry) from hardwood were studied. In all cases, the Kraft lignin was activated by hydroxymethylation. The resols characterization involved industrial measurements of free formaldehyde, viscosity, total solids and density. The resins were used for the industrial impregnation of Kraft-type paper and the production of laboratory laminates. The mechanical and thermal properties of the laminates were determined. Mechanical measurements included tensile, flexural, impact and interlaminar tests. Thermogravimetric and dynamic mechanical analysis were used for the thermal characterization. In addition, the aging of materials in water was studied. No significant differences in mechanical and thermal properties between traditional and modified materials were found with replacement up to 20 wt% of phenol. Modified laminates exhibited better water resistance due to the lignin hydrophobicity. This work was carried out in collaboration with Centro S.A., San Francisco, Córdoba, Argentina, a high pressure-laminates industry.
  • Thumbnail Image
    Item
    Mechanical evaluation of laminates based on phenolic resins using lignins as partial substitutes for phenol
    (Bioresources, 2015-10-28) Taverna, María E.; Ollearo, Rocío; Morán, Juan; Nicolau, Verónica V.; Estenoz, Diana; Frontini, Patricia
    Reducing the consumption of phenol during synthesis of phenolic resins is of great technological and scientific interest because of its economic and environmental implications. In this work, the use of hydroxymethylated lignins as a partial replacement for phenol in resol phenol-formaldehyde resins used for the production of decorative laminates was experimentally studied. The work involved: i) the industrial synthesis of traditional and modified resols with 10%w/w of sodium lignosulfonate and kraft-type lignin; ii) the industrial impregnation of kraft-type paper with the produced resins; iii) the production of laminates on both laboratory and industrial scales; and iv) the measurement of their final properties. The mechanical performance of the laminates was evaluated via the determination of the Young modulus, bending strength, biaxial impact strength, and Mode-I interlaminar fracture toughness. The (modified and traditional) laminates exhibited statistically significant differences in mechanical properties. However, the partial lignin replacement did not produce effects that were detrimental effects to the overall performance of the decorative laminates.
  • Thumbnail Image
    Item
    Synthesis and mechanical properties of laminates based on phenolic resins modified with sodium lignosulfonate.
    (Latin American Applied Research, 2017-05-08) Taverna, María E.; Ollearo, Rocío; Morán, Juan; Nicolau, Verónica V.; Estenoz, Diana; Frontini, Patricia
    The reduction of phenol and/or formalde-hyde consumption during phenolic resin synthesis is of great technological and scientific interest because of its economic and environmental implications. In this work, the addition of sodium lignosulfonate as par-tial replacement of phenol in the phenolic resol base resins used for decorative laminates production is experimentally studied. The work involves: i) the characterization and reactivation of lignosulfonate, ii) the industrial synthesis of traditional and modified resoles by replacement of 10%w/w of phenol, iii) the industrial impregnation of Kraft-type papers with the produced resins, iv) the pro-duction of laminates at laboratory and industrial scale, and, v) the measurement of their final properties. Tensile, bending and impact strength were evaluated. Modified laminates exhibited mechanical properties statistically comparable with those of traditional laminates. Industrial tests were carried out at Centro S.A, San Francisco, Córdoba.