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  • 1.
    Badía, J. D.
    et al.
    Universidad Politécnica de Valencia, Spain.
    Moriana, Rosana
    Universidad Politécnica de Valencia, Spain.
    Santonja-Blasco, L.
    Universidad Politécnica de Valencia, Spain.
    Ribes-Greus, A.
    Universidad Politécnica de Valencia, Spain.
    A thermogravimetric approach to study the influence of a biodegradation in soil test to a Poly(lactic acid)2008In: Macromolecular Symposia, ISSN 1022-1360, E-ISSN 1521-3900, Vol. 272, no 1, p. 93-99Article in journal (Refereed)
    Abstract [en]

    An amorphous grade Poly (lactic acid) (PLA) was selected for an accelerated burial in soil test during 450 days. Thermogravimetric analyses were carried out to study the effects of degradation in soil on the thermal stability and the thermal decomposition kinetics. A single stage decomposition process is observed for all degradation times. It is shown that the thermal stability of PLA is slightly affected by degradation in soil. Concerning the study of the thermal decomposition kinetics, Criado master curves were plotted from experimental data to focus the study of the thermodegradation kinetic model.The kinetic methods proposed by Broido and Chang were used to calculate the apparent activation energies (Ea) of the degradation mechanism. These results were compared to the Ea values obtained by the method developed by Coats and Redfern in order to prove the applicability of the former methods to the kinetic study. As expected, non-linear tendency is found out for Ea variation along the degradation times, which can be explained as an evolution by stages. Copyright © 2008 WILEY-VCH Verlag GmbH & Co. KGaA.

  • 2.
    Badía, José David
    et al.
    Instituto de Investigación en Tecnología de Materiales, Universidad Politécnica de Valencia, Spain.
    Santonja-Blasco, Laura
    Instituto de Investigación en Tecnología de Materiales, Universidad Politécnica de Valencia, Spain.
    Moriana, Rosana
    Instituto de Investigación en Tecnología de Materiales, Universidad Politécnica de Valencia, Spain.
    Ribes-Greus, Amparo
    Instituto de Investigación en Tecnología de Materiales, Universidad Politécnica de Valencia, Spain.
    Thermal analysis applied to the characterization of degradation in soil of polylactide: II. on the thermal stability and thermal decomposition kinetics2010In: Polymer degradation and stability, ISSN 0141-3910, E-ISSN 1873-2321, Vol. 95, no 11, p. 2192-2199Article in journal (Refereed)
    Abstract [en]

    The disposal stage of polylactide (PLA) was assessed by burying it in active soil following an international standard. Degradation in soil promotes physical and chemical changes in the polylactide properties. The characterization of the extent of degradation underwent by PLA was carried out by using Thermal Analysis techniques. In this paper, studies on the thermal stability and the thermal decomposition kinetics were performed in order to assess the degradation process of a commercial PLA submitted to an accelerated soil burial test by means of multi-linear-non-isothermal thermogravimetric analyses. Results have been correlated to changes in molecular weight, showing the same evolution as that described by the parameters of thermal stability temperatures and apparent activation energies. The decomposition reactions can be described by two competitive different mechanisms: Nucleation model (A2) and Reaction Contracting Volume model (R3). The changes in the kinetic parameters and kinetic models are in agreement with the calorimetric and dynamic-mechanical-thermal results, presented in the Part I of the study [1]. © 2010 Elsevier Ltd. All rights reserved.

  • 3.
    España Giner, Jose Manuel
    et al.
    Polytechnic University of Valencia, Alcoy, Spain.
    Fages, Eduardo
    Textile Research Institute, Alcoy, Spain.
    Boronat Vitoria, Teodomiro
    Polytechnic University of Valencia, Alcoy, Spain.
    Moriana Torró, Rosana
    Textile Research Institute, Alcoy, Spain.
    Balart Gimeno, Rafael Antonio
    Polytechnic University of Valencia, Alcoy, Spain.
    Antioxidant effects of natural compounds on green composite materials2012In: Plastics Research Online, p. 1-3Article in journal (Other academic)
    Abstract [en]

    Naturally-occurring antioxidant compounds can improve the thermal resistance of a bio-composite, increasing the degradation temperature of the material by as much as 130%.

  • 4.
    España, J. M.
    et al.
    Instituto de Tecnología de Materiales (ITM), Universitat Politècnica de València (UPV), Alcoy (Alicante), Spain.
    Fages, E.
    Textile Research Institute (AITEX), Alcoy (Alicante), Spain.
    Moriana, Rosana
    Textile Research Institute (AITEX), Alcoy (Alicante), Spain.
    Boronat, T.
    Instituto de Tecnología de Materiales (ITM), Universitat Politècnica de València (UPV), Alcoy (Alicante), Spain.
    Balart, R.
    Instituto de Tecnología de Materiales (ITM), Universitat Politècnica de València (UPV), Alcoy (Alicante), Spain.
    Antioxidant and antibacterial effects of natural phenolic compounds on green composite materials2012In: Polymer Composites, ISSN 0272-8397, E-ISSN 1548-0569, Vol. 33, no 8, p. 1288-1294Article in journal (Refereed)
    Abstract [en]

    The aim of this study is to establish the thermal performance of a biocomposite (Arbofill kokos®), stabilized with different natural phenolic additives, to check the antioxidant capacity of the resulting compounds. Different phenolic compounds (thymol, carvacrol, α-tocopherol, and tannic acid) were used as biobased additives and the concentrations ranged between 0.5 wt% and 2 wt%. The results obtained were compared with formulations containing a typical industrial petroleum-based antioxidant agent (octadecyl-3-(3,5-di-tert- butyl-4-hydroxyphenyl) propionate). Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to characterize the antioxidant performance of the selected natural additives. The antimicrobial effect of these natural phenolic compounds was also studied by analyzing the growth of bacterial colonies. The comparison between the natural phenolic compounds and the petroleum-based antioxidant compound showed good antioxidant action for natural phenolic compounds; in all the mixtures of biocomposite and antioxidant agent the oxidation onset temperature (OOT) increased in a remarkable way, but the highest stabilization effect was achieved with α-tocopherol with provides a % increase on OOT of about 45%. With regard to antibacterial activity of the different natural phenolic compounds, thymol, and carvacrol showed interesting antibacterial properties against Staphylococcus aureus. Copyright © 2012 Society of Plastics Engineers.

  • 5.
    Ferrero, B.
    et al.
    Universitat Politècnica de València (UPV), Alcoy (Alicante), Spain.
    Boronat, T.
    Universitat Politècnica de València (UPV), Alcoy (Alicante), Spain.
    Moriana, Rosana
    KTH Royal Institute of Technology.
    Fenollar, O.
    Universitat Politècnica de València (UPV), Alcoy (Alicante), Spain.
    Balart, R.
    Universitat Politècnica de València (UPV), Alcoy (Alicante), Spain.
    Green composites based on wheat gluten matrix and posidonia oceanica waste fibers as reinforcements2013In: Polymer Composites, ISSN 0272-8397, E-ISSN 1548-0569, Vol. 34, no 10, p. 1663-1669Article in journal (Refereed)
    Abstract [en]

    In this work, green composites from renewable resources were manufactured and characterized. A fibrous material derived from Posidonia oceanica wastes with high cellulose content (close to 90 wt% of the total organic component) was used as reinforcing material. The polymeric matrix to bind the fibers was a protein (wheat gluten) type material. Composites were made by hot-press molding by varying the gluten content on composites in the 10-40 wt% range. Mechanical properties were evaluated by standardized flexural tests. Thermo-mechanical behavior of composites was evaluated with dynamic mechanical analysis (torsion DMA) and determination of heat deflection temperature. Morphology of samples was studied by scanning electronic microscopy and the water uptake in terms of the water submerged time was evaluated to determine the maximum water uptake of the fibers in the composites. Composites with 10-40 wt% gluten show interesting mechanical performance, similar or even higher to many commodity and technical plastics, such as polypropylene. Water resistance of these composites increases with the amount of gluten. Therefore, the sensitiveness to the water of the composites can be tailored with the amount of gluten in their formulation.

  • 6.
    García-García, Daniel
    et al.
    Instituto de Tecnología de Materiales (ITM), Universitat Politècnica de València (UPV), Alicante, Spain.
    Balart, Rafael
    Instituto de Tecnología de Materiales (ITM), Universitat Politècnica de València (UPV), Alicante, Spain.
    Lopez-Martinez, Juan
    Instituto de Tecnología de Materiales (ITM), Universitat Politècnica de València (UPV), Alicante, Spain.
    Ek, Monica
    School of Engineering Sciences in Chemistry, Biotechnology and Health, Department of Fibre and Polymer Technology, KTH-Royal Institute of Technology, Stockholm, Sweden.
    Moriana, Rosana
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. School of Engineering Sciences in Chemistry, Biotechnology and Health, Department of Fibre and Polymer Technology, KTH-Royal Institute of Technology, Stockholm, Sweden.
    Optimizing the yield and physico-chemical properties of pine cone cellulose nanocrystals by different hydrolysis time2018In: Cellulose (London), ISSN 0969-0239, E-ISSN 1572-882X, Vol. 25, no 5, p. 2925-2938Article in journal (Refereed)
    Abstract [en]

    Cellulose nanocrystals (CNCs) were isolated for the first time from pine cones (PC) by alkali and bleaching treatments and subsequent sulfuric acid hydrolysis (64%) at 45 degrees C. The influence of the hydrolytic reaction time (30, 45, and 90 min) on the yield, chemical composition and structure, and thermal stability of CNCs was evaluated. The removal of non-cellulosic constituents during the alkaline and bleaching treatment resulted in high pure cellulosic fibres. The isolation of CNCs from these cellulosic fibres at different reaction times was verified by the nano-dimensions of the individual crystals (< 3 and < 335 nm of average diameter and length, respectively). The highest yield (15%) and the optimum CNCs properties in terms of aspect ratio, thermal stability and crystallinity were obtained for an extraction time of 45 min. PC appeared to be a new promising source of cellulose fibres and CNCs with potential to be applied as reinforcement in composites and for food-packaging.

  • 7.
    García-García, Daniel
    et al.
    Instituto de Tecnología de Materiales-ITM, Universitat Politècnica de València, Alicante, Spain.
    Lopez-Martínez, Juan
    Instituto de Tecnología de Materiales-ITM, Universitat Politècnica de València, Alicante, Spain.
    Rafael, Balart
    Instituto de Tecnología de Materiales-ITM, Universitat Politècnica de València, Alicante, Spain.
    Strömberg, Emma
    School of Engineering Science in Chemistry, Biotechnology and Health, Department of Fibre and Polymer Technology, KTH-Royal Institute of Technology, Stockholm, Sweden.
    Moriana, Rosana
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. School of Engineering Science in Chemistry, Biotechnology and Health, Department of Fibre and Polymer Technology, KTH-Royal Institute of Technology, Stockholm, Sweden.
    Reinforcing capability of cellulose nanocrystals obtained from pine cones in a biodegradable poly(3-hydroxybutyrate)/poly(ε-caprolactone) (PHB/PCL) thermoplastic blend2018In: European Polymer Journal, ISSN 0014-3057, E-ISSN 1873-1945, Vol. 104, p. 10-18Article in journal (Refereed)
    Abstract [en]

    In this work, different loads (3, 5 and 7 wt%) of pine cone cellulose nanocrystals (CNCs) were added to films ofpoly(3-hydroxybutyrate)/poly(ε-caprolactone) (PHB/PCL) blends with a composition of 75 wt% PHB and 25 wt% PCL (PHB75/PCL25). The films were obtained after solvent casting followed by melt compounding in anextruder and finally subjected to a thermocompression process. The influence of different CNCs loadings on themechanical, thermal, optical, wettability and disintegration in controlled compost properties of the PHB75/PCL25blend was discussed. Field emission scanning electron microscopy (FESEM) revealed the best dispersion of CNCson the polymeric matrix was at a load of 3 wt%. Over this loading, CNCs aggregates were formed enhancing thefilms fragilization due to stress concentration phenomena. However, the addition of CNCs improved the opticalproperties of the PHB75/PCL25films by increasing their transparency and accelerated the film disintegration incontrolled soil conditions. In general, the blend with 3 wt% CNCs offers the best balanced properties in terms ofmechanical, thermal, optical and wettability

  • 8.
    Gordobil, Oihana
    et al.
    University of the Basque Country, Donostia-San Sebastián, Spain.
    Moriana, Rosana
    KTH Royal Institute of technology.
    Zhang, Liming
    KTH Royal Institute of technology.
    Labidi, Jalel
    University of the Basque Country, Donostia-San Sebastián, Spain.
    Sevastyanova, Olena
    KTH Royal Institute of technology.
    Assesment of technical lignins for uses in biofuels and biomaterials: Structure-related properties, proximate analysis and chemical modification2016In: Industrial crops and products (Print), ISSN 0926-6690, E-ISSN 1872-633X, Vol. 83, p. 155-165Article in journal (Refereed)
    Abstract [en]

    The potential of organosolv and kraft eucalyptus and spruce lignin as feedstock for polymeric materials and biofuel applications was assessed. Proximate analysis was used to predict the heating values and char formation. Chemical modification, based on the esterification reaction with methacryloyl chloride, was applied to introduce vinyl groups into the lignin macromolecules for enhanced reactivity. Kraft eucalyptus and spruce lignins had a more condensed structure than organosolv lignins, which resulted in greater thermal stability for these lignins. For different species within the same process, the thermal parameters showed a correlation with certain structural and compositional parameters (ash and sugars content, molecular weight and degree of condensation). Organosolv spruce lignin produced the highest heating value of 24. MJ/Kg, which is suitable for biofuel applications. The content of phenolic OH groups was higher for kraft lignins and especially higher for softwood lignins, both organosolv and kraft. The degree of methacrylation, estimated from the content of vinyl groups per C9 lignin unit, was significantly greater for organosolv lignins than for kraft lignins despite the higher OH-groups content in the latter.

  • 9.
    Le Normand, Myriam
    et al.
    KTH Royal Institute of Technology.
    Moriana, Rosana
    KTH Royal Institute of Technology.
    Ek, Monica
    KTH Royal Institute of Technology.
    Isolation and characterization of cellulose nanocrystals from spruce bark in a biorefinery perspective2014In: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344, Vol. 111, p. 979-987Article in journal (Refereed)
    Abstract [en]

    The present study reports for the first time the isolation of cellulose fibers and cellulose nanocrystals (CNCs) from the bark of Norway spruce. The upgrading of bark cellulose to value-added products, such as CNCs, is part of the "bark biorefinery" concept. The removal of non-cellulosic constituents was monitored throughout the isolation process by detailed chemical composition analyses. The morphological investigation of the CNCs was performed using AFM and showed the presence of nanocrystals with an average length of 175.3 nm and a diameter of 2.8 nm, giving an aspect ratio of around 63. X-ray diffraction (XRD) analyses showed that the crystallinity index increased with successive treatments to reach a final value greater than 80% for CNCs. The thermal degradation of the isolated bark CNCs started at 190 degrees C Spruce bark appeared to be a new promising industrial source of cellulose fibers and CNCs.

  • 10.
    Le Normand, Myriam
    et al.
    KTH Royal Institute of Technology.
    Moriana, Rosana
    KTH Royal Institute of Technology.
    Ek, Monica
    KTH Royal Institute of Technology.
    The bark biorefinery: a side-stream of the forest industry converted into nanocomposites with high oxygen-barrier properties2014In: Cellulose (London), ISSN 0969-0239, E-ISSN 1572-882X, Vol. 21, no 6, p. 4583-4594Article in journal (Refereed)
    Abstract [en]

    The purpose of the bark biorefinery concept is to upgrade the different constituents present in bark to multiple value-added bio-based products. Non-cellulosic polysaccharides (NCP) and cellulose nanocrystals (CNC) sequentially isolated from the inner bark of Norway spruce were used as raw materials for the formulation of renewable nanocomposites. The film formation abilities of NCP/CNC formulations prepared with different proportions of CNC were studied. Homogeneous transparent films with a glossy appearance were obtained when more than 30 wt% CNC was incorporated. The influence of the CNC content on the NCP/CNC films was assessed in terms of structural, thermal, mechanical and oxygen-barrier properties. All the films showed better performances with increasing CNC content, which was explained by the strong interactions between the two components. The effect on the film performances of adding sorbitol as a plasticizer was also evaluated. The presence of sorbitol decreased the thermal stability, the stiffness and the oxygen permeability of the films at 80 % RH. However, the addition of sorbitol enhanced the elongation of the films and further improved their oxygen-barrier properties at 50 % RH. The composite properties could thus be tailored by adding different amounts of sorbitol and CNC, resulting in all-carbohydrate materials with performances similar to or even better than the conventional barrier materials used in packaging.

  • 11.
    Li, Dongfang
    et al.
    KTH Royal Institute of Technology.
    Moriana, Rosana
    KTH Royal Institute of Technology.
    Ek, Monica
    KTH Royal Institute of Technology.
    From forest residues to hydrophobic nanocomposites with high oxygen-barrier properties2016In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 31, no 2, p. 261-269Article in journal (Refereed)
    Abstract [en]

    A biorefinery of forest resources should be able to convert all components of trees, including the bark and other types of forest residues, into value-added products. Here, non-cellulosic polysaccharides (NCPs) isolated from Norway spruce bark and cellulose nanocrystals (CNCs) isolated from the logging residues of Norway spruce were mixed to prepare nanocomposites with competitive thermo-mechanical properties. Polyepoxy acid (PEA) derived from a monomer of suberin in birch bark was used as a coating on the nanocomposites to develop functional materials entirely based on forest resources. All of the PEA-coated nanocomposites were hydrophobic. At 50% and 80% relative humidity, they showed high oxygen-barrier properties that were comparable to or even better than those of some renewable materials such as xylan-, galactoglucomannan- and nanofibrillated cellulose-based films and synthetic materials such as polyvinylidene chloride and polyamide.

  • 12.
    Mendoza, Ana Isabel
    et al.
    KTH-Royal Institute of Technology, Fibre and Polymer Technology, Stockholm, Sweden.
    Moriana, Rosana
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. KTH-Royal Institute of Technology, Fibre and Polymer Technology, Stockholm / SLU-Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Hillborg, Henrik
    ABB-Corporate Research, Power Technology, Västerås, Sweden.
    Strömberg, Emma
    KTH-Royal Institute of Technology, Fibre and Polymer Technology, Stockholm, Sweden.
    Super-hydrophobic zinc oxide/silicone rubber nanocomposite surfaces2019In: Surfaces and Interfaces, ISSN 2468-0230, Vol. 14, p. 146-157Article in journal (Refereed)
    Abstract [en]

    This study presents comparative assessments on hydrophilic and hydrophobic ZnO nanoparticles and their deposition methods on the surface hydrophobicity of silicone rubber (PDMS) and glass substrates. The influence on the surface hydrophobicity and wettability of all the variables regarding the deposition methodologies and the interaction of the nanoparticles with the substrates were within the scope of this study. The different surfaces created by spraying, dipping and drop-pipetting deposition methods were assessed by static contact angle measurements and contact angle hysteresis from advancing and receding angles, as well as by the calculation of the sliding angle and the surface energy parameters. An accurate methodology to determine the contact angle hysteresis was proposed to obtain repetitive and comparative results on all surfaces. All the measurements have been correlated with the morphology and topography of the different surfaces analysed by FE-SE microscopy. The spray-deposition of hydrophobic ZnO nanoparticles on PDMS resulted in super-hydrophobic surfaces, exhibiting hierarchical structures with micro-and nanometer features which, together with the low surface energy, promotes the Cassie-Baxter wetting behavior. This study provides the fundamental approach to select critically the most promising combination in terms of materials and deposition techniques to create silicone-based super-hydrophobic surfaces with potential to be applied in high voltage outdoor insulation applications.

  • 13.
    Moriana, Rosana
    et al.
    Instituto de Tecnología de Materiales (ITM), Universidad Politécnica de Valencia, Spain.
    Karlsson, Sigbritt
    KTH Royal Institute of Technology.
    Ribes-Greus, Amparo
    Instituto de Tecnología de Materiales (ITM), Universidad Politécnica de Valencia, Spain.
    Assessing the influence of cotton fibers on the degradation in soil of a thermoplastic starch-based biopolymer2010In: Polymer Composites, ISSN 0272-8397, E-ISSN 1548-0569, Vol. 31, no 12, p. 2102-2111Article in journal (Refereed)
    Abstract [en]

    Biocomposites consisting of cotton fibers and a commercial starch-based thermoplastic were subjected to accelerated soil burial test. Fourier transform infrared (FTIR) spectrometry analysis was carried out to provide chemical-structural information of the polymeric matrix and its reinforced biocomposites. The effects that take place as a consequence of the degradation in soil of both materials were studied by FTIR-ATR, differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). When the polymeric matrix and the reinforced biocomposite are submitted to soil burial test, the infrared studies display a decrease in the C=O band associated to the ester group of the synthetic component as a consequence of its degradation. The crystalline index of both materials decreased as a function of the degradation process, where the crystalline structure of the reinforced biocomposite was the most affected. In accordance, the degraded reinforced biocomposite micrographs displayed a more damaged morphology and fracture surface than the degraded polymeric matrix micrographs. On the other hand, the same thermal decomposition regions were assessed for both materials, regardless of the degradation time. Kissinger, Criado, and Coats-Redfern methods were applied to analyze the thermogravimetric results. The kinetic triplet of each thermal decomposition process was determined for monitoring the degradation test. The thermal study confirms that starch was the most biodegradable polymeric matrix component in soil. However, the presence of cotton fiber modified the degradation rate of both matrix components; the degradability in soil of the synthetic component was slightly enhanced, whereas the biodegradation rate of the starch slowed down as a function of the soil exposure time. © 2010 Society of Plastics Engineers.

  • 14.
    Moriana, Rosana
    et al.
    University Polytechnic of Valencia (UPV), Spain.
    Karlsson, Sigbritt
    KTH Royal Institute of Technology.
    Ribes-Greus, Amparo
    Reinforced biocomposites with guaranteed degradability in soil2010In: Plastics Research OnlineArticle in journal (Other academic)
    Abstract [en]

    The addition of cotton fibers to a starch-based commercial material maintains its thermal stability and assures its biodegradation.

  • 15.
    Moriana, Rosana
    et al.
    KTH Royal Institute of Technology, School of Chemical Science and Engineering, Fibre and Polymer Technology, Stockholm, Sweden / Materials Technology Institute (ITM), School of Design Engineering (ETSID), Polytechnic University of Valencia, Spain.
    Strömberg, Emma
    KTH Royal Institute of Technology, School of Chemical Science and Engineering, Fibre and Polymer Technology, Stockholm, Sweden.
    Ribes, Amparo
    Materials Technology Institute (ITM), School of Design Engineering (ETSID), Polytechnic University of Valencia, Spain.
    Karlsson, Sigbritt
    KTH Royal Institute of Technology, School of Chemical Science and Engineering, Fibre and Polymer Technology, Stockholm, Sweden.
    Degradation behaviour of natural fibre reinforced starch-based composites under different environmental conditions2014In: Journal of Renewable Materials, ISSN 2164-6325, E-ISSN 2164-6341, Vol. 2, no 2, p. 145-156Article in journal (Refereed)
    Abstract [en]

    The purpose of this work was to study the effect of hydrothermal, biological and photo degradation on natural fibres reinforced biodegradable starch-based (Mater-BiKE) composites to characterize the structural changes occurring under exposure to different environments. The composites water-uptake rate was hindered by the interfacial interactions between matrix and fibres. Thermal, structural and morphological analysis provided useful information about the irreversible changes in the properties of the composites caused by degradation in soil and photodegradation, and their synergetic effects. The effects due to the photo-oxidation and degradation in soil on the composites depended on the different chemical composition of each fibre. The composite with more hemicellulose and lignin in its formulation was more affected by both types of degradation, but still the end result properties were better than the ones shown for the degraded Mater-BiKE. The photo-oxidation of all the studied materials achieved enhanced degradation rate in soil. The Mater-BiKE/ kenaf was shown to have the slowest water-uptake rate and better thermal properties once photo-oxidized, indicating better service life conditions. At the same time, the Mater-BiKE/kenaf was affected to a major extent by the synergetic effects of both photo-oxidation and soil burial test, showing a faster degradative rate and better disposal conditions. © 2014 Scrivener Publishing LLC.

  • 16.
    Moriana, Rosana
    et al.
    KTH Royal Institute of Technology.
    Vilaplana, Francisco
    KTH Royal Institute of Technology.
    Ek, Monica
    KTH Royal Institute of Technology.
    Cellulose Nanocrystals from Forest Residues as Reinforcing Agents for Composites: A Study from Macro- to Nano-Dimensions2016In: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344, Vol. 139, p. 139-149Article in journal (Refereed)
    Abstract [en]

    This study investigates for the first time the feasibility of extracting cellulose nanocrystals (CNCs) from softwood forestry logging residues (woody chips, branches and pine needles), with an obtained gravimetric yield of over 13%. Compared with the other residues, woody chips rendered a higher yield of bleached cellulosic fibers with higher hemicellulose, pectin and lignin content, longer diameter, and lower crystallinity and thermal stability. The isolation of CNCs from these bleached cellulosic fibers was verified by the removal of most of their amorphous components, the increase in the crystallinity index, and the nano-dimensions of the individual crystals. The differences in the physico-chemical properties of the fibers extracted from the three logging residues resulted in CNCs with specific physico-chemical properties. The potential of using the resulting CNCs as reinforcements in nanocomposites was discussed in terms of aspect ratio, crystallinity and thermal stability.

  • 17.
    Moriana, Rosana
    et al.
    KTH Royal Institute of Technology.
    Vilaplana, Francisco
    KTH Royal Institute of Technology.
    Ek, Monica
    KTH Royal Institute of Technology.
    Forest residues as renewable resources for bio-based polymeric materials and bioenergy: chemical composition, structure and thermal properties2015In: Cellulose (London), ISSN 0969-0239, E-ISSN 1572-882X, Vol. 22, no 5, p. 3409-3423Article in journal (Refereed)
    Abstract [en]

    The potential of three different logging residues (woody chips, branches and pine needles) as renewable resources to produce environmentally friendly polymeric materials and/or biofuel has been critically evaluated in terms of their structure, chemical composition and thermal properties. Woody chips constitute the most attractive forest residue to be processed into polymeric materials in terms of their highest cellulose content, crystallinity and thermal stability. In contrast, pine needles and branches offer higher heating values and optimum product distribution for solid fuel applications due to their higher lignin content. In general, forest residual biomass has great potential for conversion into new added value products, such as composites or solid biofuel, thus constituting a sustainable waste management procedure from a biorefinery perspective. The correlation between the chemical and structural properties with the thermal/pyrolytic behavior of residual biomass offers valuable insights to assess their sustainable exploitation.

  • 18.
    Moriana, Rosana
    et al.
    KTH Royal Institute of Technology / Universidad Politécnica de Valencia, Spain.
    Vilaplana, Francisco
    KTH Royal Institute of Technology / Wallenberg Wood Science Centre (WWSC).
    Karlsson, Sigbritt
    University of Skövde. KTH Royal Institute of Technology.
    Ribes, Amparo
    Universidad Politécnica de Valencia, Spain.
    Correlation of chemical, structural and thermal properties of natural fibres for their sustainable exploitation2014In: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344, Vol. 112, p. 422-431Article in journal (Refereed)
    Abstract [en]

    The potential of lignocellulosic natural fibres as renewable resources for thermal conversion and material reinforcement is largely dependent on the correlation between their chemical composition, crystalline structure and thermal decomposition properties. Significant differences were observed in the chemical composition of cotton, flax, hemp, kenaf and jute natural fibres in terms of cellulose, hemicellulose and lignin content, which influence their morphology, thermal properties and pyrolysis product distribution. A suitable methodology to study the kinetics of the thermal decomposition process of lignocellulosic fibres is proposed combining different models (Friedman, Flynn-Wall-Ozawa, Criado and Coats-Redfern). Cellulose pyrolysis can be modelled with similar kinetic parameters for all the natural fibres whereas the kinetic parameters for hemicellulose pyrolysis show intrinsic differences that can be assigned to the heterogeneous hemicellulose sugar composition in each natural fibre. This study provides the ground to critically select the most promising fibres to be used either for biofuel or material applications.

  • 19.
    Moriana, Rosana
    et al.
    Universidad Politécnica de Valencia, Spain.
    Vilaplana, Francisco
    KTH – Royal Institute of Technology.
    Karlsson, Sigbritt
    KTH – Royal Institute of Technology.
    Ribes-Greus, Amparo
    Universidad Politécnica de Valencia, Spain.
    Improved thermo-mechanical properties by the addition of natural fibres in starch-based sustainable biocomposites2011In: Composites. Part A, Applied science and manufacturing, ISSN 1359-835X, E-ISSN 1878-5840, Vol. 42, no 1, p. 30-40Article in journal (Refereed)
    Abstract [en]

    Sustainable biocomposites based on thermoplastic starch copolymers (Mater-Bi KE03B1) and biofibres (cotton, hemp and kenaf) were prepared and characterised in terms of their thermo-mechanical and morphological properties. Biocomposites exhibit improved thermal stability and mechanical properties in comparison with the Mater-Bi KE. Biofibres act as suitable thermal stabilizers for the Mater-Bi KE, by increasing the maximum decomposition temperature and the Ea associated to the thermal decomposition process. Biofibre addition into the Mater-Bi KE results in higher storage modulus and in a reduction of the free-volume-parameter associated to the Mater-Bi KE glass transition. The influence of different biofibres on the thermo-mechanical properties of the biocomposites has been discussed. Hemp and kenaf enhance the thermal stability and reduce the free volume-parameter of Mater-Bi KE more significantly than cotton fibres, although the latter exhibits the highest mechanical performance. These differences may be explained by the improved interaction of lignocellulosic fibres with the Mater-Bi KE, due to the presence of hemicellulose and lignin in their formulation. © 2010 Elsevier Ltd. All rights reserved.

  • 20.
    Moriana, Rosana
    et al.
    KTH Royal Institute of Technology.
    Vilaplana, Francisco
    KTH Royal Institute of Technology.
    Zhang, Yujia
    KTH Royal Institute of Technology.
    Ek, Monica
    KTH Royal Institute of Technology.
    Using waste biomass to obtain a renewable nanocomposite based on cellulosic biofibre and cereal wall polymers2013In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 245, article id 74-CELLArticle in journal (Other academic)
  • 21.
    Moriana, Rosana
    et al.
    KTH Royal Institute of Technology.
    Zhang, Yujia
    KTH Royal Institute of Technology.
    Mischnick, Petra
    Technische Universität Braunschweig, Germany.
    Li, Jiebing
    KTH Royal Institute of Technology.
    Ek, Monica
    KTH Royal Institute of Technology / Chalmers University of Technology.
    Thermal degradation behavior and kinetic analysis of spruce glucomannan and its methylated derivatives2014In: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344, Vol. 106, no 1, p. 60-70Article in journal (Refereed)
    Abstract [en]

    The thermal degradation behavior and kinetics of spruce glucomannan (SGM) and its methylated derivatives were investigated using thermogravimetric analysis to characterize its temperature-dependent changes for use in specific applications. The results were compared with those obtained for commercial konjac glucomannan (KGM). The SGM and the KGM exhibited two overlapping peaks from 200 to 375 C, which correspond to the intensive devolatilization of more than 59% of the total weight. Differences in the pyrolysis-product distributions and thermal stabilities appeared as a result of the different chemical compositions and molecular weights of the two GMs. The Friedman and Flynn-Wall-Ozawa isoconversional methods and the Coats-Redfern were adopted to determine the kinetic triplet of the intensive devolatilization region. Both GMs can be modeled using a complex mechanism that involves both a Dn-type and an Fn-type reaction. The comparative study of partially methylated GM indicated higher homogeneity and thermal resistance for the material with the higher degree of substitution.

  • 22.
    Moriana-Torró, Rosana
    et al.
    Instituto de Tecnología de Materiales, Escuela Técnica Superior de Ingeniería del Diseño, Universidad Politécnica de Valencia, Spain.
    Contat-Rodrigo, L.
    Instituto de Tecnología de Materiales, Escuela Técnica Superior de Ingeniería del Diseño, Universidad Politécnica de Valencia, Spain.
    Santonja-Blasco, L.
    Instituto de Tecnología de Materiales, Escuela Técnica Superior de Ingeniería del Diseño, Universidad Politécnica de Valencia, Spain.
    Ribes-Greus, A.
    Instituto de Tecnología de Materiales, Escuela Técnica Superior de Ingeniería del Diseño, Universidad Politécnica de Valencia, Spain.
    Thermal characterisation of photo-oxidized HDPE/Mater-Bi and LDPE/Mater-Bi blends buried in soil2008In: Journal of Applied Polymer Science, ISSN 0021-8995, E-ISSN 1097-4628, Vol. 109, no 2, p. 1177-1188Article in journal (Refereed)
    Abstract [en]

    Blends of high and low density polyethylene with a commercial biodegradable material (Mater-Bi) were subjected to an accelerated soil burial test. A set of samples was previously photo-oxidized to evaluate the effects of UV-irradiation on the degradation in soil process of these blends. Thermogravimetric as well as calorimetric analysis were performed to study the biodegradation, photo-degradation and their synergetic effects. Differential scanning calorimetry was carried out to analyze the morphological changes as a consequence of the photo-oxidation process. UV-irradiation slightly modifies the crystalline content of HDPE/Mater-Bi blends, increasing the heterogeneity of this blend. Criado master curves were plotted to analyses the degradation kinetic model. Broido and Coats-Redfern methods have been used for calculating the Ea of the thermal decomposition mechanisms. Thermogravimetric results reveal that noncomplexed starch is more affected by biodegradation than the polyethylene matrix and the starch/EVPH complexes chains from Mater-Bi. However, the effects of both photo-oxidation and biodegradation processes on the thermal decomposition of Mater-Bi is influenced by the polymeric matrix used. Previous photo-oxidation finds to slow down the degradative effects caused by the soil burial test on the HDPE/Mater-Bi blends. © 2008 Wiley Periodicals, Inc.

  • 23.
    Oinonen, Petri
    et al.
    KTH Royal Institute of Technology.
    Krawczyk, Holger
    Lund University.
    Ek, Monica
    KTH Royal Institute of Technology.
    Henriksson, Gunnar
    KTH Royal Institute of Technology.
    Moriana, Rosana
    KTH Royal Institute of Technology.
    Bioinspired composites from cross-linked galactoglucomannan and microfibrillated cellulose: Thermal, mechanical and oxygen barrier properties2016In: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344, Vol. 136, p. 146-153Article in journal (Refereed)
    Abstract [en]

    In this study, new wood-inspired films were developed from microfibrillated cellulose and galactoglucomannan-lignin networks isolated from chemothermomechanical pulping side streams and cross-linked using laccase enzymes. To the best of our knowledge, this is the first time that cross-linked galactoglucomannan-lignin networks have been used for the potential development of composite films inspired by woody-cell wall formation. Their capability as polymeric matrices was assessed based on thermal, structural, mechanical and oxygen permeability analyses. The addition of different amounts of microfibrillated cellulose as a reinforcing agent and glycerol as a plasticizer on the film performances was evaluated. In general, an increase in microfibrillated cellulose resulted in a film with better thermal, mechanical and oxygen barrier performance. However, the presence of glycerol decreased the thermal stability, stiffness and oxygen barrier properties of the films but improved their elongation. Therefore, depending on the application, the film properties can be tailored by adjusting the amounts of reinforcing agent and plasticizer in the film formulation.

  • 24.
    Oinonen, Petri
    et al.
    KTH, Träkemi och massateknologi.
    Moriana, Rosana
    KTH, Träkemi och massateknologi.
    Krawczyk, Holger
    Ek, Monica
    KTH, Träkemi och massateknologi.
    Henriksson, Gunnar
    KTH, Träkemi och massateknologi.
    The composite formation of cross-linked galactoglucomannan-lignin networks and cellulose nanoparticles as defined by thermal and mechanical testingManuscript (preprint) (Other academic)
  • 25.
    Samuelsson, Lina N.
    et al.
    KTH Royal Institute of Technology.
    Bäbler, Matthaus U.
    KTH Royal Institute of Technology.
    Moriana, Rosana
    KTH Royal Institute of Technology.
    A single model-free rate expression describing both non-isothermal and isothermal pyrolysis of Norway Spruce2015In: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 161, p. 59-67Article in journal (Refereed)
    Abstract [en]

    A strictly isoconversional rate expression has been derived for pyrolysis of biomass. This rate expression, derived from non-isothermal thermogravimetric experiments using heating rates 2-10 K/min, can successfully predict the conversion rates of experimental data at heating rates 1-100 K/min and quasiisothermal experiments at 539-650 K. The methodology used is based on an extension of the incremental integral method by Vyazovkin (2001). Being able to derive an intrinsic reaction rate expression from non-isothermal data, without any assumption regarding the chemical processes present, opens up for the possibility to model industrial pyrolysis reactors, with a variety of temperature profiles.

  • 26.
    Samuelsson, Lina N.
    et al.
    KTH Royal Institute of Technology.
    Bäbler, Matthäus U.
    KTH Royal Institute of Technology.
    Brännvall, Elisabet
    KTH Royal Institute of Technology.
    Moriana, Rosana
    KTH Royal Institute of Technology.
    Pyrolysis of kraft pulp and black liquor precipitates derived from spruce: Thermal and kinetic analysis2016In: Fuel processing technology, ISSN 0378-3820, E-ISSN 1873-7188, Vol. 149, p. 275-284Article in journal (Refereed)
    Abstract [en]

    The potential of seven kraft cook materials to become functional char materials and fuels is investigated. Thermogravimetric analysis was used to study the thermal properties while a model-free isoconversional method was used to derive kinetic rate expressions. Black liquor precipitates had lower thermal stability (20-60 K lower) than pulps and spruce wood and the precipitates decomposed in a wider temperature range, producing chars with similar or higher thermal stability than char from pulps, but lower than those from spruce wood. Samples suitable to produce char were identified based on char yield, devolatilization rate and charring temperature. The highest char yield (46%), achieved from a precipitate, was more than twice as high as that from spruce powder. Under the studied conditions none of the materials had a pyrolysis process that for the whole conversion range could be described with a single set of kinetic parameters. The apparent activation energy varied between 170-260 kJ/mol for the pulps and 50-650 kJ/mol for the precipitates. The derived kinetic parameters were validated by predicting the conversion at a heating rate outside the range used for its derivation and at quasi isothermal conditions. Both these tests gave satisfactory results in good agreement with experimental data.

  • 27.
    Samuelsson, Lina Norberg
    et al.
    KTH Royal Institute of Technology.
    Moriana, Rosana
    KTH Royal Institute of Technology.
    Bäbler, Matthäus U.
    KTH Royal Institute of Technology.
    Ek, Monica
    KTH Royal Institute of Technology.
    Engvall, Klas
    KTH Royal Institute of Technology.
    Model-free rate expression for thermal decomposition processes: The case of microcrystalline cellulose pyrolysis2015In: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 143, p. 438-447Article in journal (Refereed)
    Abstract [en]

    We explore the possibility to derive a completely model-free rate expression using isoconversional methods. The Friedman differential method (Friedman, 1964) and the incremental integral method by Vyazovkin (2001) were both extended to allow for an estimation of not only the apparent activation energy but also the effective kinetic prefactor, defined as the product of the pre-exponential factor and the conversion function. Analyzing experimental thermogravimetric data for the pyrolytic decomposition of microcrystalline cellulose, measured at six different heating rates and three different initial sample masses (1.5-10 mg), revealed the presence of secondary char forming reactions and thermal lag, both increasing with increased sample mass. Conditioning of the temperature function enables extraction of more reliable prefactors and we found that the derived kinetic parameters show weak dependence on initial sample mass. Finally, by successful modeling of quasi-isothermal experimental curves, we show that the discrete rate expression estimated from linear heating rate experiments enables modeling of the thermal decomposition rate without any assumptions regarding the chemical process present. These findings can facilitate the design and optimization of industrial isothermal biomass fed reactors.

  • 28.
    Santonja-Blasco, L.
    et al.
    Instituto de Tecnología de Materiales, Universidad Politécnica de Valencia, Spain.
    Moriana, Rosana
    Instituto de Investigación en Tecnología de Materiales, Universidad Politécnica de Valencia, Spain.
    Badía, J. D.
    Instituto de Tecnología de Materiales, Universidad Politécnica de Valencia, Spain.
    Ribes-Greus, A.
    Instituto de Tecnología de Materiales, Universidad Politécnica de Valencia, Spain.
    Thermal analysis applied to the characterization of degradation in soil of polylactide: I. Calorimetric and viscoelastic analyses2010In: Polymer degradation and stability, ISSN 0141-3910, E-ISSN 1873-2321, Vol. 95, no 11, p. 2185-2191Article in journal (Refereed)
    Abstract [en]

    An accelerated soil burial test has been performed on a commercial polylactide (PLA) for simulating non-controlled disposal. Degradation in soil promotes physical and chemical changes in polylactide properties, which can be characterized by Thermal Analysis techniques. Physical changes occurred in polylactide due to the degradation in soil were evaluated by correlating their calorimetric and viscoelastic properties. It is highly remarkable that each calorimetric scan offers specific and enlightening information. Degradation in soil affects the polylactide chains reorganization. A multimodal melting behavior is observed for buried PLA, degradation in soil also promotes the enlarging the lamellar thickness distribution of the population with bigger average size. Morphological changes due to degradation in soil lead to an increase in the free volume of the polylactide chains in the amorphous phase that highly affected the bulk properties. Thermal Analysis techniques provide reliable indicators of the degradation stage of polylactide induced by degradation in soil, as corroborated by molecular weight analysis. © 2010 Elsevier Ltd. All rights reserved.

  • 29.
    Santonja-Blasco, Laura
    et al.
    Instituto de Tecnología de Materiales, Escuela Técnica Superior de Ingeniería del Diseño,Universidad Politécnica de Valencia, Spain.
    Contat-Rodrigo, Laura
    Instituto de Tecnología de Materiales, Escuela Técnica Superior de Ingeniería del Diseño,Universidad Politécnica de Valencia, Spain.
    Moriana-Torró, Rosana
    Instituto de Tecnología de Materiales, Escuela Técnica Superior de Ingeniería del Diseño,Universidad Politécnica de Valencia, Spain.
    Ribes-Greus, A.
    Instituto de Tecnología de Materiales, Escuela Técnica Superior de Ingeniería del Diseño,Universidad Politécnica de Valencia, Spain.
    Thermal characterization of polyethylene blends with a biodegradable masterbatch subjected to thermo-oxidative treatment and subsequent soil burial test2007In: Journal of Applied Polymer Science, ISSN 0021-8995, E-ISSN 1097-4628, Vol. 106, no 4, p. 2218-2230Article in journal (Refereed)
    Abstract [en]

    The viability of producing environment-friendly blends of HDPE and LDPE with a commercial biodegradable masterbatch containing starch and polyethylene was studied. The service life of these blends was simulated by means of a thermo-oxidative treatment, and their further disposal in landfill was modeled using an accelerated soil burial test. Characterization was carried out in terms of their calorimetric and thermogravimetric properties. Thermo-oxidative treatment causes an increase in the crystalline content of both components of the blends, and promotes a segregation of the crystallite sizes of polyethylene. The soil burial test leads to changes in the crystalline content of the biodegradable material, which is influenced by the polyolefinic matrix used. The kinetics of the thermal decomposition of these blends was studied using the Hirata and the Broido models. Thermogravimetric results reveal that the thermo-oxidative treatment causes a decrease in the activation energy of the thermal decomposition process of both components in the blends, regardless of the type of polyethylene used. The thermooxidative treatment mainly modifies the thermal properties of starch during the degradation process in soil, especially in the LDPE blends. Synergetic degradation of these blends is a complex process that is dependent on the polyolefinic matrix used and mainly causes morphological changes.

  • 30.
    Svärd, Antonia
    et al.
    Fiber and Polymer Technology, KTH Royal Institute of Technology, Stockholm, Sweden.
    Moriana, Rosana
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. Fiber and Polymer Technology, KTH Royal Institute of Technology, Stockholm, Sweden.
    Brännvall, Elisabet
    RISE Bioeconomy, Stockholm, Sweden.
    Edlund, Ulrica
    Fiber and Polymer Technology, KTH Royal Institute of Technology, Stockholm, Sweden.
    Rapeseed Straw Biorefinery Process2019In: ACS Sustainable Chemistry & Engineering, ISSN 2168-0485, Vol. 7, no 1, p. 790-801Article in journal (Refereed)
    Abstract [en]

    A rapeseed straw biorefinery process was demonstrated with more than 50% of the straw recovered as products. Xylan with a weight-average molecular weight of 56 760 g/mol was extracted in an alkaline step. The straw residue was subjected to soda pulping, resulting in cellulose-rich fibers and a lignin-rich liquid fraction. The lignin contained syringyl and guaiacyl aromatic structural units in a 1/0.75 ratio. The cellulose pulp was bleached, resulting in a cellulose fraction of 85% purity and a crystallinity index (CI) of 83%. Two grades of nanocellulose, CNF and CNC, were isolated from the bleached pulp. The CNF was very heterogeneous in size with an average diameter of 4 nm and an average length of 1177 nm. The CNC had an average diameter of 6 nm and an average particle length of 193 nm. CNF and CNC had good thermal stability and an aspect ratio of 294 and 32, respectively.

  • 31.
    Tagami, Ayumu
    et al.
    KTH Royal Institute of Technology, Department of Fibre and Polymer Technology, Stockholm, Sweden / Nippon Paper Industries Co., Ltd., Research Laboratory, Oji, Kita-ku, Tokyo, Japan.
    Gioia, Claudio
    KTH Royal Institute of Technology, WWSC-Wallenberg Wood Science Centre, Stockholm, Sweden / University of Bologna, Department of Civil, Chemical, Environmental, and Materials Engineering, Bologna, Italy.
    Lauberts, Maris
    Latvian State Institute of Wood Chemistry, Riga, Latvia.
    Budnyak, Tetyana
    KTH Royal Institute of Technology, Department of Fibre and Polymer Technology, Stockholm, Sweden.
    Moriana, Rosana
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. KTH Royal Institute of Technology, Department of Fibre and Polymer Technology, Stockholm, Sweden / SLU-Swedish University of Agricultural Sciences, Molecular Sciences, Uppsala, Sweden.
    Lindström, Mikael E.
    KTH Royal Institute of Technology, Department of Fibre and Polymer Technology, Stockholm, Sweden.
    Sevastyanova, Olena
    KTH Royal Institute of Technology, Department of Fibre and Polymer Technology, Stockholm, Sweden / KTH Royal Institute of Technology, WWSC-Wallenberg Wood Science Centre, Stockholm, Sweden.
    Solvent fractionation of softwood and hardwood kraft lignins for more efficient uses: Compositional, structural, thermal, antioxidant and adsorption properties2019In: Industrial crops and products (Print), ISSN 0926-6690, E-ISSN 1872-633X, Vol. 129, p. 123-134Article in journal (Refereed)
    Abstract [en]

    This work summarizes the impact of solvent fractionation on the chemical structure, antioxidant activity, heating values, and thermal and adsorption properties of industrial hardwood and softwood kraft lignins. The aim of the research was to develop a simple approach for obtaining lignin fractions with tailored properties for applications in certain materials. Four common industrial solvents, namely, ethyl acetate, ethanol, methanol and acetone, in various combinations, were found to be efficient for separating spruce and eucalyptus kraft lignins into fractions with low polydispersities. The ethanol fraction of spruce and the ethyl acetate fraction of eucalyptus afforded the highest yields. Gel-permeation chromatography analysis was used to evaluate the efficiency of the chosen solvent combination for lignin fractionation. The composition and structure of the lignin material was characterized by elemental analysis, analytical pyrolysis (Py-GC/MS/FID) and 31P NMR spectroscopy. The thermal properties of the lignin samples were studied using thermogravimetric analysis. Proximate analysis data (ash, volatile components, organic matter and fixed carbon) was obtained through the direct measurement of weight changes in each experimental curve, and the high heating values (in MJ/kg) were calculated according to equations suggested in the literature. The adsorption properties of fractionated kraft lignins were studied using methylene blue dye. The correlations observed between molecular weight, composition and functionality and the thermal, radical scavenging and adsorption properties of the lignin fractions provides useful information for selecting the appropriate solvent combinations for specific applications of lignin raw materials (including their use as antioxidants, biofuels or sorbents in water treatment processes). © 2018

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