01977naa a2200289 a 450000100080000000500110000800800410001902200140006002400550007410000190012924501140014826000090026252011040027165000110137565000180138665000220140465000120142665300180143865300320145665300240148865300150151270000230152770000240155070000170157470000220159177300740161321695302024-11-27       2024    bl uuuu     u00u1 u    #d  a0277-38137 ahttps://doi.org/10.1080/02773813.2024.23030362DOI1 aBARBOSA, K. T.  aAcid-catalyzed Kraft lignin liquefaction for producing polyols and polyurethane foams.h[electronic resource]  c2024  aThis study investigates the use of acid-catalyzed lignin liquefaction for the production of polyols and polyurethane foams. The liquefaction process was carried out using a kraft lignin powder following a process similar to the Lignoboost® method, based on a previous study, with catalyst (sulfuric acid) weight contents of 0, 3 and 6wt.% in relation to the lignin. The PU foams were prepared by the free expansion method and analyzed by Fourier transform infrared spectroscopy (FT–IR), thermogravimetry (TG), differential scanning calorimetry (DSC), dynamic-mechanical analysis (DMA), as well as contact angle and apparent density evaluations. The effect of the catalyst concentration on yield, moisture content and molecular weight of the resulting polyols was assessed, and the optimal conditions were obtained for 6wt.%. FT– IR analysis indicated a suitable foam polymerization. The incorporation of an acid catalyst led to a more hydrophilic foam and a rigid cell structure, with thinner and more uniformly sized cells, as well as higher thermal stability and glass transition temperature.  aLignin  aSulfuric acid  aÁcido Sulfúrico  aLignina  aAcid catalyst  aBio-based polyurethane foam  aLignin-based polyol  aLignoboost1 aSILVA, S. H. F. da1 aMAGALHAES, W. L. E.1 aAMICO, S. C.1 aDELUCIS, R. de A.  tJournal of Wood Chemistry and Technologygv. 44, n. 1, p. 9-21, 2024.