4 documents found, page 1 of 1
Extração e caracterização de hemiceluloses de Pinus radiata e sua viabilidade p...
Reyes,Pablo; Mendonça,Regis Teixeira; Aguayo,María Graciela; Rodríguez,Jaime; Vega,Beatriz; Fardim,PedroAs galactoglucomananas são as principais frações de hemiceluloses presentes nas madeiras moles e contêm, principalmente, as hexoses galactose, glicose e manose. O isolamento eficiente e seletivo dessas hemiceluloses é um obstáculo crítico a superar para sua utilização. Os objetivos deste trabalho foram extrair e caracterizar soluções aquosas ácidas e neutras de hemiceluloses de cavacos de madeira de Pinus radia...
Effects of kraft pulping on the interfacial properties of Eucalyptus pulp fibres
Fardim,Pedro; Durán,NelsonThe effects of kraft pulping on the interfacial properties of eucalypt pulp fibres were investigated using polyelectrolyte titration (PT) and contact angle measurements. Changes on surface composition were assessed by FTIR-ATR spectrometry combined with principal component analysis (PCA). Surface lignin was removed by increase in active alkali in pulping as indicated by FTIR-ATR and PCA. In parallel, the surfac...
Influences of surface chemical composition on the mechanical properties of pulp...
Fardim,Pedro; Durán,NelsonThe effects of bulk and surface chemical composition on the mechanical properties (MP) of eucalyptus kraft pulp were investigated using Liquid Chromatography (HPLC), Scanning Electron Microscopy (SEM), X-ray Photoelectron Spectroscopy (XPS) and Principal Component Analysis (PCA). SEM images of fractured regions during tear (TrID), tensile (TsID) and burst (BuID) tests of refined pulps showed fibre deformation a...
Retention of cellulose, xylan and lignin in kraft pulping of eucalyptus studied...
Fardim,Pedro; Durán,NelsonEffects of pulping variables on the retention of carbohydrates and lignin in fast kraft pulping of eucalyptus were investigated using a complete factorial design. Influences of pulp chemical composition on physicochemical and mechanical properties were evaluated using Principal Component Analysis. Active alkali (AA) significantly affected the macromolecular degradation of cellulose and retention of xylan and li...