In this study, the viability of acetylation in cellulose fibers waste (CFW) from pulp and paper mill sludge was investigated in comparison to bleached cellulose fibers (BCF). Four acetylation methodologies were applied. The inorganic ash composition of the CFW was determined by Energy Dispersive X-ray Spectrometry (EDS). The Degree of substitution (DS) of the acetylated fibers and their characterization using Fourier Transformed Infrared (FT-IR), X-ray diffraction (XRD), Thermogravimetric analysis (TGA), and Scanning electronic microscopy (SEM) were carried out. Results showed that the different acetylation methods are not effective for the esterification of CFW largely due to a high mineral content in their composition. The acetylation promoted the removal of the inorganic content in the CFW resulting in low efficacy levels. In BCF, higher efficiency levels were achieved, varying according to the methods. The different acetylation methods showed an efficiency range from 0.02 to 1.76 depending on the type of fiber.

The objective of this work was to evaluate the feasibility of using lignin-phenol-formaldehyde resin in the production of Mimosa scabrella Benth (bracatinga) structural particleboard. The boards were produced with nominal specific mass of 0.75 and 0.95 g/cm³, 10% and 12% of phenol-formaldehyde and lignin-phenol-formaldehyde resins, with 10 and 12 min of pressing time. The boards quality was evaluated by means of the following physical-mechanical tests: specific mass, compression ratio, water absorption and thickness swelling after 2 and 24 hours soaking, perpendicular traction, static bending and screw pulling. Positive interactions of specific mass, resin content and pressing time were observed in the properties of the boards produced. The evaluation of the properties results based on the requirements of EN 312 (type P5) standard indicated the feasibility of using lignin-phenol-formaldehyde resin in the production of particleboard of Mimosa scabrellla for structural applications.

In this investigation, sludge fibre waste (SFW) and Kraft lignin powder (KLP) are introduced into polylactic acid (PLA) matrix biocomposites. These alternative materials allow for both the reuse of fibre waste from paper mill sludge and a reduction in the amount of high-cost biopolymer used in the same volume. Proportions from 10 to 40 wt.% of SFW with the addition of 2.5% and 5% of KLP are incorporated in PLA by extrusion and injection moulding. The thermogravimetric properties, water absorption, tensile and flexural properties, and morphology of the fabricated biocomposites were investigated. According to the results, KLP contributes to thermically stabilising the loss resulting from the incorporation of SFW. Flexural and tensile tests reveal a more pronounced decrease in strength with an SFW ratio above 10%. The modulus of elasticity increases significantly with an SFW ratio above 20%. The strength properties are stabilised with the addition of 5% KLP. The addition of KLP presents a tendency to reduce water absorption obtained by the incorporation of SFW into biocomposites. Scanning electron micrographs evidence that KLP improves the interfacial adhesion by reducing the voids between fibres and PLA.

O objetivo deste estudo foi avaliar a viabilidade técnica da utilização de cinco espécies de Eucalyptus, provenientes de plantios com ciclo de curta rotação, para produção de painéis OSB. As espécies estudadas foram: Eucalyptus benthamii, Eucalyptus dunni, Eucalyptus grandis, Eucalyptus saligna, Eucalyptus urograndis, a mistura entre elas e o Pinus taeda como testemunha. Os painéis de Eucalyptus apresentaram maior estabilidade dimensional quando comparados com os painéis testemunha. Os painéis compostos pelo mix de espécies apresentaram estabilidade dimensional semelhante aos demais produzidos com as espécies de Eucalyptus puras. No ensaio de flexão estática os valores de MOR não apresentaram diferenças estatísticas entre os tratamentos, porém, para MOE, os painéis de Eucalyptus apresentaram valores estatisticamente superiores quando comparados aos da testemunha. Na tração perpendicular os painéis produzidos com Pinus taeda apresentaram valor médio superior às demais espécies. Todas as espécies assim como a mistura entre elas mostraram viabilidade técnica para produção de painéis OSB.

The objective of this study was to evaluate the technical feasibility of the use of five Eucalyptus species, originating from plantations with short rotation cycle, for particleboards manufacture. The following species have been studied: Eucalyptus benthamii, Eucalyptus dunni, Eucalyptus grandis, Eucalyptus saligna, Eucalyptus urograndis, their mixture and Pinustaeda as a control. 21 wood particleboard have been produced, with nominal density of 0.65 g/cm³, totaling 7 treatments. For the bonding, urea-formaldehyde resin was used, in the proportion of 8% of solids dry weight base of the particles, 2% of catalyst ammonium sulphate on weight of resin and 1% of paraffin. The Eucalyptus particleboards showed lower values of WA2h and WA24h than the particleboards produced with Pinus taeda. The particleboards composed Mix of species exhibited high dimensional stability similar to those produced with the pure Eucalyptus species. E. grandis showed values statistically higher of mechanical resistance (MOR and MOE) to those obtained by the other species studied, as well as, the Eucalyptus species were higher than the control species. In internal bond the particleboards produced with E. grandis was among the highest results of internal bond, being statistically similar to E. saligna. The species Mix particleboards exhibited proprieties in general similar to those produced with the pure Eucalyptus species. All species as well as the mix among them showed technical feasibility for particleboard manufacture.

O presente trabalho teve por objetivo caracterizar e avaliar o processo de fabricação de portas a partir de cartas de controle de variáveis.