Colagem alcalina de papéis produzidos com polpas ECF e TCF de eucalipto

• Ano de defesa: 2000
• Autor(a) principal: Monteiro, José Vieira
• Orientador(a): Oliveira, Rubens Chaves de
• Banca de defesa: Gomide, José Lívio , Colodette, Jorge Luiz , Barbosa, Luiz Claudio de Almeida , Silva, Cláudio Mudado
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Mestrado em Ciência Florestal
• Departamento: Manejo Florestal; Meio Ambiente e Conservação da Natureza; Silvicultura; Tecnologia e Utilização de
• País: BR
• Palavras-chave em Português: Papel; Colagem alcalina; Papel alcalino; Dímero de Alquil Ceteno (AKD); Celulose ECF; Celulose TCE; Eucalipto
• Palavras-chave em Inglês: Paper; Alkaline size; Alkaline paper; AKD; ECF pulp; TCE pulp; Eucaliptus
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::RECURSOS FLORESTAIS E ENGENHARIA FLORESTAL::TECNOLOGIA E UTILIZACAO DE PRODUTOS FLORESTAIS::TECNOLOGIA DE CELULOSE E PAPEL
• Link de acesso: http://locus.ufv.br/handle/123456789/3186

The objective of this study was to evaluate the behavior of alkaline size of ECF and TCF pulps, as well as develop a procedure for alkaline size in laboratory and the development o a methodology for the quantification of AKD alkaline size agent which is retained in the paper. The studies carried out in the evaluation of the behavior of the alkaline size were: variation in the furnish consistency (0,2%, 0,3% and 0,4%), variation in the paper formation consistency (0,016%, 0,033%, 0,066% and 0,3%), variation in the dosage of the AKD agent (0,15%, 0,30%, 0,45%, 0,60% and 0,75% based on pulp), photochemical aging of papers, water activity on papers and protection of pulp functional groups. The pulps showed significant differences in morphological characteristics, such as lumen diameter (φ) and fiber wall thickness, while no difference in fiber length were noticed. The physical characteristic, such as average length of the fibrous material, number of fibers per gram and fines content did not show significant differences among the pulps studied. On the other hand, characteristics such as coarseness and water retention value (WRV) showed significant differences. Both pulps (ECF and TCF) do not differ significantly as far as the chemical characteristics of α, β e γ - cellulose is concerned. The TCF pulp showed higher content of carboxylic groups. The methodology adjusted for the quantification of the AKD coating agent retained in the paper through gas chromatography, showed to be efficient with good results. Then consistency of furnish preparation of 0,4 % showed negative effects in the retention of mineral charge of mineral fillers and in the alkaline size development (Cobb test). The retention of mineral fillers is reduced as the formation consistency is increased but with tendency to stabilize, while the alkaline size development is significantly affected at furnishes consistencies below 0,1%. At laboratory level, the retention of the AKD alkaline size agent (retention chemical plus physical) did not surpass 36% and papers produced with TCF pulp presenting higher retention. On the other hand, statistical analysis demonstrated those papers from ECF and TCF pulps, within the same dosage level of AKD agent, showed the same development gain of hydrophobicity to the cellulose fiber. Also, at laboratory level, the ECF and TCF pulps did not show alkaline size development with dosages below 0,3% (based on pulp). ECF and TCF papers with internal sizing did not suffer influence by the length of exposure to UV-light. Among the papers with internal sizing, those of ECF pulp showed water activity, both for aged and non-aged papers. However, in the papers without internal sizing, the TCF paper showed higher water activity. Among the mathematical models, which were tested, the one that was adjusted to the experimentally observed data was the so-called G.A.B (Guggenheim-Anderson de Boer). The effect of hydroxyl groups in the pulp was less impressive in the retention of the AKD agent than the carboxylic groups. The effect of protection of carboxylic groups the TCF pulp showed a strong reduction in the retention of mineral charge.