Potůček, František Bending stiffness for handsheets made of a blend of secondary fibres and chemi-mechanical pulp from rapeseed straw / František Potůček, Martina Říhová. -- Obr., tab. -- Lit. - The aim of this study was to investigate bending stiffness characteristics for handsheets made of a blend of secondary fibres and chemi-mechanical pulp from rapeseed straw, in mass ratio of 3 : 1, and 1 : 1, with a basis weight of around 520 g·m‒2. To manufacture chemi-mechanical pulp, three cold processes, namely neutral sulphite, alkaline sulphite, and caustic soda, were applied under laboratory conditions. The chemi-mechanical pulping comprises four main operations, viz. chipping, grinding, leaching, and beating to 43–46 °SR (Schopper-Riegler degree). The chemi-mechanical pulp was characterized by its degree of polymerization which was measured in the range of 75 to 110 with respect to relatively great amount of low molecular substances presented in pulps prepared by cold pulping process. The results obtained showed that the addition of chemi-mechanical pulp to secondary fibres led to a decrease in the bending stiffness, bending modulus of elasticity in the region of reversible deformation, as well as in the maximum curvature in the region of reversible deformation, and in critical curvature in the region of plastic deformation. However, the bending modulus of elasticity and maximum curvature was found to be comparable with those measured for moulded fibre products in our previous studies.

In Acta Facultatis Xylologiae Zvolen : vedecký časopis Drevárskej fakulty. -- Zvolen : Technická univerzita vo Zvolene, 2015. -- ISSN 1336-3824. -- Roč. 57, č. 2 (2015), s. 89-95

I. Říhová, Martina
II. Acta Facultatis Xylologiae Zvolen : vedecký časopis Drevárskej fakulty. -- Roč. 57, č. 2 (2015), s. 89-95

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