Lignin plasticization to improve binderless fiberboard mechanical properties

Mechanical properties of binderless fiberboard are correlated to the hydrothermal history of the fibers during the board process. Water and temperature thickness gradients allow to calculate a gradient of T-Tg difference (Tg, local glass transition temperature, function of local water content; T, local temperature). This gradient explains the variation of mechanical properties within the thickness and in time. The in situ plasticization of lignin, which is supposed to increase the T-Tg difference, improves the macroscopic mechanical properties of fiberboards. (c) 2005 Society of Plastics Engineers.