Role of the Relaxation State of Polymer Components in Wood When Making Composite Packaging Materials (Corrugated Cardboard)

详细

We consider targeted variation of the relaxation state for polymer components of wood in stages of the life cycle of corrugated cardboard. From the standpoint of the structural physicochemistry of wood, we present a mechanism for the processes occurring in traditional corrugated cardboard production technology. Our thesis is that cellulose and hemicellulose can go from the glassy state to the rubbery (highly elastic) state at 220°C, but under real conditions this transition occurs at room temperature and even at negative temperatures in the case of plasticization by a sufficient amount of water. Transition of lignin from the glassy state to the rubbery state occurs at a temperature above 130°C, and at 70°C-120°C under conditions of sufficient hydration. Formation of strong interfiber bonds is possible only when the polymers forming the contact are in the rubbery or viscous-flow state.