| abstract |
A composite board having a sorghum stalk material component and a thermoplastic binder component is disclosed together with a corresponding method of manufacture. To prepare the composite board, the sorghum stalk material is harvested, dried and refined into fibers, particles or slit-stalks. In some cases, the stalk material is first combined with a thermosetting binder such PMDI. Next, the stalk material is arranged into one or more layers and then combined with a thermoplastic binder, such as HDPE film, in a stack. In some instances, recycled HDPE may be used. The stack is thermocompressed in a press at a preselected temperature to compress the sorghum and thermoplastic binder to a preselected board thickness. The board is then cooled to below the softening temperature of the thermoplastic resin. After cooling, the board can be cut or trimmed to its final desired dimensions. |