Bamboo composites

This report describes the research that has been performed by Wageningen Food & Biobased Research on the development of bamboo composites from Bamboo from Ethiopia. This research is part of the INBAR DUTCH-Sino program. Currently the industry in Ethiopia is producing bamboo panels and bamboo stick based products – blinds, tooth picks, incense sticks. Plastic composite panels would be a new option for bamboo products in Ethiopia. Based on existing knowledge of plastic composite production processes an overview of possible processes and plastics matrix material is given. Ideally, plastic waste streams from Ethiopia would be used as plastic matrix, however, the plastic polymer type of two major large waste streams, PET bottles and PE bags and foils is considered not suited as plastic matrix for plastic fibre composites. Lab-scale tests have been performed on fine and course residues from current bamboo stick industry (based on highland and lowland bamboos) and on milled samples from top, middle and bottom parts of highland and lowland bamboo. Injection moulded composites were produced base on 30wt% of bamboo combined with a commercial grade polypropene (67 wt%) and a commercial coupling agent (3 wt%). Mechanical testing results show that all types of bamboo sources can be used to produce composites. On average, the composites of highland bamboo had slightly lower mechanical properties than lowland bamboo. The bending stiffness of the fine and course residues was slightly lower than the unprocessed bamboo samples. However, differences are small. Some considerations and recommendations concerning the development of bamboo composite panels are made, highlighting the differences with the current bamboo stick industry in Ethiopia. Current industry is labour intensive and the process is robust, the processes can be halted and restarted at any moment, water content/dryness of the bamboo is not extremely critical. The production process for bamboo composites is capital intensive. The process should be run continuously to prevent losses on start-up and shut down. Moisture content of the fibres needs to be controlled, ideally production should be performed under climate controlled conditions in the work space.