Transfer molding of bamboo

Plastics play a very important role in our lives. However, there are several problems as it depends much on underground resources such as oil. To overcome such problems, we are trying to produce plastic substitute from bamboo, which is considered a promising renewable resource. To make efficient use of the strong fiber structure of bamboo, we did not powder bamboo. To obtain basic data to apply molding methods used on plastics, such as extrusion, injection molding, the flow property of bamboo was examined by a capillary rheometer. The fluidity improved as its moisture content increased. This is probably because that the softening point of the main components of bamboo, namely cellulose, hemicellulose and lignin are lower with water. In addition, the direct observation of the flow showed that not only softening of bamboo but chemical changes of its components play a certain role in the flow mechanism. Oven-dried bamboo particle showed poor fluidity. However, it was possible to flow oven-dried bamboo as well. The qualities of extruded specimens also depend much on the moisture content of the raw material. The extruded material obtained from oven-dried bamboo was matrix state, while fiber cells and parenchyma cells were clearly observed on the cut surface of the specimens obtained from air-dried/high moisture content bamboo. Transfer molding was performed on bamboo particles and the result showed feasibility of using bamboo as plastic substitute.