|TITLE||New light weight material development using
recycled plaster and waste paper
(Joint Program to Promote Technological Development with the Private Sectors)
RITE-WAKABAYASHI LABORATORY, RITE-MIYAGINO LABORATORY
The gypsum board discharged from a market has a high rate disposed of waste, and recycling is needed. Our company has developed the sponge-like material (made from used paper foaming material) with cushioning properties from used paper materials.
@The purpose of this research and development is establishing the manufacturing method of a lightweight new material which uses used plaster and used paper as the main materials using this foaming-ized technology. If this material is developed, new demand will be expected as a low environmental load type material replaced with petrochemicals in the field of building materials, such as thermal insulation and sound isolation material, and weight shock absorbing material.
@This fiscal year we investigated the particle size distribution of plaster in order to verify of the mass-production nature based on the process which used the gelatin in the last fiscal year as the binder, verification of PVA (polyviny Alcohol) as a new binder, and the quality of the used gypsum. Furthermore, the fire-resistant test was carried out to check the physical properties of this material. The above-mentioned result, are follows.
@During mass production, there was no damage by the added plaster in mixing and kneading, foaming-ized processes, board-like fabrication processes, and all the dryness processes. The board-like material measured about 0.15 to 0.2 specific volume-density. In the research using the new binder (PVA), foaming capability is expected to be able to promote low weight compared with the conventional gelatin binder. Moreover, although the distribution of a particle size is near 10Êm in new plaster, as a result of investigating a particle size distribution of plaster, it has [ two, 5Êm and 100Êm, ] distribution and is not fixed from used plaster. The new separation method of used plaster is needed for stabilization of product physical properties. Furthermore, the result of a fire-resistant test shows the total calorific value is twice as much as the standard value. The fire-resistant standard was not fulfilled. It is necessary to make an additional fire-resistant agent to improve the performance of the product.
@The final price of this material, is 3 to 5 times more than the market price, therefore much more cost cuts are needed.