| 摘要 |
PURPOSE:To obtain a foamed molding which is biodegradable, has weak caloric force when burnt and excels in breath-ability, hygroscopicity and heat insulation by mixing a powder of a natural cellulosic substance with a biodegradable foamed polyolefin resin molding. CONSTITUTION:A biodegradable foamed polyolefin resin molding containing 30-80wt.% powder of a natural cellulosic substance. Examples of the natural cellulosic substances include wood flour, straws, rice hulls, bagasses and banana fibers. The formed molding is decomposed by the enzyme produced by the contained natural cellulosic substance and is spontaneously degraded when it is placed in surroundings such as soil where bacteria are active, so that it can be easily subjected to waste disposal. Because the powder of the natural cellulosic substance contains usually about 7wt.% water, when a mixture prepared by adding it in an amount of 30-80wt.% to a polyolefin resin is expansion- molded by heating, the water can act as a blowing agent to give a foamed resin molding. When the water content of the natural cellulosic substance is low, or a high expansion ratio is desired, a blowing agent is combinedly used. |
