PURPOSE:Hulls, stems, branches and leaves of true grasses are made into fine powders, which are added to various kinds of synthetic macromolecular substances to improve the physical and other properties and simultaneously lower the costs. CONSTITUTION:Hulls, stems, branches and leaves of true grasses as rice hulls are made into fine powders and added to various kinds of macromolecular substances as synthetic resin, rubber, coating or adhesive to give said product. For example, a powder of rice hull is mixed with polypropylene and molded into pans for growing seedlings, which have increased heat resistance, tensile strength compared to the moldings containing no hull powder. When a polyvinyl chloride containing rice hull powder is formed into bases for applying wall paper, the bases have better heat insulation, sound insulation and flame retardancy. The addition of the composition to mosquito-repellent incense prolongs the burning time.
