| 摘要 |
<p>PURPOSE: To obtain an impervious sheet used in the final waste disposition which is obtained by adding an ultraviolet absorber and carbon black to a thermoplastic polyurethane specified in its average molecular weight and shows excellent scratch resistance regardless of the environmental temperature and can be surely jointed fusing with high durability. CONSTITUTION: The starting material for the sheet is prepared by adding (A) an ultraviolet absorber such as 2,2',4,4'-tetrahydroxybenzophenone, (B) carbon black as a reinforcing agent to (C) a thermoplastic polyurethane with an average molecular weight of 100,000-200,000. The component C is desirably obtained by reaction between a polyol bearing 2 or more active hydrogen atoms and a polyisocyanate. As a polyol, is preferred a polyether-polyol from the view points of the resistance to hydrolysis, flexibility and resistance to biodegradation. In a preferred embodiment, the amount of the component A is 0.1-1wt.%, while the component C is 2-10wt.%.</p> |
