| 摘要 |
An extruded polycarbonate multi-walled sheet structure includes at least two and in some cases seven or more generally parallel spaced apart walls and a plurality of ribs extending the length of the sheet in a direction of extrusion and separating adjacent walls. The sheet structure has a total thickness greater than 40 mm and the polycarbonate has a melt viscosity ratio greater than about 4.5 measured at 260° C. wherein the melt viscosity ratio is a ratio of the viscosity at a shear rate of 100 s-1 to the viscosity at a shear rate of 0.1 s-1. |
