The reason is that on a number of extruded compound modification oilysludge, just one layer on the heatsealing layer blending, middle-tier also may be in a lower-cost.

• 原因是对多层共挤复合基材进行改性，只需在其一层热封层上进行共混改性，在中间层还可采用成本较低的树脂。