Effect of blend on high-field characteristics of low-density polyethylene

We used two kinds of low-density polyethylene (LDPE) with different densities, 0.9174 and 0.9180 g/cm/sup 3/ to blend. Using those LDPEs, we prepared the two groups of specimens; Group 1 specimens were passed one time through the extruder, and Group 2 specimens were passed two times through the extruder. For Group 1 specimens,the DC breakdown strength, F/sub BDC/, of blended LDPE with a blend ratio of 50 wt% was a little lower than those of virgin LDPE at 30/spl deg/C but higher at 90/spl deg/C. For Group 2 specimens, the F/sub BDC/ is almost the same at 30/spl deg/C, 60/spl deg/C and 90/spl deg/C. The extrusion improved F/sub BDC/ of the blended LDPE. It did not affect the current density at 30/spl deg/C and 60/spl deg/C, but increased it at 90/spl deg/C. It also reduced the 1350 cm/sup -1/ IR absorption peak attributed to gauche conformation decrease.