Study on bonding ability of melt-spun polypropylene/polyethylene blend fibers

This article investigates melt spinning of polypropylene (PP) with high-density polyethylene (HDPE) and linear low-density polyethylene (LLDPE) blend fibers at different compositions, as well as the effects of HDPE and LLDPE on the bonding ability of blend fibers in thermal bonding process at different temperatures have been studied. HDPE and LLDPE were added to PP at 3, 5, 7, and 10 wt% to measure the upper threshold of such blends. While HDPE was added up to 7 wt%, PP/LLDPE blend fibers were only spun up to 3 wt% of LLDPE. Differential scanning calorimetry (DSC) revealed that increasing both HDPE and LLDPE contents lead to higher crystallinity values due to polyethylenes nucleating effect on PP. By adding HDPE and LLDPE, the tensile strength of blend fibers before and after bonding was decreased drastically compared to pure PP fibers. On the other hand, the addition of HDPE to PP and increasing bonding temperature enhanced bonding strength.