Fuente: Journal of applied polymer Lugar: RESEARCH ARTICLE A novel strategy combining melt electrospinning and gel spinning fabricates polyethylene composite fibrous mats. Subsequent hot-stretching induces oriented crystallization and promotes the transformation from folded-chain crystals to extended-chain crystals, which yields composite fibrous mats with excellent mechanical properties and expands the range of materials processable by melt electrospinning.

ABSTRACT
Melt electrospinning has attracted interest as an efficient technology with industrial potential. However, challenges such as low efficiency and insufficient fiber refinement arise when processing high-viscosity melts. This study therefore proposes combining traditional polyethylene (PE) gel spinning with melt electrospinning to manufacture high-performance PE fibrous mats. First, linear low-density polyethylene (LLDPE) and ultrahigh molecular weight polyethylene (UHMWPE) were blended into a PE gel. Then, the composite fibrous mats were prepared via melt electrospinning and hot stretching processes. Rheological and Raman analyses revealed that a composite fibrous mat containing 33 wt% LLDPE and 1.0 wt% UHMWPE exhibited optimal polymer compatibility and dispersion, resulting in the formation of a uniform physically entangled network. Hot stretching promotes stress-induced lamellar rearrangement and molecular-chain orientation, resulting in enhanced crystallinity, molecular orientation, and mechanical properties. At a draw ratio of 4, the stress of the composite fibrous mat increased from 17 MPa in the unstretched state to 54 MPa. This method overcomes the limitations of processing PE via melt electrospinning and provides a new approach for processing polymers with similar rheological properties.