Preparation and properties of flash spun UHMWPE/HDPE blend fibers
Ultra-high relative molecular mass polyethylene/high-density polyethylene(UHMWPE/HDPE)blend fibers were prepared by blending UHMWPE with better mechanical properties with HDPE in order to improve the mechanical strength of flash spun fiber bundles via flash spinning method.The effects of UHMWPE introduction on the morphology,melt crystallization,ag-gregate structure and mechanical properties of the blend fiber bundles were investigated by scanning electron microscopy,differ-ential scanning calorimetry,X-ray diffraction and universal testing machine.The results showed that the viscosity of the solution increased and the diameter of the blend fiber bundles gradually increased with increasing the mass fraction of UHMWPE from 1%to 5%in the spinning solution when preparing HDPE/UHMWPE blend fiber bundles by flash spinning,and the spinning solution would be unable to spin due to excessive viscosity when the mass fraction of UHMWPE was 7%;the crystallinity and orientation degree of HDPE/UHMWPE blend fiber bundles decreased and the mechanical properties increased with the increase of UHM-WPE content;and the crystallinity and orientation degree of the blend fibers were 74.2%and 0.46,respectively,with a de-crease of 4.7%and 45.7%,and the tensile strength was 118.9 MPa,which was 84.9%higher than that of pure HDPE fiber bundles,when the mass fraction of UHMWPE was 5%in the spinning solution.
high-density polyethylene fiberultra-high relative molecular mass polyethyleneflash spinningaggregate struc-turemechanical properties