Effect of Gel Solution Concentration on the Structure and Properties of Gel-Spun Ultrahigh Molecular Weight Polyethylene Fibers

Abstract

The gel-spun ultrahigh molecular weight polyethylene (UHMWPE) fibers were prepared at the industrial production line with different gel solution concentration of 10–18 wt %. The effect of gel solution concentration on the structure and performance of UHMWPE fibers was studied by tensile testing, differential scanning calorimetry (DSC), wide-angle X-ray diffraction (WAXD), and small-angle X-ray scattering (SAXS). With the increase of gel solution concentration, the ultimate mechanical properties of UHMWPE fibers decreased while the melting temperature increased. And the increase of gel solution concentration made the crystallization and orientation of UHMWPE fibers become worse. Furthermore, the average length (⟨L shish⟩) and misorientation (B ϕ) of shish structure in UHMWPE fibers decreased with the increase of gel solution concentration.

Structural Evolution of UHMWPE Fibers during Prestretching Far and Near Melting Temperature: An In Situ Synchrotron Radiation Small‐ and Wide‐Angle X‐Ray Scattering Study

“…Due to the excellent characteristics of ultrahigh molecular weight polyethylene (UHMWPE) fibers, including low density, high specific strength, and high chemical resistance, they have been widely used in high‐tech fields, such as military equipment, safety protection, and marine industry applications . Generally, UHMWPE fibers are fabricated through the gel‐spinning process, which consists of the following main steps: (1) preparation of the semidilute UHMWPE solution (swell process); (2) extrusion‐spinning to form jelly filaments; (3) and ultradrawing, including cold drawing (prestretching) followed by paraffin oil extraction and subsequent hot drawing (poststretching) of the extracted fibers . After spinning, the precursor fibers are composed of nearly isotropic folded‐chain crystals, which are transformed into oriented shish‐kebab crystals during prestretching and, finally, into extended‐chain fibrils during postdrawing .…”

The effect of shrinkage on the structure and properties of ultra‐high molecular weight polyethylene fibers with different concentration

“…UHMWPE chains are easy to enter crystal lattice under the effect of interfacial tension, which causes the shrinkage. But the UHMWPE gel fiber with high concentration has high solid content and high molecular chain entanglement points density 17,25,28–30 . High solid content reduces the interface of UHMWPE‐paraffin oil and chain entanglement points hinders the movement of UHMWPE chain segments.…”

“…The difficulty of shish structure formation is different in different concentration of gel‐spinning system. The formation of shish structure easily occurs in UHMWPE fiber with low concentration due to less hinderance from chains entanglement point 17 …”

Rheological behavior and flow instability in capillary extrusion of ultrahigh‐molecular‐weight polyethylene/high‐density polyethylene/nano‐SiO2 blends

“…With excellent mechanical strength, wear resistance, self‐lubricating, and low temperature resistance, ultrahigh‐molecular‐weight polyethylene (UHMWPE) fibers have been widely used in aerospace, military, medical, industrial protection, and other fields . To reach a higher draw ratio in the fiber, the UHMWPE molecular chains must have a low entanglement density to allow for molecular chain orientation during drawing .…”