Web fabrication and characterization of unique winged shaped, area-enhanced fibers via a bicomponent spunbond process

Abstract

High surface area fibers are sought after for a variety of applications such as liquid and air filtrations, medical and biopharmaceutical applications. Typically, higher specific surface area is achieved by resorting to using smaller fibers. This paper focuses on the development of a new shaped bicomponent spunbond structure for achieving high surface area. The fibers used in the spunbond process comprise a sacrificial sheath polymer and the shaped core polymer. Nonwovens were directly produced by using these fibers in a spunbond process. The spunbond webs were mechanically bonded by high energy water-jets and subsequently, the sheath polymer was removed in a 6 wt% NaOH solution at 90 °C. The final fibers showed a unique cross-sectional shape having 32 flaps or wings held together with a reasonable backbone. We report the results for a variety of polymer combinations including PP, PET, PBT, and PLA as the core and PLA and EastONE^TM as the sheath. The fiber morphologies were observed by SEM and showed 7–12 micron of the minor and 12–21 microns of the major with various core polymers used. The surface area of these fibers was compared to those of other shaped fibers.