Effect of Polyethylene Film Lamination on the Water Absorbency of Hydrophilic-finished Polypropylene Non-woven Fabric

Polyethylene/Polypropylene (PE/PP) composite non-woven fabrics have been used widely for surgical packages due to its dual features of PE surface and PP surfaces. PP fabric pre-treated by hydrophilic agent provides high water absorbency, while PE surface is responsible for high barrier functions. However, the PP water absorbency declines once PE film is laminated, and no report devoted to study the extent and the reasons of this declining. Herein, the hydrophilic finishing of the PP non-woven fabrics was processed via Kiss-roll method, then the PE/PP fabrics were obtained using a normal hot melt adhesive PE film laminating process. The wicking height, water absorption specific gravity (LAC%), static contact angle, as well as the complete wetting time of the finished PP and PE/PP fabric were measured and compared. Meanwhile, the SEM was used to detect the morphology changing. The results revealed that the pores between fibers in the PP non-woven were filled with non-hydrophilic hot melt adhesive penetrated during PE lamination, so that the PP structure changed to be less porous. Moreover, the laminated PP layer actually blocks the water flow channel in the system, resulting in the absorbency reduction after lamination. As a result, comparing with the PP non-woven fabric, the wicking height of the PE/PP fabric decreased by 25.3 %, the LAC % value reduced by 40.83 %, and the complete wetting time extended from 0.29 s to 1.74 s.