Cotton nonwovens with unidirectional water-transport properties produced by atmospheric plasma deposition

Cotton based nonwovens with unidirectional water-transport through the thickness of the fabric were prepared using atmospheric plasma technology. In controlling the plasma deposition parameters, a thin layer of polymerized Hexamethyldisiloxane was locally deposited onto a cotton nonwoven fabric, so that only the treated surface was hydrophobic, while the untreated surface remained hydrophilic. The water contact angle, surface morphology and chemical composition of the fabric surfaces were characterized, and the unidirectional water-transport performance, vapor transmission rate, thermal stability and durability of the treated nonwovens were tested. It was found that a super-hydrophobic surface could be durably achieved on one side of the fabric while maintaining a completely wettable surface on the other. The resulting asymmetric wettability enables the nonwovens to exhibit unidirectional water liquid-transport, without negatively affecting vapor transmission and air permeability. Such differential moisture management properties in sustainable cotton nonwovens are highly desirable for applications in hygiene, infection control and medical device applications.