Response of air drag force of the polyethylene terephthalate (PET) yarn treated via dielectric barrier discharge (DBD) plasma to its varying surface characteristics

In this paper, non-thermal plasma induced by dielectric barrier discharge (DBD) air discharging was used to treat the moving polyethylene terephthalate (PET) yarn samples and the motionless samples, respectively. The air drag force of the resultant samples was tested, and their surface characteristics were analyzed by X-ray photoelectron spectroscopy (XPS) for chemical composition and by scanning electron microscopy (SEM) for microscopic morphology. The results of the drag force of the samples indicated that, compared with the pristine yarn, the drag force of the samples treated via the two types of plasma treatment clearly varied under different processing conditions. The maximal drag force was 28.26cN for the moving sample treated at 34 V control voltage for 30 s in the discharge zone (zone A) and 27.81cN for the motionless sample treated at 36 V control voltage for 60 s in the long-lived plasma species treating zone (zone B), which increased by 18.9% and 17.0% over that of untreated sample (23.77cN), respectively. The fluctuation of the drag force probably depends on the change of the chemical composition and microstructure of the polyethylene terephthalate yarn surface, which implies that the feasibility of weaving efficiency improvement for an air-jet loom could be realized via controlling and optimizing the dielectric barrier discharge operating conditions.