Oxygen Cold Plasma Treatment to Improve Hydrophilicity of HDPE Pellets

Abstract:

We demonstrated the environmentally friendly method, Cold Plasma treatment with oxygen plasma gas, in order to introduce the polar groups into non-polar polymer. HDPE pellets were treated with cold plasma under the mixture of plasma gas and air at atmospheric pressure. After that, the treated samples were immediately subjected into the twin-screw extruder. Plasma treatment time, 30 seconds, 1 and 2 minutes, was studied. From the contact angle measurement, all treated samples showed lower contact angle value than the neat HDPE from 96.83° to 80.84° - 84.53° suggesting that the hydrophilicity of all treated samples were improved. The polar part of surface free energy (γ_s^p) of all treated samples increased from the neat HDPE from almost zero to 13.34-21.88 mN/m. ATR-FTIR results confirmed the increasing of γ_s^p value. It was due to the new oxygenated functional groups which were introduced into the non-polar polymer. Lastly, from SEM images, the roughness of cross-sectional area increased after plasma treatment which attributed to the incompatible between the polar component and the non-polar component.

• Periodical: Advanced Materials Research (Volume 747)
• Pages: 210-213
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.747.210
• Online since: August 2013
• Authors: Mintra Meemusaw, Rathanawan Magaraphan
• Keywords: Cold Plasma Treatment, HDPE, Hydrophilicity

References

[1] M. Ataeefard, S. Moradian, M. Mirabedi, M. Ebrahimi, S. Asiaban, Investigating the effect of power/time in the wettability of Ar and O2 gas plasma-treated low-density polyethylene, Prog. Org. Coat. 64 (2009) 482-488.

DOI: 10.1016/j.porgcoat.2008.08.011

[2] C.S. Ren, K. Wang, Q.Y. Nie, D.Z. Wang, S.H. Guo, Surface modification of PE film by DBD plasma in air, Appl. Surf. Sci. 255 (2008) 3421-3425.

DOI: 10.1016/j.apsusc.2008.09.064

[3] H. A. Gulec, K. Sarioglu, M. Mutlu, Modification of food contacting surfaces by plasma polymerization technique. Part1: Determination of hydrophilicity, hydrophobicity and surface free energy by contact angle method, J. Food. Eng. 75 (2006).

DOI: 10.1016/j.jfoodeng.2005.04.007

[4] N. De Geyter, R. Morent, C. Leys, L. Gengembre, E. Payen, Treatment of polymer films with a dielectric barrier discharge in air, helium and argon at medium pressure, Surf. Coat. Tech. 16-17 (2007) 7066-7075.

DOI: 10.1016/j.surfcoat.2007.01.008

[5] W.L. Lu, C.Y. Huang, M.L. Roan, Effect of plasma treatment on the degree of AAm grafting for high-density polyethylene, Surf. Coat. Tech. 172 (2003) 251-261.

DOI: 10.1016/s0257-8972(03)00337-2