Mechanisms of atmospheric pressure plasma treatment of BOPP

© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Surface energy increase of polymers with plasma treatment is an industrially significant process. The mechanisms behind this process are little understood, with work addressing the water contact angle decrease with treatment and changes in surface chemistry. Work presented here addresses the mechanism of this surface energy increase, by using crystalline biaxially orientated polypropylene (BOPP) films to identify plasma induced structural changes. Increased crystallinity of the BOPP films were observed by ATR-FTIR spectroscopy, indicating preferential oxidation of amorphous regions of the BOPP films by the plasma. This crystal structure change correlates with XRD peak shifts, implying relaxation of crystal regions into regions previously occupied by amorphous BOPP. The trend in surface energy increases also correlates with the effective increase in crystallinity.

[1]  Y. Shlyapnikov,et al.  Diffusion-controlled polymer oxidation , 1989 .

[2]  R. F. Giese,et al.  The Hydrophilicity and Hydrophobicity of Clay Minerals , 1995 .

[3]  J. Cambronne,et al.  Electrical model and analysis of the transition from an atmospheric pressure Townsend discharge to a filamentary discharge , 2005 .

[4]  M. Wertheimer,et al.  Plasma surface modification of polymers for improved adhesion: a critical review , 1993 .

[5]  Dongping Liu,et al.  Large-area and uniform surface modification of polymers by barrier discharge plasmas , 2011 .

[6]  G. Socrates,et al.  Infrared characteristic group frequencies : tables and charts , 1994 .

[7]  M. Chaudhury,et al.  Interfacial Lifshitz-van der Waals and polar interactions in macroscopic systems , 1988 .

[8]  R. Brandenburg,et al.  Diffuse barrier discharges in nitrogen with small admixtures of oxygen: discharge mechanism and transition to the filamentary regime , 2005 .

[9]  Michael R. Wertheimer,et al.  Surface degradation and hydrophobic recovery of polyolefins treated by air corona and nitrogen atmospheric pressure glow discharge , 2004 .

[10]  Luis Rogerio de Oliveira Hein,et al.  Study of polypropylene surface modification by air dielectric barrier discharge operated at two different frequencies , 2013 .

[11]  A. Chiper,et al.  Argon Versus Helium Dielectric Barrier Discharge for Surface Modification of Polypropylene and Poly(methyl methacrylate) Films , 2013, Plasma Chemistry and Plasma Processing.

[12]  D. Sawtell,et al.  Mass Spectrometric Observations of the Ionic Species in a Double Dielectric Barrier Discharge Operating in Nitrogen , 2016 .

[13]  N. McIntyre,et al.  Study of ultraviolet light and ozone surface modification of polypropylene , 1999 .

[14]  G. G. Stokes.  "J." , 1890, The New Yale Book of Quotations.

[15]  M. Kushner,et al.  A model for plasma modification of polypropylene using atmospheric pressure discharges , 2003 .

[16]  W. Hawkins,et al.  The morphology of semicrystalline polymers. Part I. The effect of temperature on the oxidation of polyolefins , 1959 .

[17]  J. L. Riley,et al.  Density, crystallinity, and heptane insolubility in isotactic polypropylene , 1959 .

[18]  I. Radu,et al.  Biaxially Oriented Polypropylene (BOPP) Surface Modification by Nitrogen Atmospheric Pressure Glow Discharge (APGD) and by Air Corona , 2002 .

[19]  A. T. Jones,et al.  Crystalline forms of isotactic polypropylene , 1964 .

[20]  A. Hiltner,et al.  Relationship between biaxial orientation and oxygen permeability of polypropylene film , 2008 .