Effect of the type of plasma on the polydimethylsiloxane/collagen composites adhesive properties

• Published in: International journal of adhesion and adhesives Vol. 77; pp. 85 - 95
• Main Authors: Juárez-Moreno, J.A., Brito-Argáez, L.G., Ávila-Ortega, A., Oliva, A.I., Avilés, F., Cauich-Rodríguez, J.V.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.09.2017; Elsevier BV
• Subjects: Adhesion; Adhesion by chemical bonding; Adhesion by mechanical interlocking; Adhesion tests; Adhesive strength; Adhesives; Argon; Argon plasma; Atomic force microscopy; Composite; Contact angle; Fourier transforms; Functional groups; Infrared spectroscopy; Nitrogen; Nitrogen plasma; Oxygen; Oxygen plasma; Peel strength; Peel test; Plasma; Plasmas (physics); Polydimethylsiloxane; Properties (attributes); Scanning electron microscopy; Silicone resins; Surface properties; Surface roughness; Surface treatment by excited gases; Surface treatment by excited gases; Composite; Peel test; Adhesion by mechanical interlocking; Adhesion by chemical bonding
• ISSN: 0143-7496; 1879-0127
• DOI: 10.1016/j.ijadhadh.2017.03.010

Polydimethylsiloxane (PDMS) films were treated with either oxygen (O2), nitrogen (N2) or argon (Ar) plasma between 40W and 120W for 5–15min and their surface properties studied by contact angle measurements, infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and atomic force microscopy (AFM). Lower contact angles and increases in surface roughness, assessed by SEM and AFM, were observed for all used gases when plasma power and time increased, with argon treatment being the one that showed the most significant change in roughness. PDMS/collagen type I composites obtained after treating PDMS with oxygen at 80W for 13min or nitrogen and argon at 80W for 14min showed a peel strength of 0.1N/mm (oxygen plasma), 0.08 N/mm (nitrogen plasma) and 0.09 N/mm (argon plasma). In all cases, peel strength was higher than that measured for the untreated bilayer composite. An increase in adhesion strength, after oxygen and nitrogen plasma, was mostly attributed to chemical interaction between functional groups introduced on the PDMS surface and the functional groups on collagen as detected by FTIR. In contrast, the high peel strength observed on PDMS treated with argon plasma was attributed to its increased roughness which in turn increased mechanical interlocking. The properties of these composites render them suitable for adhesive free skin substitutes.