Plasma-treated polymer surfaces

Static SIMS analysis of plasma treated polymer surfaces. 

Tamada Y, Ikada Y (1993) Cell adhesion to plasma-treated polymer surfaces. Polymer 34 2208-2212... 

A great deal of research has been focused on the evaluation of plasma polymers and plasma treated materials for blood and soft tissue contacting-applications (2,3). A number of studies have involved the physical adsorption or covalent attachment of a variety of biomolecules to various gas plasma-treated polymer surfaces (4,5). In such studies, however, the covalent immobilization is often assumed to take place through precursor groups formed at the biomaterial surface from ill-defined oxygen and nitrogen functionalities obtained directly from the plasma. 

Scanning electron microscopy (SEM) analysis of polymer surfaces treated for 60 s, which is significantly greater than the 15 s treatment times used in this study, could detect no observable morphological differences between untreated and plasma-treated polymer surfaces for magnifications up to x20,000 (5). 

The sessile droplet contact angle measurement is a simple and accurate method to obtain information pertinent to the surface energy of a sample. The Wilhelmy balance method, on the other hand, is a very useful method to investigate the surface dynamic aspect of a sample, which will be described in the following sections. The instability of some of plasma-treated polymer surface observed by the Wilhelmy balance method is also described in Chapter 30. 

Table 3 presents some examples of plasma-treated polymer surfaces prepared for biomedical applications [55]. Additional references on gas disdiarge-treated biomaterials are dted in the bibliography [1, 3,4, 55],... 

Rearrangement of Functional Groups of Plasma-Treated Polymer Surfaces by Contact Angle Measurements... 

Plasma treatment is one of most common and suitable surface modification techniques for polymeric materials. This treatment can selectively introduce certain functional groups at a polymer sur ce with little damage to the bulk of the polymer. However, it is known that a plasma-treated polymer surface loses its properties gradually with aging. One reasonable explanation for this phenomenon is that the nctional groups, introduced by plasma treatment, rotate or move away from the surface into the bulk. Thus the changing surface properties may reflect... 

In this study, the changes of water contact angles on plasma-treated polymer surfaces were investigated in detail, and the relationship between the rearraiigement of the surface functional groups and the viscoelasticity of the polymer was investigated. 

However, it has also been shown [33] that the very acid nature of an oxygen plasma treated polymer surface inhibits electroless plating unless the surface is neutralized with hydroxide before plating. 

Morra, M., Occhiello, E. and Garbassi, F., Dynamics of Plasma Treated Polymer Surfaces Mechanisims and Effects, Paper presented at The International Conference on Polymer-Solid Interfaces, Namur, Belgium, Sept. 1991... 

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