Polymer grafting plasma treatment

An alternative photo-SIP approach was described by Kang and coworkers, where they used an argon plasma to oxidize alkylthiolate SAMs on planar gold [55]. The plasma treatment oxidized carboxy-terminated SAMs to peroxide moieties. UV irradiation in the presence of acryhc acid and allylpentafluorobenzene yielded ultra-thin graft layers of 6-7nm. The poly(acrylic acid) layers were found to adsorb Fe " ions from solution. This particular photoinitiation method yields low-density polymer brush films. 

Polyacrylic acid (PAA)—P2VP mixed brushes were prepared by a similar synthetic procedure, by grafting of carboxyl-terminated poly(ferf-butyl acrylate) (PtBuA) and P2VP. Afterwards, PtBuA was hydrolyzed in the presence of p-toluene sulfonic acid. The same strategy was employed to graft mixed PEL brushes on polymer surfaces. In this case plasma treatment was used to functionalize surface of polymer substrates. We introduced amino groups on the surface of PA-6 and PTFE by treatment of the polymer samples with NH3 plasma. Then the carboxyl terminated homopolymers were grafted step by step from the melt to the solid substrate via amide bonds. 

Through plasma treatment, grafing of monomers can also take place on the polymer surface. For example, monomers, e.g., tetrafluoroethylene or hexafluoroethane, can be grafted onto wool or polypropylene fibers ( ). This type of grafting can improve such tribological properties as low friction. 

Examples of postprocess systems under evaluation include surface oxidation using ozone, hydrogen peroxide, or nitric acid. Such approaches are used in the production of conductive blacks. Reaction with diazonium salts, plasma treatment, and polymer grafting are also under investigation. 

Turmanova, S. Minchev, M. Vassilev, K. Danev, G. Surface grafting polymerization of vinyl monomers on poly(tetrafluoroethylene) films by plasma treatment. J. Polym. Res. 2008,15 (4), 309-318. 

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