Poly brushes contact angle

We reported the synthesis of Si/Si02//PS-h-poly(acrylate) tethered diblock copolymer brushes [31,32,46,47]. The properties of these diblock brushes were studied using water contact angles, ellipsometry. X-ray photoelectron spectroscopy (XPS), FTIR spectroscopy and atomic force microscopy (AFM). For a sample with a 26 nm PS layer and a 9 nm PMMA layer, the advanc-... 

Styrene) (PPFS), poly(heptadecafluorodecyl acrylate) (PHFA), poly(penta-fluoropropyl acrylate) (PPFA), or poly(trifluoroethyl acrylate) (PTFA) [53]. The block at the silicate interface was either PS or PMA. Treatment of the diblock systems with block-selective solvents produced predictable changes in water contact angles except for those diblock brushes based on PHFA. All of these systems were fully characterized by XPS, tensiometry, ellipsometry,... 

Figure 4. Water contact angle results for PS/Poly(PEGMA) segregated brushes influence of the solvent treatment.

Figure 4.9 Poly(N-methylvinylpyridiniym) brush on ETFE. Exchange of chloride or iodide counterions by per-fhiorooctanoate counterions. The water contact angle increases with immersion time as the counterion exchange proceeds. A steady state is reached after approximately 50s immersion in PFO solution.

The poly(MPC) brush gave a quite wettable surface. The contact angle of the water droplet (2.0 pL) on poly(MPC) brush surface was very low (below 5°). The contact angles of methylene iodide and hexadecane were 45° and <5°, respectively. Using the Owens-Wendt equation [49], the surface free energy of the poly(MPC) brush surface was estimated to be 73 mJ/m, which is quite similar to that of water. Therefore, water plays the role of a good solvent, resulting in low friction of the poly(MPC) brush. Ho et al. [50] prepared a low-friction surface on polyurethane... 

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