Water contact angle, segregated

As the use of aqueous base in the development step has been mandated, the wettability of resist films is very important and therefore water contact angles of polymer and resist films are measured often. The contact angle measurement can provide important information about surface segregation of blend films. 

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

For instance, surface segregation in water vapor of the blend films prepared with polystyrene-hZocfc-poly(L-glutamic acid) PS27-Zt-PGA2o improved the reorientation of the hydrophilic polypeptide block at the interface (Fig. 5.22).[129] Water contact angle measurements supported the surface enrichment of polypeptide segments as a... 

Figure 26.13 Surface segregation of cyclic poly(oxyethylene) (1.5kg/mol) from its blend with polystyrene by annealing in a high-humidity environment. Images of water drops are shown with then-contact angles above the as-spun-cast film (left) and after annealing (right).

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