Poly methyl solid surface tension

Kwok DY, Leung A, Lam CNC, Li A, Wu R, Neumann AW (1998) Low-rate dynamic contact angles on poly(methyl methacrylate) and the determination of solid surface tensions. J Colloid Interface Sci 206 44-51... 

Estimate the contact angle of liquid methylene iodine (with surface tension equal to 50.8 mN m ) on a solid PMMA (poly(methyl methacrylate)) surface. The molar volumes (in cm moU ) are 86.5 for PMMA (repeating unit) and 80.6 for the liquid. Compare the result to the experimental contact angle value, which is 41°. 

Estimate the surface tension of solid poly(methyl methacrylate) and its contact angle with methylene iodide (y = 50.8 mN/m). 

The present investigation describes the successful modification of the surface properties of polymeric solids by the adsorption of appropriate partially fluorinated compounds at polymer-air interfaces during the formation of the polymer surfaces. The extent of additive adsorption was foxmd to be dependent upon the molecular structure, fluorine content, and solubility of the additives in the solute—i.e., their organophilic-organophobic balance with respect to the solute. Certain effective additives were able to decrease the critical surface tension, of such polymers as poly(methyl methacrylate) and polyacrylamide to 20 and 11 dynes per cm., respectively. These low values correspond to surfaces containing closely packed CF2 and CF3 groups. 

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