Wettability of Polyhedral Oligomeric Silsesquioxane Nanostructured Polymer Surfaces

Abstract

Summary: Some model structures of waterborne polyurethane anionomers containing various amounts (ca. 3–20%) of a diol functionalized polyhedral oligomeric silsesquioxane (POSS) nanofiller were prepared. X‐ray diffraction showed the formation of a nanocrystalline structure in all copolymers considered. Static contact angle measurements indicated a significant enhancement of surface hydrophobicity as well as reduction in surface tension components even at the least POSS level (3%). Dynamic contact angle cycles allowed the evaluation of the hysteresis, which was found to be large and kinetically increasing in POSS‐modified samples. Film topography was analyzed by AFM, showing a more pronounced roughness in the nanostructured surface.The AFM image showing a moderate roughness increase.magnified imageThe AFM image showing a moderate roughness increase.

Surface energetics, dispersion, and nanotribomechanical behavior of POSS/PP hybrid nanocomposites

“…These findings are consistent with previously reported studies showing increased surface hydrophobicity for other POSS/polymer systems and POSS molecules with fluorinated alkyl chains attached to the POSS cage. 12,[21][22][23][24] Surface dynamics were further studied via dynamic water contact angle analysis. The advancing (h a ) and receding (h r ) water contact angles were measured and their difference, the contact angle hysteresis (h h ), was calculated (Table 4).…”

“…Most of the studies reveal non-homogenously dispersed POSS crystalline aggregates ranging from a few hundred nanometers to several microns. 6,18 Recently, studies on surface properties of POSS HPNC's have appeared in the literature, and these are focused mainly on the surface hydrophobicity of POSS based copolymers, 21,22 fluorinated POSS, 23 and fluorinated POSS/ fluorinated polymer composites. 24 All of these studies report increased hydrophobicity on incorporation of POSS nanoparticles.…”

Thermally reversible cross-linked poly(ether-urethane)s

“…In most of the cases the polar component's value was higher than the dispersive one's indicating that the dipolar forces and the hydrogen bonds played an important role in the structure of the polyurethanes and polyurethane networks. The value of the molar free energy of hysteresis was higher in ethylene glycol than that in water, in most of the cases, suggesting that the contribution of dipolar forces and hydrogen bonds in water was more pregnant in ethylene glycol [48].…”

The influence of POSS nanoparticles on selected thermal properties of polyurethane-based hybrids

“…In this series, POSS particles with different number and configuration of functional groups were used leading to a plurality of chain architectures. Turri et al [47,48] synthesized a linear ionomeric PU/ POSS nanocomposite through a diol-functionalized POSS macromer. More recently Huang et al [49,50] reported on systems based on natural resources, i.e., castor oil and soycastor oil, combined with isophorone diisocyanate and a double-decker POSS moiety.…”