Polyhedral oligomeric silsesqioxanes (POSS) compounds consisting of [RSiO3/2](n) groups organized in the form of various polyhedra (T-n, n =3, 6, 8, 10, 12, ....) have not often been used as pigment surface modifiers. Their interactions with pigments are not known in detail and coatings deposited from pigments modified by POSS dispersants are rare. Identification of interactions between a dispersant and the surface of pigments is important from the point of view of obtaining stable pigment dispersions enabling the deposition of optical coatings with high pigment loading, low haze and mechanical integrity. Thin TiO2 (anatase) pigment coatings (70-260 nm) were deposited from pigment dispersions prepared by milling metatitanic acid (mTiA) powder agglomerates with trisilanol heptaisobutyl silsesquioxane dispersant (trisilanol POSS) in butanol and hexane. The results of TEM, EDAX and TG measurements confirmed the influence of trisilanol POSS dispersant on the formation of a dispersion with a uniform distribution of mTiA and rutile (mTiR) nanoparticles with a size of about 30 +/- 5.0 nm and 90 +/- 5.0 nm, respectively, as determined from dynamic light scattering (DLS) measurements. The mTiA/trisilanol POSS dispersions with added titanium tetraisopropoxide were deposited on fluorine-doped tin oxide (FTO) coated glass (spin-coating) and indium tin oxide coated polymeric substrate (ITO PET) (coil-coating) and thermally treated at 150 degrees C. UV-vis spectra, AFM and SEM results showed that the pigment coatings exhibited low haze (up to 6%), low surface roughness (up to 20 nm) and uniform morphology. mTiA/trisilanol POSS interactions were assessed from the frequency shifts of the Si-O-Si stretching modes of trisilanol POSS, while the adsorption of the dispersant was followed from the intensity changes of the corresponding -CH3 and -CH2 stretching modes, confirming the gradual occupation of the mTiA crystalline sites by trisilanol POSS dispersant. Examination of IR vibrational spectra showed that trisilanol POSS interacted with the mTiA surface by establishing hydrogen bonding. The advantage of using trisilanol POSS dispersant was demonstrated by the enhanced electrochromic effect of the mTiA pigment coatings. (C) 2014 Elsevier B.V. All rights reserved.