Organic-inorganic polyurethanes with 3,13-dihydroxypropyloctaphenyl double-decker silsesquioxane chain extender

In this contribution, we reported the synthesis of organic-inorganic polyurethanes with polyhedral oligomeric silsesquioxane (POSS) in the main chains. Toward this end, 3,13-dihydroxypropyloctaphenyl double-decker silsesquioxane (DDSQ) was synthesized; this POSS diol was used as a chain extender to obtain hybrid polyurethanes with DDSQ in the main chains. By controlling the molar ratio of 3,13-dihydroxypropyloctaphenyl DDSQ to 1,4-butanediol (BDO), organic-inorganic polyurethanes were obtained with a content of DDSQ up to 48 wt%. The results of H-1 nuclear magnetic resonance spectroscopy (NMR) and gel permeation chromatography (GPC) showed that 3,13-dihydroxypropyloctaphenyl, DDSQ, can be successfully used as a chain extender to afford linear organic-inorganic polyurethanes. Differential scanning calorimetry (DSC) showed that the organic-inorganic polyurethanes displayed enhanced glass transition temperatures (T-g's) compared to control polyurethane; the T-g's increased with increasing content of DDSQ in the main chains. Compared to control polyurethane, the organic-inorganic polyurethanes displayed improved thermal stability in terms of thermogravimetric analysis (TGA). With the inclusion of DDSQ in the main chains, the organic-inorganic polyurethanes displayed enhanced surface hydrophobicity.