Oligomeric Poly(ethylene oxide)-Functionalized Silsesquioxanes: Interfacial Effects on T_g, T_m, and ΔH_m

Polyethyene oxide (PEO) oligomers (CH3−(O−CH2CH2)n−, where n = 2, 4, 〈8〉, and 〈12.5〉, and the brackets denote Mn averages) have been attached to Q8M8H silsesquioxanes to form Q8M8PEO(n). The effect of the inorganic interface is to raise the glass transition temperature, Tg, and suppress the crystallization of the PEO oligomers. With increasing n, Tg increases, and the PEO becomes semicrystalline, suggesting that PEO segments close to the interface remain amorphous.