The effect of poly (titanium oxide) obtained by sol-gel method on the thermophysical properties of organic-inorganic interpenetrating polymer networks

We studied the thermophysical properties of the organic-inorganic interpenetrating polymer networks (OI IPNs) based on the cross-linked polyurethane (PU), poly (hydroxy ethyl methacrylate) (PHEMA) and poly (titanium oxide) (-TiO₂-)_n obtained by sol-gel method in the presence of poly (oxypropylene glycol) (POPG) at various molar ratio of titanium isopropoxide (Ti(OPrⁱ)₄) to water. The samples of OI IPNs with different content of poly (titanium oxide) were synthesized. It was shown that the variation of the content of inorganic component affects their formation. The obtained OI IPNs were stated to be two-phase systems which consist of phases with almost pure components and the interfacial region (IFR). The mass fractions of polymers in the separated phases have been calculated using Fox equation. The part of the interfacial region in the studied samples (a relative value) has been calculated by Frid equation. When the molar ratio Ti(OPrⁱ)₄/H₂O at the formation of poly (titanium oxide) is equal to 1/1, the value of IFR increases with the growth of the quantity of inorganic component in OI IPNs, the forced compatibility of the system being retained.