Study of sol–gel derived di-ureasils doped with zinc triflate

Zinc triflate (Zn(CF3SO3)2)-doped sol–gel derived di-urea cross-linked POE/siloxane ormolytes (designated as di-ureasils) with ∞>n⩾1∞>n⩾1 (where the salt content is expressed as n, the molar ratio of oxyethylene moieties to Zn2+ ions) were investigated. The hybrids with n⩾5n⩾5 are entirely amorphous; those with n>10n>10 are thermally stable up to approximately 305 °C. The siliceous network of representative samples (n=200n=200 and 10) is essentially composed of (SiO)3Si(CH2)-environments and is thus highly branched. The distance between the structural units in samples with 200⩾n⩾10200⩾n⩾10 and n⩽7n⩽7 is 4.2 and 4.3 Å, respectively. The estimated interdomain distance is 11 and 13 Å for xerogels with 200⩾n⩾20200⩾n⩾20 and n⩽10n⩽10, respectively. At n=1n=1 a crystalline POE/Zn(CF3SO3)2 complex of unknown stoichiometry is formed. The conductivity maxima are located at n=60n=60 (3×10−6 Scm−1) and n=20n=20 (7×10−5 Scm−1) at 30 and 100 °C, respectively.

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