Calorimetric study of phase transitions for octylphenylthiolpentyloxybenzoate in silica aerogels
نویسندگان
چکیده
An a.c. calorimetric study has been carried out on octylphenylthiolpentyloxybenzoate (8ÂS5) in three silica aerogels with mass densities r=0 0́8, 0 1́7 and 0 3́6 g cm Õ 3 . Results for the least porous aerogel (r=0 3́6) are completely consistent with those reported previously for 8CB in the same aerogel. Freezing of 8ÂS5 damaged the more porous r=0 0́8 and 0 1́7 aerogels by creating internal voids and cracks that are large compared with the intrinsic pore size. As a result, overlapping sharp bulk-like Cp features and rounded features due to 8ÂS5 in residual aerogel pores were observed, and no quantitative separation of these features could be achieved.
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