Excess molar volumes for binary mixtures of 1-alkanol and 1-alkene.: II.: The system 1-alkanol+1-octene at 15 and 35°C

Excess molar volumes V-E measured at 15 and 35degreesC for the (1-propanol + 1-octene), (1-butanol + 1-octene), (1-octanol + 1-octene), and (1-decanol + 1-decene) systems are reported. These data and the measurements reported before at 25degreesC for this series of mixtures were used to calculate the excess molar isobaric thermal expansion A(p)(E) = (partial derivativeV(E)/partial derivativeT) p at 25degreesC. In the above series of mixtures the A(p)(E) values change from positive over the whole concentration range in the systems formed by 1-propanol and 1-butanol, to positive-negative for longer chain alkanols, the positive values occurring in the alkene-rich region. For systems characterized by the sigmoid shape, the positive region of A(p)(E) values decreases with increasing length of the 1-alkanol molecule. The modified model of associated mixtures proposed by Treszczanowicz and Benson predicts qualitatively the changes in the shape of the A(p)(E) curves. The model allows interpretation of the above results as a balance between the contributions due to self-association of alkanol, nonspecific interactions, and free volume.