71-co-AN), such as the glass transition temperature, Tg; the sorption enthalpy, IH 1S, sorption free energy, IG 1S; sorption entropy, IS 1S; the weight fraction activity coefficients, a| 1a; partial molar free energy of mixing, IG 1a; partial molar heat of mixing
, IH 1a; and the Flory-Huggins interaction parameters, I 12a, at infinite dilution.
5 divided by R is equal to the heat of mixing, where R is the gas constant.
The heat of mixing is almost independent of the sample thickness.
DDB consists of five modules which may be purchased as a complete set or in part: The Vapor-Liquid-Equilibrium (VLE) Data Bank, The Heat of Mixing
Data Bank (HE), The Activity Coefficient at Infinite Dilution Data Bank (ACT), The Gas Solubility Data Bank (GLe), and The Excess Heat Capacity Data Bank (CPE).
Heat of mixing is introduced as a guide for phase stability predictions of polymer mixtures, and an appropriate equation is presented for it.
It must be noted that the noncombinatorial entropy contribution that has not been taken into account in Eq 1 can also affect the Gibbs free energy of mixing (9), but for polymer mixtures it has been demonstrated that the heat of mixing contribution often dominates the other contributions (10, 11).
Thus the temperature dependence of [varphi] is simply the sum of the molar heat of fusion of the additive and its partial molar heat of mixing with the polymer.
f], implying a negative heat of mixing, and the excess entropy of mixing is slightly negative.
The equilibrium-swelling ratio can be curve-fitted to a van't Hoff plot, and the heat of mixing [delta]H for different dosages are listed in Table 2.
The heat of mixing is almost independent of dosa ge in the range of [phi] [leq] 300 kGy, but becomes lower at [phi] = 400 kGy.
Another example where a negative heat of mixing between block and blend component has been found to result in a good compatibilizing effect is the emulsifying activity of poly(styrene-b-methyl methacrylate) in poly(vinylidene fluoride)/Noryl blends studied by Outhadi et al.
In the system PS/PMMA a negative heat of mixing is introduced between one of the graft copolymer constituents and one of the blend components.