Calculate the entropy of a mixture of toluene and PMMA, considering that PMMA has a MM = 235,000( g)/(m)ol, 100 g of each component are mixed, and the density of the polymer is considered to be 1.0( g)/(c)m3
and that of toluene 1.92( g)/(c)m3.
Consider that the polymer consists of i segments, each of which can displace a single solvent molecule from a lattice site and therefore:
i=(M_(2))/(\rho _(2)V_(1))where M2 is the molecular weight of the polymer that would have a density \rho 2 in the amorphous state corresponding to the solution temperature and V1 is the molar volume of the solvent.
\phi _(1)=(n1*V1)/(n1V1+n2V2)=(n1)/(n1+in2) and \phi _(2)=1-\phi _(1)