Journal of Physical Chemistry, Vol.98, No.34, 8580-8584, 1994
Polymer Swelling .16. Sorption of Linear Aliphatic Ethers by Poly(Styrene-Co-Divinylbenzene)
The adsorption parameters, alpha(m,n,) for linear aliphatic ethers of the types H(CH2)(m)O(CH2)(m)H, with m = 2-7, and H(CH2)(m)O(CH2)(n)H, with m = 1 or 2 and n = m to 8, were established in the usual way, using microporous composite film samples comprising (Sty)(1-x)(DVB)(x) particles enmeshed in poly(tetrafluoroethylene) microfibers. The set of log alpha(m,n) values obtained thereby were correlated with the values of m + n to create a grid pattern that resembled in form the grid patterns reported for a homologous series of the types ZCH(3-m)(CH3)(m), and Z(CH2)(n)H, where Z represents a phenyl group or halogen atom. The apparent precision of the grid pattern established here for aliphatic ethers enabled the alpha(m,n) values to be predicted for ethers not yet determined experimentally. Subsequently, when five of these became available for testing, the results obtained were within +/-0.01 of the predicted values. Each insertion of a CH2 group into the shorter chain (m) causes about 3 times as great an effect on alpha(m,n) as it does when on the longer chain (n). This suggests that both the ether oxygen atom and the shorter chain (m) attached thereto are in intimate contact with the adsorption site, i.e., the phenyl group of the polymer, whereas the longer chain (n) extends above that site in dynamic association with the sorbed-but-not-adsorbed molecules in the liquid-saturated gel, as noted in the earlier studies of sorption of ZR liquids by (Sty)(1-x)(DVB)(x) particles.
Keywords:SYSTEMS