Adsorption of polyesters on glass, silica, and alumina

The adsorption of se veral saturated , linea r polyesters has been studied under a varicty of conditions. The study also included di-n-butyl sebacate as a model low molecul ar weight ester and poly (met hyl m ethacrylate). The adsorbents were type E glass powder, silica, a nd a lumina. The glass powder and silica were nonporous materi als; t he alumina contained a lal'ge internal pore structure. The rate of adsorption of t he polyesters on glass was very ra pid and t he adsorpt on isotherm was irrevcrsible. Adsorption from a poor solven t was favored over adsorpt ion from a good solvent. A large number of sitcs a re available on t he adsorbent for bond format ion and the adsorbed polymer m ost proba bly extends into t he solution in a coiled configuration. Metallic ions, in a ddition to silicon , a ppear to be involved in a n electrostatic bond between t he polymer and t he glass. The Langmuir eq uation is obeyed at high-equilibrium co ncentrat ions, although t hcre is nonconformity at t he low concen trations. I P resented before t h e Di v ision of Polymer Chemistry of the American Chemical Society at t he Snn FranciSCO m eeting, April 1958. , This work was done, in p art, under a project sponsored b y the Bureau of AeronautiCS, D ep. rlm ent of the N ay )".