FUNCTIONALITY-TYPE DISTRIBUTION IN BRANCH ED POLYESTERS CONTAINING HYDROXY-GROUPS - CHROMATOGRAPHIC STUDY

Four types of branched polyesters based on adipic acid, diethylene gly col and trimethylolpropane, pentaerythritol, or glycerol, or on diethy lene glycol, dimethyl adipate, and trimethylolpropane were fractionate d with respect to functionality types (the number and type of end grou ps) using HPLC under the critical conditions (in the vicinity of the c oil-adsorbed coil transition). A serial Zorbax-Sil Golden column with ethyl acetate-tetrahydrofuran as a binary solvent was used. Under the critical conditions macromolecules are not fractionated with respect t o size, and the chromatorgams gave knowledge directly on the relative content of linear and branched functional molecules with different num bers of end groups. A universal chromatographic procedure for analyzin g the functionality-type distribution that is invariant with respect t o molecular mass distribution, was proposed.