Chromatographic investigations of polyacetals in the critical range of liquid chromatography, 1. Analysis of 9‐anthrylmethyl‐terminated poly(1,3,6‐trioxacyclooctane)s

摘要

AbstractBifunctional poly(1,3,6‐trioxacyclooctane)s were obtained with (CF3SO2)2O as initiator in cationic ring‐opening polymerization via active chain‐end mechanism. To achieve a precise characterization of poly(1,3,6‐trioxacyclooctane) fractions with respect to molecular weight and end functionality, induced termination with ultraviolet (UV)‐active 9‐anthrylmethyl derivatives (ACH2—) was performed. This group improves the detection of the end‐functions and the separation into functionality fractions as it changes the hydrophilic‐hydrophobic balance of the macromolecules. With high‐performance liquid chromatography (HPLC) at the critical point of adsorption combined with photo‐diodearray detection and gel‐permeation chromatography (GPC) characterization of the molecular weight and the functionality distributions of the products was realized. Semipreparative separation followed by GPC and1H nuclear‐magnetic resonance (NMR) analysis of the fractions was used to determine their molecular weight distribution, average structure and type of the end groups. These analyses confirmed the correctness of the results from HPLC, based on elution at “critical conditions” of oligomers fitted with UV‐active groups. This method is suitable for the separation of poly(1,3,6‐trioxacyclooctane)s with