The use of gel permeation chromatography in guiding polymer syntheses

Abstract

Abstract Gel permeation chromatography can contribute significantly to the guidance of polymer synthesis activities. Qualitative information about the effect of reaction variables on molecular weight distribution is satisfactory for such studies. Reaction mixtures can be analyzed without isolating the products of interest. Data are available soon after the reaction is completed, enabling future work to benefit from the information generated. The polymerization of propylene oxide in the presence of 1,5‐pentanediol and hydrocarbon solvent was shown to proceed in two steps. All the diol first reacted with propylene oxide to form an adduct at each hydroxyl function. Propagation with propylene oxide then proceeded with no further initiation and no termination reactions. Attempts to synthesize block copolymers in hydrocarbon solvent at 50°C. by the addition of a second monomer to polystyryl anions gave binodal molecular weight distributions. Polystyryl anions were shown to form species inactive toward further polymerization. Gel permeation chromatography also demonstrated the presence of a chemical composition heterogeneity in these products.