Methanol-Assisted ADMET Polymerization of Semiaromatic Amides

A method for the acyclic diene metathesis polymerization of semiaromatic amides is described. The procedure uses second-generation Grubbs' catalyst and N-cyclohexyl-2-pyrrolidone (CHP), a high boiling, polar solvent capable of solubilizing both monomer and polymer. The addition of methanol to the reaction was found to significantly increase polymer molar mass although the role of the alcohol is currently not understood. Hydrogenation with hydrogen gas and Wilkinson's catalyst resulted in near-quantitative saturation. All polymers synthesized here exhibit a hierarchical semicrystalline morphology driven by ordering of aromatic amide groups via strong nonbonded interactions. Furthermore, the melting points can be tuned over a >100 degrees C range by precise substitution at just one of the backbone positions on each mer (<5% of the total).

Automated summary

This paper describes a method for the acyclic diene metathesis polymerization of semiaromatic amides using second-generation Grubbs' catalyst and N-cyclohexyl-2-pyrrolidone (CHP), a high boiling polar solvent. The addition of methanol to the reaction increases polymer molar mass, although the role of the alcohol is not yet understood. Hydrogenation with hydrogen gas and Wilkinson's catalyst results in near-quantitative saturation. All polymers synthesized exhibit a hierarchical semicrystalline morphology driven by ordering of aromatic amide groups, and the melting points can be tuned over a >100 degrees C range by precise substitution at one backbone position on each mer (<5% of the total).