STUDY OF MOLECULAR MOTIONS IN EPOXY NETWORKS USING SOLID STATE DEUTERIUM NMR

摘要

Glassy polymer networks used in composite matrices dissipate energy at the molecular level through bond rotations, torsions, and ring flips. Analytical techniques to study molecular motions using solid state deuterium NMR have been developed in our labs. We have synthesized deuterated (D-8) diglycidyl ether of bisphenol A (DGEBA) and crosslinked this monomer with 4,4'-diaminodiphenyl sulfone (4,4'-DDS) and 3,3'-diaminodiphenyl sulfone (3,3'-DDS) to study the influence of amine isomer position on molecular motions using solid state NMR. Specific molecular motions associated with amine isomer position have been identified to correlate network architecture and molecular mobility. These results provide insights that link molecular architecture with observed differences in thermomechanical properties of 3,3- vs. 4,4-DDS epoxy polymer systems.