Thermomechanical characterization of thermoplastic polyimides containing 4,4'‐methylenebis(2,6‐dimethylaniline) and polyetherdiamines

In this work, we synthesized polyimides by incorporating an aromatic diamine monomer with a methylene linker, 4,4'‐methylenebis(2,6‐dimethylaniline) (MBDMA), to make a robust main chain along with aliphatic polyetherdiamine backbone linkers to reduce rigidity. We designed the polymers to exhibit thermal properties in between those of conventional aromatic polyimides and polymers with wholly aliphatic ether diamine links. Through dynamic mechanical analysis and differential scanning calorimetry, it is shown that control of the molar ratios of the aromatic MBDMA (4,4'‐methylenebis(2,6‐dimethylaniline)) and the composition and size of the aliphatic polyetherdiamine can be used to tune the glass transition. The polymers were characterized by GPC, FTIR, NMR, thermomechanical and calorimetric analysis, and microhardness testing. POLYM. ENG. SCI., 59:221–232, 2019. © 2018 Society of Plastics Engineers