Polyimide/Clay Nanocomposites Based on a New Aromatic Diamine (BAMO) Containing 1,3,4-oxadiazole Moieties

摘要

In current study, the synthesis of a new diamine 2,5-bis(3-amino-4-methyl benzene)-1,3,4-oxadiazole (BAMO) has been reported. Sodium montmorillonite (Na(+)Mt(-)) has been treated with hydrochloride salt of BAMO to give an organophilic clay BAMO-Mt. The clay treatment with BAMO increases basal spacing in the layered silicate showed by wide-angle X-ray diffraction (XRD). High thermal stability of BAMO-Mt in comparision with conventional montmorillonite modified with aliphatic long chain surfactants is found. A series of polyimide/organoclay nanocomposites (PCN) consisting of BAMO and benzophenone-3,3',4,4'-tetracarboxylic dianhydride (BTDA) were also obtained by an in with situ polymerization reaction followed by thermal imidization. Then, prepared nanocomposite materials were studied by XRD and transmission electron microscopy (TEM). Exfoliated PCNs were obtained for clay content of 1wt.%. PCNs with 3 and 5wt.% showed intercalation significantly. The obtained PCNs were studied by differential thermal analysis/thermogravimertic analysis (DTA-TGA) and dynamic mechanical thermal analysis (DMTA). Improved thermo-mechanical properties were observed for PCN 1wt.%.