ABSTRACT
A series of tough polybenzoxazine-clay nanocomposites were prepared by novel method from organo-montmorillonite (OMMT) and bifunctional benzoxazine, bis-(3-dodecyel-3,4-dihydro-2H-1,3-benzoxazine) isopropane (B-dod). Benzoxazine monomer was in-situ formed in presence of organoclay. OMMT was prepared by modification of NaMMT with ammonium salts of amines such as tyramine (Tyr), aminolauric acid (ALA) and N,N-dimethylstearylamine. The thermal induced ring opening polymerization of hybrid materials was followed by DSC and IR. DSC indicted that, OMMT was effective to lower the temperature of ring opening polymerization of the monomers in comparison with the neat resin (B-dod). DSC confirmed that, the using of one shot process was more effect and processability than the traditional method (blend). The X-ray diffraction analysis indicated that organoclay was exfoliated into polybenzoxazine up to the higher content (20%). The hardness of the hybrid was evaluated, showing the effectiveness of the clay to give hard hybrid nanocomposites. The tensile properties of hybrid were examined, as the content of clay modified increase, the tensile modulus increase, however, the elongation at break decreased. Thermogravimetric analysis indicated that the nanocomposites have higher decomposition temperatures than that of the neat polybenzoxazine. Furthermore the char yield was shifted to the highest content because of the presence of clay loading.