Synthesis and Characterization of New Functional Bismaleimides

Functional bismaleimides containing γ-lactone, carboxyl, aldehyde, hydroxyl, azomethine or cinnamoyl groups were synthesized from maleimido benzoic acid via its acid chloride with phenolphtaleine, 5,5′-methylene-bissalicylic acid, 5,5′-methylene-bissalicylaldehyde, glycerol, tartaric acid and 3,4-bis(hydroxyethan-2-tioether)- p-maleimidobenzoic acid, by simple condensation or polymer analogous reactions on some of these reactive bisimides.

The monomers were characterized by IR, 1H-NMR and elemental analysis. The DSC curves of all the samples showed an exotherm in the temperature range of 134–310 °C, which is attributable to curing reactions. Thermogravimetric analysis of the uncured resins indicated good thermal stability and a char yield of bismaleimide resins in accordance with the calculated C/H ratio. Their relative thermoxidative stability was evaluated by isothermal gravimetric analysis.

The synthesis, characterization and polymerization kinetic study of a series of related addition polyimides

A series of eight addition polymides (aspartimides) was prepared in which the imide and amino groups were attached to the ends of aromatic residues containing two or four phenylene rings. The co-monomers (bis-maleimides. BMIs, and diamines) were purified using column chromatography before being fully characterized by spectroscopic techniques. The thermally induced Michael addition and polymerization reactions of the blended co-monomers were monitored using differential scanning calorimetry (Dsc) at several heating rates to enable the kinetics of the processes to be investigated. The thermal stabilities of the thermoset products of these aspartimides were evaluated by thermogravimetric analysis (TGA). Dynamic mechanical thermal analysis (DMTA) was employed to test the physical properties of the neat resins.