AbstractMichael additions of the secondary diaminesN,N′‐dimethyl‐1,6‐hexanediamine (14) or piperazine to the electrophilic carbon–carbon double bonds ofN,N′‐bismaleimido‐4,4′‐diphenylmethane (2) orN,N′‐bismaleimido‐1,8‐octane (4) afford four unusual, high‐molecular‐weight (ηinh= 0.49–2.16 dL/g) polyimides (10–13). The most interesting of these, polymer12(the product of4and14), is a tough elastomeric resin with a glass transition temperature (Tg) near 0°C; in contrast,10, 11,and13exhibitTg>86°C. Freshly prepared12is soluble and thermoplastic (12is readily compression molded at 110°C), but the bulk polymer crosslinks slowly under ambient laboratory conditions and eventually (48 days) becomes insoluble, while10, 11,and13remain soluble indefinitely. Along with further comparisons of the properties of10–13, details of the synthesis and characterization of these new polyimides are described. Also discussed are reactions of bismaleimide2with 1,6‐diaminohexane, which unlike the formation of linear10
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