Synthesis of polymaleamides by ring-opening polyaddition reaction of N,N′-disubstituted bisisomaleimides with diamines

The ring-opening polyaddition reaction of N,N′-disubstituted bisisomaleimides with various diamines in N-methyl-2-pyrrolidone at room temperature afforded polymaleamides having inherent viscosity up to 0.7 in almost quantitative yield. These polymers are a new class of homopolymaleamides and ordered alternating copolymaleamides. Almost all of the polyamides were soluble in a wide range of solvents such as dimethylsulfoxide, dimethylacetamide, m-cresol, and formic acid. They did not show any melt temperature, and began to decompose at a temperature ranging between 200 and 300°C.