Polyalkylene-imides (i.e., aliphatic-aromatic polyimides) were prepared smoothly in N-methyl pyrollidone from straight chain aliphatic diamines and pyrromellitic dianhydride. Melting points of the polymers ranged from about 300 to 450-degrees-C, depending of the length of the alkylene chains. An odd/even effect related to the alkylene chain was noted for melting points and glass transition temperatures (T(g)) of the polymers. The T(g)s were relatively high, especially when compared to similarly structured polyalkylene-heterocycles, e.g., polyakylenebenzoxazoles.