The polyimide based on 3,3’,4,4’-benzophenonetetracarboxylic dianhydride and 1,4-diaminobutane (poly(BTDA-DAB)) does not crystallize from the melt. This paper describes attempts to enhance the crystallization of this polyimide. The spherulitic growth rate and the nucleation density of pure poly(BTDA-DAB) (<(M)over bar (W)>=35300) are quite low, namely G=0.031 mu m min(-1) and 1.7x10(7) cm(-3) respectively, both at 240 degrees C. Classical nucleating agents, such as talc and non-coated glass fibre, raise the nucleation density to 6-7x10(9) cm(-3) but endcapping the polyimide chains with -phi-SO3Na endgroups results in a nucleation density of 3.3x10(15) cm(-3). The highest crystallization rate is obtained for a sample in which 4.7% of the chains have been endcapped with -phi-SO3Na. Upon cooling from the melt at 20 degrees C min(-1), the heat of crystallization of this sample is ca. 32 Jg(-1), corresponding to a crystallinity of ca. 35%. Further, this paper demonstrates the synergistic effect of the simultaneous presence of -phi-SO3Na endgroups and 10 wt% of 4-hydroxybenzophenone as plasticizer. Further optimization is necessary to obtain a high molecular weight,semicrystalline poly(BTDA-DAB) upon injection moulding.