of course  Dr. S. Kalidhasan  is right morphology strongly depend on temperature, pressure, PH , and time, also varies for different substances. please refer this article Papa, Anne-Laure, et al. "Effect of reaction parameters on composition and morphology of titanate nanomaterials." The Journal of Physical Chemistry C 113.29 (2009): 12682-12689.

I think incomplete washing cannot affect the final PANi nanostructure.

definitely not the incomplete washing affect the material morphological, temperature, precursor concentration and other parameters may play important role. 

good thing is that you already got the tubular structure, next step is the optimization. good luck.

I think it can influence the morphology. At least, I found vigorous sonication can even break nanotubes.