Polyacrylamide (PAAm) with ultrahigh molecular weight of 9 x 10(6) g/Mol has been processed by means of electrospinning, to afford products with a variety of morphologies, including polymer colloids, beaded fibers, smooth fibers, and ribbons. These morphologies can be controlled by a minute change of solution concentration in a small concentration range (0.3-3.0 wt %), because of the high molecular weight of the polymer. Under our experimental conditions, no electrospun product was obtained at the concentrations below 0.3 wt %. Beaded fibers and smooth fibers formed at the concentrations between 0.3 and 0.7 wt %. At concentrations between 0.7 and 2.0 wt %, smooth fibers and ribbons coexisted. At concentrations above 2.0 wt %, ribbons were the only product. Special morphologies such as triangular beads, helical fibers, and zigzag ribbons were also observed. With a lower molecular weight PAAm, branched fibers were found in the product. (c) 2005 Wiley Periodicals, Inc.