Electrospinning technique was employed to obtain uhrafine fibers of poly (carbon dioxide-co-propylene oxide)．The effects of electrical potential

distance from spinning tip to collector

solution concentration and solvent system on the fiber morphology

fiber diameter and dispersion coefficient were discussed．Morphology and dispensability of electrospun nonwoven mats were determined by scanning electron microscopy (SEM)．The results show that fibers of poly(carbon dioxide-co-propylene oxide) with a diameter range from less than 200 nm to 7 μm can be obtained via electrospinning process．It was also found that the electrical potential and solution concentration were strongly correlated with the formation of bead defects in electrospun fibers．Bead defects oecured at low electrical potential and concentration and the form of the beads changed from sphere to spindle

when the electrical potential or solution concentration increased．Electrical potential

spinning distance and solution concentration were all foand to have great influence on the fiber diameter and dispersion coefficient．Below a certain value of electrical potential the average diameter of electrospun fibers increased and the dispersion coefficient decreased with increasing the electrical potential．However

when electrical potential at the spinning tip reached a relatively high value

the trend went opposite due to great instability caused by the high electrical force．With the increase of distance between spinning tip and conector

the average diameter of electmspan fibers declined

while the dispersion coefficient increased．When the solution concentration increased

the average diameter increased

while the dispersion coefficient declined．The results also illustrated that the solvent system may greatly affect the morphology of eleetrospun fibers．In the CH2Cl2 and butanone salvent system a bimodal distribution of fiber diameters was observed due to jet splitting．