alkenyl succinic anhydride size emulsions are prepared using a grafted cationic acrylamide starch co - polymer as an emulsification agent . the asa size emulsions of the present invention exhibit significantly greater stability compared to presently available asa size emulsions . the grafted starch co - polymer also is a more efficient emulsification agent for asa size , permitting the use of less emulsification agent , thereby saving cost .