Polyacrylamide stabilized alkenyl succinic anhydride emulsion as sizing agent for various cellulosic pulps and fillers

Abstract

Cellulosic fiber is hydrophilic in nature and making it hydrophobic represents a process called sizing in papermaking. Alkenyl succinic anhydride (ASA) sizing is dominating over other sizing processes due to its high reactivity and economy. The shelf life of conventionally used cationic starch (CS) stabilized ASA emulsion is 20−25 min. In our previous study, the ASA emulsion was found to be stable up to 4 h using anionic polyacrylamide (APAM) as stabilizer. Present communication was aimed to utilize, the APAM stabilized ASA emulsion with most commonly utilized cellulosic pulps (mixed hardwood, bagasse and recycled) and fillers to assist its commercial utilization in papermaking. APAM stabilized ASA emulsion facilitated back water utilization with improved sizing degree unlike CS based ASA emulsion. Lower amount of ASA sizing was required in bagasse pulp compared to other pulps which might be attributed to low crystallinity ratios and hydrogen bond energy.