Sizing performance and molecular orientation of dispersed cationic rosin-ester

摘要

The role of alum in dispersed cationic rosin-ester sizing was investigated in terms of rosin-ester molecular orientation by using X-ray diffraction, contact angle and conventional sizing measurement. The results showed that alum hindered both hydrophilic and hydrophobic re-orientation of rosin-ester molecules by increasing intermolecular attractions. The hydrophobic effect of dispersed rosin-ester size might be developed via preventing its molecules from hydrophilic orientation induced by water during the drying process. Benzene induced the hydrophobic re-orientation of rosin-ester. The hydrophobic re-orientation of rosin-ester molecules enhanced sizing, whereas the hydrophilic re-orientation lowered sizing. The increased rosin intermolecular attraction induced by alum may hinder both types of re-orientation.