QUATERNARY AMMONIUM CATIONIC TARA GUM AND ITS APPLICATION FOR IMPROVING PERFORMANCE OF CHEMITHERMOLMECHANICAL PULP

In this study, tara gum (TG) was modified with an etherifying agent of 3-chloro-2-hydroxypropyl- trimethyl ammonium chloride (CHPTAC), and the product of quaternary ammonium cationic tara gum (CTG) was acquired. The effect of temperature, reaction time, dosages of etherifying agent, and NaOH charge on the degree of substitution of cationic tara gum was investigated. The charge density of the products was determined by a colloidal titration. The cationic tara gum was characterized by FT-IR and H-1-NMR, respectively. Furthermore, the effectiveness of cationic tara gum for improving the performance of chemithermomechanical pulp (CTMP) was examined. The optimized condition for preparing the quaternary ammonium CTG were basically as follows: temperature of 60 degrees C; reaction time of 3 hrs; m ((CHPTAC)) : m ((TG)) = 0.3 : 1; m ((NaOH)) : m ((TG)) = 0.3 : 1, respectively. Under this condition, the degree of substitution of acquired CTG reached to 32.7%. The surface charge density was increased with increasing the DS value. FT-IR and H-1 NMR analysis indicated that the cationic groups were connected to the molecules of TO With addition of modified tara gum, tensile and burst strengths of the handsheets can be significantly improved as applyed it to the CTMP. CTG showed a better reinforcing effect than the TO Compared with the untreated pulp, tensile index and burst index were increased by 29.3% and 27.4%, respectively, with adding 0.4% of CTG.