Preflocculation of GCC with Cationic PAM and Cationic Starch and the Influence of Their Dosage and Shear Rate on Prefloc Size

양이온성 PAM과 양성전분에 의한 GCC의 선응집과 이들의 투입량과 전단속도가 선응집체의 크기에 미치는 영향

  • Lee, Kyong-Ho (Program in Environmental Materials Science, College of Agriculture and Life Sciences, Seoul National University) ;
  • Lee, Hak-Lae (Program in Environmental Materials Science, College of Agriculture and Life Sciences, Seoul National University)
  • 이경호 (서울대학교 농업생명과학대학 산림과학부 환경재료과학) ;
  • 이학래 (서울대학교 농업생명과학대학 산림과학부 환경재료과학)
  • Published : 2006.12.30

Abstract

Increasing the filler content of sheet provides an opportunity for saving production cost through fiber replacement with relatively low-priced filler. But increasing the filler content tends to decrease the strength of paper and filler retention. To overcome these problems, preflocculation technology of fillers has been suggested. To evaluate the effect cationic polymers on the size and size distribution of preflocculated GCC and their shear stability, cationic PAM and cationic starch were used. Results showed that cationic PAM formed large prefloc at low dosage. It was required to add 15 times as high as cationic starch to cationic PAM to obtain the same size prefloc. But preflocs formed with cationic starch was superior in shear stability to those formed with cationic PAM. With the increase of shear rate the size of preflocs decreased. Greater amount of small preflocs or un-flocculated fillers was observed when the dosage of polymers was low and this ended up low ash retention in handsheets.

Keywords

References

  1. Brown, A. J., 'Ground calcium carbonate fillers for high ash content, high strength papers', Proceeding of 1996 TAPPI papermakers conference, TAPPI PRESS, Atlanta, USA, p.137, (1996)
  2. Honig, D. S., Turnbull, R. J. and Wheeler, C., 'Retention system for highly filled paper', Proceeding of 1999 TAPPI papermakers conference, TAPPI PRESS, Atlanta, USA, p.1335, (1999)
  3. Mabee, S. and Harvey, R., Filler flocculation technology - increasing sheet filler content without loss in strength or runnability parameters', Proceeding of 2000 TAPPI papermakers conference, TAPPI PRESS, Atlanta, USA, p.797, (2000)
  4. Mabee, S. W., Controlled filler preflocculation - improved formation, strength and machine performance, Proceeding of 2001 TAPPI papermakers conference, TAPPI PRESS, Atlanta, USA, (2001)
  5. Gerischer, G., Murray, L. J. and Vanwyk, W. J., 'Improved retention of filler clay by means of pre-flocculation and selective dosing', Paperi Ja Puu,78(1-2): 51-56 (1996)
  6. Goto, S. and Pelton, R., 'The link between strength and shear sensitivity for filler flocs formed with retention aids', TAPPI J., 82(10): 1-9 (2000)