填料包覆预絮聚改性技术及其对纸张性能的影响

Filler Modified by Encapsulation-preflocculation Method and Its Effect on Paper Properties

关键词:  碳酸钙  阴离子聚丙烯酰胺  阳离子淀粉  阳离子聚丙烯酰胺  聚合电解质复合物

Key Words:calcium carbonate  anionic polyacrylamide  cationic starch  cationic polyacrylamide  polyelectrolyte complex

摘要:采用阴离子聚丙烯酰胺（APAM）、阳离子淀粉（CSt）和阳离子聚丙烯酰胺（CPAM）对碳酸钙（CaCO₃）填料进行包覆预絮聚改性，制备包覆预絮聚改性填料（CaCO₃-APAM-CSt-CPAM），并将其与仅采用絮凝剂改性的预絮聚改性填料（CaCO₃-CPAM）相比较。结果表明，相比单一的预絮聚改性技术，包覆预絮聚改性技术能显著增大填料粒径并提高填料表面正电势，从而更有效地提高填料留着；当纸张灰分含量为21%时，包覆预絮聚改性填料在提高成纸抗张强度、内结合强度和撕裂度方面比预絮聚改性填料更具有优势，包覆预絮聚填料加填纸的抗张指数和内结合强度是未改性填料加填纸的1.88倍和1.50倍，是预絮聚改性填料的1.14和1.15倍，且能更好地维持纸张的匀度。

Abstract:Filler modification by encapsulation-preflocculation was carried out by sequentially adding anionic polyacrylamide， cationic starch and cationic polyacrylamide， which formed mulitiple polyelectrolyte complexes.The modified filler was used for papermaking and compared with the filler modified only by preflocculation.The results showed that compared to the single preflocculation treatment， the encapsulation-preflocculation treatment resulted in significantly larger particle size and higher surface charge potential of the fillers which led to higher filler retention.At the same level of paper ash content， the encapsulation-preflocculation modified filler had more advantage in improving the paper tensile index， internal bonding strength and tearing index than the preflocculated filler， and its application also led to the better paper formation．