不同电荷密度聚二甲基二烯丙基氯化铵固着剂的湿部化学行为

Wet End Performance of Polydiallyldimethylammonium Chloride Fixing Agents with Different Charge Densities

关键词:  聚二甲基二烯丙基氯化铵  固着剂  碱性过氧化氢漂白机械浆  溶解与胶体物质

Key Words:polydiallyldimethylammonium chloride  fixing agent  alkaline peroxide bleached mechanical pulp  dissolved and colloidal substances

摘要:选用4种分子质量相同而电荷密度不同的聚二甲基二烯丙基氯化铵（PDADMAC），考察了这4种PDADMAC作为固着剂控制碱性过氧化氢漂白机械浆(APMP)中溶解与胶体物质（DCS）时的湿部化学行为。结果表明，电荷密度越高的PDADMAC不仅更容易和浆料中的DCS作用，而且更容易被纤维吸附，同时其去除白水中的悬浮固体物质、DCS、以及COD的效果越好。

Abstract:Fixing agent is used to control the accumulation of dissolved and colloidal substances (DCS) in closed white water system, but how the charge density and molecular weight of a fixing agent affect its application efficiency is not clear in literature. As one of the two parallel studies, this study used four PDADMACs with same molecular weight but different charge densities as fixing agent to control the DCS in an alkaline peroxide bleached mechanical pulp (APMP). The results showed that PDADMAC with higher charge density is easier to interact with DCS, and also easier to be adsorbed onto the fibers so that the wet end performance will show greater change. Meanwhile, PDADMAC with higher charge density has better efficiency in removing suspended solid materials, dissolved and colloidal substances, and decreasing chemical oxygen demand.