聚丙烯酰胺对TiO2复合纸板助留效果的影响

由于TiO2粉体颗粒细小、易团聚、难回收,限制了其在降解水中污染物方面的应用。纸板作为一种负载TiO2的新方法能有效解决上述难题,提高TiO2粉体在纸浆纤维上的留着率,对负载TiO2复合降解纸板效能的发挥有重要意义。通过对含TiO2模拟纸浆液浊度变化的分析,探讨了不同类型聚丙烯酰胺(PAM)以及聚二甲基二烯丙基氯化铵/阳离子聚丙烯酰胺(PD/APAM)不同配方对TiO2粉末在纸浆纤维上的留着影响; 再通过抄片实验研究了二元PD/APAM助留体系对负载TiO2粉末复合降解纸板中纸浆纤维留着率、TiO2留着率和环压强度指数的影响。结果表明:助留剂的离子形态对纸料留着率有显著影响,阳离子型PAM助留剂能显著降低悬浊液的浊度; PD/APAM二元助留体系降浊效果更显著。总添加量为2.0%的PD/APAM二元助留体系在负载TiO2粉末复合降解纸板中,可将TiO2粉末的留着率从51.9%提高到88.9%,纸浆纤维的留着率从65.7%提高到92.1%,同时纸板的环压强度指数从1.24 Nm/g提高到4.62 Nm/g。
The TiO2 particles are easy to agglomerate and difficult to be separated, which prevents their application to waterborne pollutants treatment.Paperboard has been applied as a suitable supporting matrix to load TiO2 particles, and improving the retention ratio of TiO2 particles on the pulp fiber is important for the composite paperboard bearing TiO2 particles.In this study, the changes of the turbidity of the TiO2-containing simulated pulp solution were measured; the effects of different types of polyacrylamide(PAM)and poly dimethyl diallyl ammonium chloride(PD)/anion PAM(APAM)on the turbidity of the pulp solution were investigated, the retention ratios of fibers, the retention ratios of TiO2 and the ring crush strength of the composite paperboard were investigated.The results showed that the ion state of the retention agent had a significant influence on the retention of TiO2 particles on the paper fibers.The cationic PAM retention agent could significantly reduce the turbidity of the suspension, while the PD/PAM retention system could reduce the turbidity more significantly.The PD/APAM binary retention system also improved the ring crush strength of the paperboard.With the 2.0% mass ratio addition of PD/PAM based on the mass of pulp suspension, the retention ratio of TiO2 powder significantly increased from 51.9% to 88.9%, while that of the pulp fibers increased from 65.7% to 92.1%, and the ring crush strength increased from 1.24 Nm/g to 4.62 Nm/g