抑制杨木APMP纸浆返黄技术的研究(Ⅰ)——助剂处理对黑杨APMP纸浆返黄的抑制作用

为减少APMP纸浆的返黄 ,该文主要研究了使用紫外光吸收剂、自由基清除剂等助剂处理黑杨APMP纸浆后 ,对其干 湿热和光返黄的抑制作用效果 .抗坏血酸可促进纸浆干 湿热返黄 ,在较大用量下 ,抗坏血酸及次亚磷酸钠对纸浆具有一定的光稳定作用 ;聚乙二醇对纸浆的光稳定效果较差 .对比研究几种紫外光吸收剂抑制纸浆光诱导返黄作用效果 ,ZW 1和ZW 2优于其它紫外光吸收剂 ,ZW 1在较低用量时对纸浆就有着较好的光稳定效果 ;较大用量下 ,ZW 2处理的纸浆抗长时间光老化能力略优于ZW 1.综合比较 ,所用助剂单独处理抑制黑杨APMP纸浆光诱导返黄能力大小排序为 :ZW 1>ZW 2 >抗坏血酸 >次亚磷酸钠 >ZW 3 >ZW 4>聚乙二醇

Techniques of yellowing inhibition for the Populus APMP(Ⅰ).Effectiveness of additives treatment

To diminish yellowing of the \%Populus nigra\% APMP,the effectiveness on brightness and brightness stabilization of \%Populus\% APMP pulp, by means of additives treatment, was investigated. Some kinds of additives, such as UV\|light absorbents and antioxidants,were applied individually to treat \%Populus\% APMP hand\|sheets.Light\|induced and heat\|induced yellowing behaviors of control samples and treated pulps were compared. It was showed that all of selected additives had lower effect on heat\|induced yellowing inhibition for \%Populus\% APMP. Comparison of ZW\|1 and ZW\|2 by the light\|induced\|yellowing inhibiting effect on the pulp illustrated that ZW\|1 had higher ability than ZW\|2 at lower dosage, while long time of light\|irradiation later, ZW\|2 does better than ZW\|1 at higher level of dosage. Ascorbic acid and sodium hypophosphite are able to partially prevent the pulp from light\|induced color\|reversion.