中文摘要：

以双氰胺、甲醛为原料制备双氰胺甲醛（DDF）缩聚物，并研究DDF用作造纸助留助滤剂的可行性。探讨DDF用量、浆料pH值、混合时间及DDF与填料碳酸钙添加顺序4个因素对浆料助留助滤性能的影响，并通过扫描电子显微镜对DDF和阳离子聚丙烯酰胺（CPAM）在纸张中的留着情况进行了对比。实验结果表明，当先加入用量0．03％的DDF、再加入20％碳酸钙、浆料pH值9、混合时间6～7min时，浆料可获得较好的助留效果，但助滤效果不明显；扫描电子显微镜结果表明，碳酸钙和细小纤维在DDF作用下絮聚成体积较大的絮团，留着在纤维交织层中，从而提高了填料和细小纤维的留着率。

英文摘要：

In this paper, dicyanodiamide-formaldehyde （DDF） polycondensate was prepared using dicyanodiamide and formaldehyde as raw materials, and the feasibility of using DDF as a retention and drainage aid was studied. The effects of four influencing factors such as dosage of DDF, pH of pulp, mixing time and the adding order of DDF and CaCO3 on the retention and drainage performance were discussed, and its retention efficiency was compared with CPAM. The results indicated that DDF could obviously improve retention but not the case for drain- age. And retention reached the best in the conditions of DDF dosage of O. 03%, pH of pulp = 9 and mixing 6 ~ 7 min with adding DDF firstly.