纤维素经铈离子引发丙烯酸接枝共聚机理研究

本文提出一种铈离子引发纤维素直接接枝丙烯酸的方法，该方法在完全水介质中进行且含均聚物最少。纤维素原料用硝酸铈铵（ＣＡＮ）引发预处理，加入计量的丙烯酸接枝共聚。利用正交分析讨论铈离子引发机理、影响预处理和接枝共聚的诸因素，纤维素接枝物用Ｘ－射线衍射和红外光谱进行表征。结果表明，用２０ｍｍｏｌ／ＬＣＡＮ在０．１４ｍｏｌ／Ｌ硝酸溶液中预处理２小时，在含６％（ｖ／ｖ）丙烯酸的０．２８ｍｏｌ／Ｌ硝酸溶液中接枝３．５小时，接技物的接技率可达１５７％。

MECHANISM OF GRAFTING COPOLYMERIZATION FOR ACRYLIC ACID ON CELLULOSE INITIATED BY CERIC ION

This paper proposes an initiation method using cerie ion to graft acrylic acid directly onto cellulose with the minimum amount of homo polymer in the aqueous medium. The eerie ammonium nitrate was used as an initiator for the pretreatment of cellulose and then a required amount of acrylic acid was added to the catalyst-treated cellulose for grafting copolymerization. With a cross-examination, the mechanism of initiation with ceric ion and the factors affecting the pretreatment and grafting reaction are discussed. The grafted cellulose was characterized by X-ray and IR spectrum. It was foundthat when the cellulose was pretreated with CAN/L 20 mmol in 0.14 mol/LHNO3 solution for 2h and then grafted in 0.28 mol/L HNO3 with 6%(v/v)acrylic acid for 3.5h, the graft yield of 157% was accessible.