中文摘要：

目的利用2,2,6,6-四甲基哌啶氧化物自由基（TEMPO）/NaClO/NaBr氧化体系改善废纸浆纤维成纸的性能。方法以废纸浆为原料,在碱性条件下采用TEMPO/NaClO/NaBr氧化体系对纤维进行选择性氧化,得到不同羧基含量的氧化废纸浆,通过纤维形态分析仪及化学分析法对纤维形态和羧基含量进行分析和测定;将氧化废纸浆、氧化废纸浆与原浆进行抄片和配抄,对手抄片的强度性能进行检测和分析;从经济效益出发,研究氧化体系中TEMPO及NaBr的循环使用次数对纸张强度性能的影响。结果随着NaClO用量的增加,废纸浆纤维的羧基含量增加;纤维长度、宽度和粗度有所降低;纸张抗张强度和环压强度增长较为明显;NaClO和NaBr循环使用2次后纸张的强度性能有所降低,但降低幅度不大。结论TEMPO氧化体系可用于废纸浆的氧化,改善废纸浆的性能。NaClO和NaBr的循环使用能够降低生产成本。

英文摘要：

The work aims to improve the waste paper fiber performance by 2, 2, 6, 6-tetramethylpipelidine-1-oxylradical（TEMPO） /NaClO/Na Br mediated oxidation system. Waste paper pulp was selectively oxidized with 2, 2, 6, 6-tetramethylpipelidine-1-oxylradical TEMPO/NaClO/Na Br mediated oxidation system under alkaline conditions. Pulp with various amount of carboxylate groups was obtained. Fiber morphology analyzer and chemical analysis were applied to observe the fiber shape and analyze amount of carboxylate groups, respectively. Then, handsheets were prepared from oxidized pulp and unoxidized pulp. The effects of carboxylate content of oxidized pulp, the amount of oxidized pulp added and NaClO/Na Br reusable times for paper strength properties were discussed. Carboxylate groups content of waste paper pulp increased with the increase of NaClO dosage. Fiber length, width and coarseness reduced somewhat. Tensile strength and ring crush strength of paper prepared from oxidized waste paper pulp increased obviously. Paper strength decreased a little after TEMPO and Na Br recycled twice. In conclusion, TEMPO oxidation system can be used for waste paper pulp oxidation to improve the waste paper fiber performance. The cost of production can be reduced by a way of recycling NaClO and Na Br.