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竹子作为一种重要的非木材制浆造纸资源,具有生长周期短、储量大及成本低等优点,但是其成浆存在白度低、白度稳定性差、易返黄、废液硅含量高难处理等问题.本研究利用H2O2、NaBH4、Na2S2O4和CH3COOOH等漂白剂对粉单竹碱性过氧化氢化学机械浆(APMP)进行单段或者两段组合补充漂白,以提高竹子APMP浆的可漂性、白度及其稳定性、强度等.研究结果表明,常规H2O2漂白是竹子化机浆最佳单段补充漂白方法.两段补充漂白实验表明,白度提高最大的是H2O2→Na2S2O4组合,为73.85％ISO;黏度下降最大的是H2O2→NaBH4组合,漂后浆黏度从960下降到601 mL·g-1.虽然两段补充漂白漂后浆的黏度有所下降,但其物理强度得到提高.补充漂白的示差红外分析发现:H2O2、H2O2→Na2S2O4、H2O2→NaBH43种漂白方法的纸浆中共轭羰基含量降低了,而H2O2→CH3COOOH漂白浆中的共轭羰基含量反而增加.甲氧基、紫丁香型木素和缩合的愈创木基环在H2O2→Na2S2O4两段补充漂白过程脱除效果最显著.X射线衍射分析表明,补充漂白过程单段H2O2和H2O2→Na2S2O4两段漂白对碳水化合物的降解作用最小.“,”The bamboo can be a kind of important non-wood pulp used as paper resources,which has a short growth period,and is in a large reserve and with a low cost.But the bamboo pulp faces some problems,such as the low whiteness and the poor stability of the whiteness,the high yellow index,and it is difficult to deal with due to its high silicon content.In order to improve the bleachability,the whiteness and its stability and strength of the bambusa chungii APMP pulp,the hydrogen peroxide,the sodium borohydride,the sodium hydrosulfite,the peracetic acid and the oxygen are used as the bleaching agents in single stage or two stage combination supplementary bleaching.The results show that the best single stage supplementary bleaching of the bamboo chemi-mechanical pulp is the conventional hydrogen peroxide bleaching.Two supplementary bleaching experiments show that the greatest improvement of the whiteness is made by the combination of the hydrogen peroxide and the sodium hydrosulfite,with the whiteness being 73.85％ ISO;the largest reduction of the viscosity is made by the combination of the hydrogen peroxide and the sodium borohydride,with the viscosity reduced from 960 mL· g-1 to 601 mL· g-1.Although the pulp viscosity is reduced after two supplementary bleachings,the physical strength is improved.The conjugated carbonyl content in the pulp is decreased with the use of the hydrogen peroxide,the combination of the hydrogen peroxide and the sodium hydrosulfite and the combination of the hydrogen peroxide and the sodium borohydride,but the content is increased with the use of the combination of the hydrogen peroxide and the peracetic acid.The most significant removal effect of methoxy,lilac lignin and condensation guaiacyl ring is produced by the combination of the hydrogen peroxide and the sodium hydrosulfite in the supplementary bleaching.The minimum degradation of the carbohydrates is produced by the hydrogen peroxide and the combination of the hydrogen peroxide and the sodium hydrosulfite in the supplementary bleaching.