漆酶和漆酶／介体处理提高未漂化学木浆湿强度的研究

研究了漆酶和漆酶/介体体系处理对未漂硫酸盐浆强度和白度的影响。结果表明,与空白样相比,漆酶处理可显著改善纸浆的湿抗张强度,但对干抗张强度和撕裂强度无明显影响,且纸浆白度有所降低。丁香酸甲酯(MS)是一种高效的介体,介体本身对纸张的强度和白度无影响,但与漆酶协同作用可使纸浆的湿抗张强度提高1倍以上。漆酶最佳用量为16U/g绝干浆;丁香酸甲酯的最佳用量为0.5%。高温干燥有助于提高纸张的再湿强度,在单独使用漆酶处理时更为重要。在单独漆酶处理过程中,通氧与通空气对提高湿抗张强度的效果无明显区别;而漆酶/介体体系处理中,通氧气可获得比通空气更高的湿强度指标。

Enhancement of Wet-strength of Unbleached Pulp with Laccase and Laccase-mediator Treatment

The influence of laccase and laccase-mediator system treatment on tensile strength, wet strength in particular, and brightness of unbleached kraft pulp was studied in this paper. It was found that treatment with laccase alone could enhance the wet-tensile strength and had little effect on the dry-tensile strength and dry-tear strength of the handsheet. A decrease in brightness was observed after laccase treatment. It was found that methyl syringate (MS) was an efficient mediator among various mediators studied. MS itself had no effect on the strength properties and brightness. However, a onefold increase in wet-strength and lower brightness could be obtained through laccase/MS treatment compared with the untreated sample. The optimal dosages of laccase and MS were 16 IU/g pulp and 0.5% based on dry pulp, respectively. In addition, heat-dry of handsheet contributed to a higher dry-strength, especially played a significant role in wet-strength improvement in lacase alone treatment system. During laccase alone treatment process, there was little difference in wet-strength between applying oxygen and using air. In laccase-mediator treatment system, applying oxygen could lead to a slightly higher wet-strength of handsheet than applying air.