漆酶对木素缩合结构的作用机制及高得率纸浆性能提升

The high content of lignin was kept in the high-yiled pulps, which influenced the pulp properties and applications.In this study, one of the key objective is to relveal the lignin structural change during laccase treatment and its mechanism, which will offer scietific and technical supprot to the quality improment for the high-yield pulps.. Lignin samples were isolated from fast-growing poplus and its high-yield mechanical pulps respectively. These lignin samples were treated with Lacse and Laccase-media-system (LMS) separately. The treated lignin samples were benzylated and the benzylated lignin samples were used to determing their lignin molecualr weight distributions through GPC technolgy. 31P-NMR and 13C-NMR spectra of these lignin samples were also obtained to analyze the condensed contents in lignin fractions.Through the changse of the contents of condensed lignin structures, the machnism of laccase treatment to lignin was studied..The high-yiled machenic pulps were treated with laccase and LMS respectively. The treated pulp samples were dissoved in an ionic liquid and analysis of molecular weight distributions and lignin strucural changes were able to be carried on. The condensed content in lignin samples were analyzed through 31P-NMR and 13C-NMR spectra. At the same time, the pulp physical and forming properties were analyzed to reveal the mechanism of laccase treatment to lignin condensed structures.

高得率纸浆中因木素含量较高而影响了纸浆的性能，本研究的主要目的是揭示漆酶等对高得率纸浆处理过程中木素缩合结构变化的规律及作用机制，为提高和改善高得率纸浆性能提供理论依据，提高高得率纸浆的品质。.从速生杨原料及其机械浆中分别提取木素，用漆酶和漆酶介体体系对这两种木素分别进行处理；处理后的木素样品，分别经过苄基化，然后通过凝胶渗透色谱分析其分子量分布的变化；通过31P-NMR和13C-NMR核磁共振波谱分析木素中缩合结构及含量的变化，揭示漆酶和漆酶介体体系对木素缩合结构的作用机制。.用漆酶和漆酶介体体系分别处理速生杨机械浆；以离子液体为溶剂，即将木粉和纸浆分别溶解在离子液体里，然后通过凝胶渗透色谱分别分析纸浆样品的分子量分布及其变化，通过核磁共振波谱分析木素中缩合结构含量的变化。并对纸浆的物理性质和成纸性能进行分析，揭示其影响规律。.在此基础上，选用复合酶处理纸浆，以达到提升纸浆品质的目的。

高得率纸浆中因木素含量较高而影响了纸浆的性能。本研究从速生杨原料及其APMP（碱性过氧化氢机械法）浆中分别提取木素，用漆酶和漆酶介体体系对这两种木素分别进行处理。处理后的木素样品，经过苄基化，采用凝胶渗透色谱法分析漆酶及漆酶/介体处理对木素分子质量的影响以及木素结构与分子量变化的关系；通过 31P-NMR和 13C-NMR 核磁共振波谱研究漆酶及漆酶/介体体系对木素中缩合结构及含量的变化，揭示漆酶和漆酶介体体系对木素缩合结构的作用机制。实验表明，漆酶和漆酶介体与木素的作用机理和反应过程有明显的差异。.本研究采用漆酶和漆酶介体体系对APMP纸浆进行酶法改性，研究了改性过程中各工艺参数的改变对纸浆的白度、抗张强度和撕裂度等物理性能的影响。实验发现，漆酶介体体系对纸浆中纤维长度，粗度以及纤维形态有重要影响。另外，漆酶及漆酶介体体系对抑制纸浆的返黄有明显作用。研究过程中还采用了热失重分析法检测了漆酶及漆酶/介体体系对木素分子热稳定的影响，以揭示漆酶及漆酶/介体体系对APMP纸浆热性能的作用机理。.用漆酶和漆酶介体体系分别处理速生杨机械浆；以离子液体为溶剂，即将木粉和纸浆分别溶解在离子液体里，然后通过凝胶渗透色谱分别分析纸浆样品的分子量分布及其变化，通过核磁共振波谱分析木素中缩合结构含量的变化，并对纸浆的物理性质和成纸性能进行分析，揭示漆酶和漆酶介体体系对其影响规律。.本研究为揭示漆酶等对高得率纸浆处理过程中木素缩合结构变化规律及作用机制提供了新的理论基础，为提高和改善高得率纸浆性能和品质提供了理论依据。