导　　师： 王双飞

学科专业： H2201

授予学位： 硕士

作　　者： ;

机构地区： 广西大学

摘　　要： 本论文对粉单竹apmp法制浆和补充漂白过程中的制浆机理和漂白机理进行了比较系统的研究，并初步探讨了漂白apmp竹浆的返黄性能和机理。 首先，对粉单竹apmp法制浆和补充漂白前后，竹材的化学组分和纤维形态的变化进行了研究。实验结果表明，竹材原料化学组分中抽出物含量比较高，如苯醇抽出物3.19％，1％naoh抽出物29.85'x,经过apmp法制浆和过氧化氢补充漂白后，苯醇抽出物大量溶出，溶出率高达84.32％，苯醇抽出物中含有大量有色物质，其溶出有利于提高成浆的白度；1％naoh抽出物的溶出也较高，溶出率高达54.4％，同时也降低了制浆得率。扫描电镜(sem)观察表明，经过apmp法制浆后，竹材纤维已经充分分离，并且纤维间夹杂着大量的碎片，碎片的主要成分应该是剥落的纤维细胞角隅和复合胞间层，经过补充漂白后这些剥落的碎片明显减少，纸浆的白度得到提升，同时纤维表面也受到一定程度的润胀，柔软性增加，使成纸纤维交织得更加紧密。 其次，运用红外光谱、凝胶色谱、h-nmr等现代分析手段，对apmp法制浆和h<,2>o<,2>补充漂白过程中，竹材mwl的结构变化进行研究。结果表明，竹材木素属于gsh型木素，并且含有大量的缩合g型木素单元，另外竹材木素中存在较多的酯键连接。凝胶色谱分析表明，经过apmp法制浆后，竹材木素大分子结构被碎解，磨木木素分子量减小，多分散性增加；红外光谱和<'1>h-nmr谱分析表明，木素的g型和h型结构单元较易于溶出，s型和缩合g型单元得到保留；发色基团含量测定表明，制浆过程中，虽然竹材木素中共轭羰基含量有所上升，但总的含量比较低，而醌型结构含量非常高，是竹材及竹浆颜色的主要来源。 最后，论文研究了漂白apmp竹浆的返黄性能，并探讨了其返黄机理。研究表明，漂白apmp竹浆易于光返黄，在紫外光照射6小时后，白度损失达16.67％，而且不同光照射时间内，返黄速率不同，说明了竹浆光返黄机理的多重性。对光返黄机理进一步研究表明，漂白竹浆中的残余木素在遭受紫外光照射后会发生一定程度的降解，木素分子量降低，并且从木素大分子上脱离大量易溶出的含有发色结构的苯环低聚物，这些苯环低聚物以h型单元为主。 In the thesis, the mechanism of pulping and bleaching of APMP of Bambusa Chungii was researched. And then we studied the properties and mechanism of light-induced yellowing of bleached APMP bamboo pulp. Firstly, we studied the changes of chemical ingredients and fiber morphology of Bambusa Chungii during APMP pulping and supplementary bleaching. The results showed that there is a high content of extractions in bamboo chemical components. For example, the alcohol-benzene extractive content is 3.19/%, and l/%NaOH extractive content is 29.85/%. Most extractions in initial bamboo material were dissolved away during the APMP pulping and supplementary bleaching, and it was of great benefit to pulp brightness but a disadvantage for the yield of pulp. The SEM observation revealed that the bamboo fibers were divided completely and a large amount of fragments stuffed around fibers. We promoted the pulp brightness while these fragments which must be middle lamella remainders were removed from pulp by supplementary bleaching. Meanwhile, fiber surface properties were also improved. Secondly, the modern spectrum analytical technologies were applied to study the changes of lignin structure of Bambusa Chungii during pulping and bleaching. The results indicated that the lignin of Bambusa Chungii is a GSH style lignin with a large amount of condensed G style. There were also many ester bond linkages in bamboo Ugnin. By measuring the molecular weight distribution, it was found that after APMP pulping the macromolecule structure of bamboo lignin was broken down, and the average molecular weight of lignin decreased, also the polydispersity of it increased. FTIR and H-NMR analysis

关 键 词： 粉单竹 浆 漂白 木素结构 光返黄

分 类 号： [TS749.3]

领　　域： [轻工技术与工程]