Sizing Mechanism of Emulsion Rosin-Aluminium lon Systems

本研究的目的是阐明造纸过程中内部施胶处理的两种机理;研究了阴离子乳液-松香胶/硫酸铝体系在湿部的助留机理和浆料组分在纸页中的施胶机理，得到了以下结果：1.建立了测定板材中少量浆料和铝组分的方法，气相色谱法和其他分析仪器。使用上述纸张方法发现，加入到纸原料中的铝离子立即与纸浆纤维中的解离羧基形成离子键。因此，在纸浆COOAI处形成的纸浆表面的阳离子位点可以通过阴离子相互作用吸附阴离子松香乳液。当纸浆的pH值通过添加碱性溶液而增加时，离子键，纸浆-COO-Al-松香乳液，由于松香乳液的分解和其他原因而断裂。因此，乳液松香胶/铝离子体系在湿部的助留机理是在纸浆纤维的羧基上直接形成离子键。其次，通过研究浆料组分在纸页中的化学结构和性能，阐明了乳液松香胶/铝离子体系的施胶机理。使用以下分析技术：1）分析纸张的纤维素酶处理的残留物，2）用有机溶剂提取纸张，和3）用13 C-标记的脂肪酸作为松香胶的模型化合物制备的纸张的固态13 C-NMR分析。结果表明，松香分子以游离酸的形式存在于纸页中，不形成铝盐。此外，保留在纸页中的铝离子决定了疏水性松香胶组分在纸浆纤维表面的分布模式或映射结构。

The goal of this research was to clarify two mechanisms of internal sizing treatments in paper-making process ; retention mechanism of the anionic emulsion-rosin size/aluminium sulfate system in wet-end and its sizing mechanism of size components retained in sheet, and the following results were obtained.First, the methods for determining small amounts of size and aluminium components in sheets were established uisng pyrolysis-gas chromatography and other analytical apparatus. it was found using the above methods of paper-sheets that aluminium ions added to paper stodck immediately formed ionic linkages with dissociated carboxyl groups in pulp fibers. Thus, the cationic sites of pulp surfaces formed at the Pulp-COOAI can adsorb anionic rosin emulsions by inonic interactions. When pH of the paper stock increased by the addition of an alkaline solution, the ionic linkages, Pulp-COO-AI-Rosin emulsion, were cleaved by decomposition of rosin emulsions and other reasons. Therefore, the retention mechanism of emulsion rosin size/aluminium ion system in wet-end is governed by the immediate formation of ionic linkages at the carboxyl groups in pulp fibers.Next, the properties and chemical structures of size components retained in sheets were studied to elucidate the sizing mechanism of this system. The following analytical techniques were used ; 1) analyzes of cellulase-treated residues of paper-sheets, 2) extractions of paper-sheets with organic solvents, and 3) solid-state 13C-NMR analyzes of paper-sheets prepared with 13C-labled fatty acids used as model compounds of rosin size. The results showed that rosin molecules exsited in sheet as free acid without forming aluminium salts. Furthermore, aluminium ions retained in sheets essmed to govern the distribution patterns or mapping structures of hydrophobic rosin size components on pulp fiber surfaces.