陰離子共聚物的合成及做為水系鈦酸鋇漿體的分散劑
Abstract
在鈦酸鋇電子陶瓷的製程，要得到穩定性高且分散良好的漿料必須添加分散劑。本篇論文主要合成一種陰離子型聚合物聚(二(二甲基丙烯酯)乙基磺酸鈉/甲基丙烯醯胺) (PMEA)作為分散劑探討，不同分子量的PMEA對於鈦酸鋇水系漿體分散性質的影響。
合成之PMEA以IR和1H-NMR光譜確認其結構，並利用GPC測定得到其重量平均分子量分別為 4.1×105，1.3×105，6.0×104，1.6×104。
添加共聚物對於鈦酸鋇漿體穩定性影響的研究方法有流變行為、沈降體積及粒徑分布測試，並利用界達電位及吸附量等實驗來解釋。經由壓胚及燒結，測量胚體之生胚、燒結密度、介電常數及介電損失。另外，利用ICP-MASS來測量鈦酸鋇漿體中Ba2+的含量。實驗結果發現添加PMEA (Mw =1.3×105) 在鈦酸鋇漿體的分散效果優於其他分子量之聚合物，因PMEA (Mw =1.3×105) 於鈦酸鋇粒子表面有較大的吸附量使粒子有較高的界達電位、較小的粒徑及漿體有較低的黏度並可使粒子分散均勻、堆積緻密而有較高的生胚與燒結密度。最後，添加PMEA能減少漿體中鋇離子的溶出。
In the preparation of a well-dispersed, and stable barium titanate (BT) slurry, the addition of dispersants is essential. This study is to synthesize an anionic copolymer, i.e., poly-[sodium 2-(2-methyl-acryloyloxy) ethansulfonate methacrylamide] (PMEA) as a dispersant for BT slurries. The chemical structure of synthesize PMEAs were varied from the IR and 1H-NMR spectra, and the weight-average molecular weights (Mw) of the copolymers determind by GPC to be 4.1×105，1.3×105，6.0×104 and 1.6×104.The dispersion properties of PMEA were examined by measuring the rheological property, sedimentation, and particle size of BT suspensions. The zeta potential and adsorption experiments were carried out. The green and sintered density of BT compacts were determind. Besides, the barium ions leached from BT particles in aqueous solutions were also measured results indicate that addition of PMEA can reduce the viscosity, stabilize the BT suspensions, reduce the particle size, and make BT compacts with higher green and sintered density, PMEA with Mw of 1.3×105 is more effective because the adsorption amount onto particle was greater and the achieved zeta potential more negative than polymers with other Mw. Finally, PMEA could reduce the leached barium ion in the BT suspensions.
In the preparation of a well-dispersed, and stable barium titanate (BT) slurry, the addition of dispersants is essential. This study is to synthesize an anionic copolymer, i.e., poly-[sodium 2-(2-methyl-acryloyloxy) ethansulfonate methacrylamide] (PMEA) as a dispersant for BT slurries. The chemical structure of synthesize PMEAs were varied from the IR and 1H-NMR spectra, and the weight-average molecular weights (Mw) of the copolymers determind by GPC to be 4.1×105，1.3×105，6.0×104 and 1.6×104.The dispersion properties of PMEA were examined by measuring the rheological property, sedimentation, and particle size of BT suspensions. The zeta potential and adsorption experiments were carried out. The green and sintered density of BT compacts were determind. Besides, the barium ions leached from BT particles in aqueous solutions were also measured results indicate that addition of PMEA can reduce the viscosity, stabilize the BT suspensions, reduce the particle size, and make BT compacts with higher green and sintered density, PMEA with Mw of 1.3×105 is more effective because the adsorption amount onto particle was greater and the achieved zeta potential more negative than polymers with other Mw. Finally, PMEA could reduce the leached barium ion in the BT suspensions.
Description
Keywords
鈦酸鋇, 聚合物, 合成, 分散, 鋇離子溶出, barium titanante, polymer, synthesis, dispersion, leached Ba2+