摘要
摘要 本研究主要是延續本實驗室所研發的兩性型高分子，並探討其對鈦酸鋇漿體的分散情形，與商業型分散劑甲基丙烯酸鈉鹽(PMAA-Na)做一個比較。而PDAE係以β-羧基-N-(3-二甲基氨丙基)丙烯醯胺和氯醋酸鈉反應生成β-羧基-N-(3-二甲基氨丙基-N-乙酸鈉)丙烯醯胺單體，在與丙烯醯胺經自由基反應而得，合成之DAE單體及PDA E高分子聚合物均以H1-NMR確認結構並利用GPC測量PDAE之分子量。 本研究利用測定鈦酸鋇漿料的黏度、粒徑分佈、沉降體積、與粒子表面電位等來評估分散劑在漿料中的分散效果。另外，漿料的鋇離子的溶出量以及胚體的密度與電性亦予以測定。結果顯示PDAE (重量平均分子量 = 4 x 10 5)可以有效的分散鈦酸鋇漿料，使得漿料的黏度降低、穩定度提高、與粒子粒徑變小。PDAE在漿料中的分散效果與PMAA-Na相當或更好，而且添加PDAE的漿料之鋇離子的溶出量明顯少於添加PMAA-Na者。原因是PDAE與PMAA-NA兩者再結構上的差異而造成不同的吸附分散行為。因此，添加PDAE的鈦酸鋇漿體在燒結胚體的密度以及介電常數值均較添加PMAA-NA者高，而介電損失則較低。
關鍵字
分散劑並列摘要
Abstract This study continues the research and development of an amphibious water-soluble copolymer, i.e., poly(α-(N,N-dimethyl-N-(3-(β-carboxylate) acrylamino) propyl) ammonium ethanate)/acrylamide (PDAE), as a new dispersant for aqueous BaTiO3 slurries. PDAE was prepared from α-(N,N-dimethyl-N-(3-(β-carboxylate) acrylamino) propyl) ammonium ethanate (DAE) and acrylamide through free radical polymerization. DAE was prepared from reacting β-carboxylate-N-(3-dimethyl-amino- propyl) acrylamide with dimethyl-1,3-propylene diamine. The prepared DAE and PDAE were verified from their H-NMR spectra, and the molecular weight of PDAE was measured by GPC. The dispersing effectiveness of PDAE on aqueous BaTiO3 slurries were examined and discussed from the resulting viscosity, sedimentation volume, particle size distribution of pastes, and the zeta-potential of BaTiO3 particles. Besides, the concentration of dissoluted Ba2+ in the slurries, the density and electrical properties of sintered compacts were also measured. The results indicate that PDAE (weight-average molecular weight = 4 x 10 5) shows good dispersing ability because this copolymer can reduce the slurry viscosity, make the slurry more stable, and result in smaller particle size. Compared to a commercial dispersant, sodium salt of polymethylacrylic acid (PMAA-Na), it is as effective or even better in preparing stabilized suspensions. More importantly, PDAE can reduce the leached Ba2+ concentration. This is related to the chemical nature and adsorption behavior of this copolymer. Consequently, the BaTiO3 slurries with PDAE shows higher sintered density, higher dielectric constant, and lower dielectric loss than those with PMAA-Na.
並列關鍵字
disant參考文獻
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