改質鈦酸鋇與氧化硼之交互作用對懸浮液之流變行為的影響

Effect of Interactions Between Surface-Modified BaTiO3 and B2O3 On The Rheological Behavior of Suspensions

李怡臻(Yi-Chen Lee)

指導教授 ： 李嘉甄

國立臺北科技大學/工程學院/材料及資源工程系研究所/碩士(2010年)

https://doi.org/10.6841/NTUT.2010.00476

摘要

本研究內容主要探討製備鈦酸鋇電容常用之原料－助熔劑（氧化硼）與水系黏結劑（聚乙烯醇）之間的交互作用，對於鈦酸鋇水系懸浮液之流變行為和分散性質的影響。由實驗結果可得知氧化硼與聚乙烯醇之存在嚴重的膠化作用，而使懸浮液由具流動性之假塑性或牛頓流體轉變為不易流動之膨脹性流體，此一流變行為的變化將不利於後續的漿料製程。雖然由過去之文獻已知添加具有二羥基結構的塑化劑可改善此種不良現象，但塑化劑的添加往往伴隨著薄帶強度的降低且對生胚燒結後的緻密度有負面的影響。針對上述問題，本實驗乃提出一新穎的研究構想：即在不另外添加塑化劑的條件下，藉由表面化學改質技術，使鈦酸鋇粉體衍生出適當濃度的羥基；並利用羥基與氧化硼的化學反應來牽制聚乙烯醇與氧化硼之間的膠化作用，進而使懸浮液的流變行為得以獲得改善。

關鍵字

鈦酸鋇 ； 氧化硼 ； 表面改質

並列摘要

In this paper, we discuss the raw material of barium titanate capacitor. We study in the influence of the interaction between boron oxide and polyvinyl alcohol on rheological behavior and dispersion property of the aqueous solution of barium titanate. From experimental results, we can know the seriously gelation between boron oxide and polyvinyl alcohol affects the pseudoplastic liquid or Newtonian flow to be dilatant flow with badly mobility. This rheological behavior will not good for the next frabration of slurry. There are some papers proposed adding plasticizer which has di-hydroxyl group structure to improve this bad phenomenon but adding plasticizer will decrease the strength and density of green body. For these reasons, we proposed a new concept. We do not add extra plasticizer. In this condition, we use surface-modified technology to make barium titanate powder has suitable consistence hydroxyl. By the chemical reaction between hydroxyl and boron oxide, we pin down the gelation between boron oxide and polyvinyl alcohol. Moreover, we improve rheological behavior of the aqueous solution.

並列關鍵字

Barium titanate ； Boron oxide ； Surface-Modified

參考文獻

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