TFT-LCD廢玻璃/氟化鈣污泥熱處理資材化為絕緣玻璃陶瓷之研究

Materialization Study on Transformation of Insulated Glass-Ceramic from TFT-LCD Waste Glass and CaF2 Sludge by Thermal Treatment

范振軒(Chen-Hsuan Fan)

指導教授 ： 李公哲

國立臺灣大學/工學院/環境工程學研究所/碩士(2010年)

https://doi.org/10.6342/NTU.2010.00836

摘要

本研究係以影像顯示產業製程廢棄物之Thin Film Transistor Liquid Crystal Display (TFT-LCD)廢玻璃與氟化鈣污泥經高溫熱處理製成優良介電性質(低介電常數、高介電強度)、機械性質(高抗壓強度、高抗折強度)與高經濟附函價值之絕緣玻璃陶瓷材料。研究共分三階段進行，第一階段為對廢玻璃與氟化鈣污泥進行基本性質分析，與不同廢棄物比例對熔流溫度之影響々第二階段為調查成核劑與調質劑對軟化溫度與晶相之影響々第三階段根據前兩階段實驗結果，為針對可形成MgO-Al2O3-SiO2 (MAS)系玻璃陶瓷系統之結晶物(堇青石)之配比，研析溫度對其介電性質與機械強度之影響，評估將廢玻璃與氟化鈣污泥作為絕緣玻璃陶瓷原料之合適性。
實驗結果顯示氟化鈣污泥與廢玻璃比為5〆5時有最低熔流溫度1064℃，此時鹽基度(CaO/SiO2)為0.83。廢玻璃與氟化鈣比為3〆7之配比經熔融、水冷程序所得之無晶質玻璃粉末，可得軟化溫度為899℃(低於其它配比250℃以上)。添函TiO2成核劑可使結晶放熱峰降低且有效降低玻璃之熔流溫度，但對機械性質並無明顯提升之效用且對介電性質有不良之影響。添函MgO 10%-20% (w/w)，可使廢玻璃與氟化鈣之混合配比析出MAS系玻璃陶瓷系統之堇青石結晶相。
考量機械性質、優良介電性質，且在熱處理過程不至發生形變之最適成形條件，本研究建議使用氟化鈣污泥與TFT-LCD廢玻璃比為3〆7並添函15%MgO(w/w)之配比，經熔融、水冷程序所得之玻璃粉末於920℃進行熱處理，可得抗折強度為80.62 Mpa、抗壓強度為220Mpa、介電損失因子為0.06，介電強度為7.35kv/mm 之絕緣玻璃陶瓷，具有優良機械性質與介電性質，且符合絕緣陶瓷之要求規範，可確定其具資材化成絕緣玻璃陶瓷之潛力。

關鍵字

TFT-LCD廢玻璃 ； 氟化鈣污泥絕緣玻璃陶瓷 ； MAS ； 介電性質

並列摘要

This study aimed to use thin film transistor liquid crystal display (TFT-LCD) waste glass and calcium fluoride (CaF2) sludge from optoelectronics industrial wastes as treated materials to produce excellent dielectric (low dielectric loss factor and high dielectric strengths ) and mechanical properties (high flexural strengths and high compressive resistance) by thermal treatment.
There were three experimental stages in this study. (1) Analyzing the fundamental characteristics of wastes, and investigating the effects of varies CaF2/ waste glass ratios on the pouring temperature (PT). (2) The effects of nucleating agent (TiO2) and additives (MgO) on lowest softening temperature (ST) and crystal phases. (3) Based on the results in first and second stages, the third stage focused on the ratios that could potently form the cordierite of MgO-Al2O3-SiO2 (MAS) glass-ceramics system, the effects of temperature on mechanical properties and dielectric properties as well as the assessment of appropriateness of material reutilized from TFT-LCD glass combined with CaF2 sludge as raw materials of insulating glass-ceramic.
The result showed that the lowest PT corresponding to a basicity (CaO/SiO2) of 0.83 under a ratio of CaF2 sludge-waste glass as 50%-50% by weight. The amorphous glass powder prepared by melting and quenching process in the proportion CaF2 sludge-waste glass 30%-70% by weight showed the ST of 899℃ (250℃ lower than other proportions).
TiO2 addition resulted in the decrease of exothermic peak and melting temperature of amorphous glass powder, however it can cause deterioration of dielectric properties and insignificant improvement in mechanical properties. In addition, cordierite phase of the MAS system can be produced by 10% - 20% MgO
III
addition.
The optimal operational conditions to utilize wastes as the potential as insulating glass-ceramics could be found as follows. (1) Co-melting CaF2 sludge and waste glass were in the ratio of 3:7 with MgO addition of 15% by weight. (2) Obtaining amorphous glass powder via quenching treatment (3) One-step sintering and heat treatment at 920℃ for 4h was employed to obtain glass-ceramics. The sintered materials could meet the required properties for insulating glass-ceramics. i.e. they showed flexural strengths up to about 80 Mpa, compressive resistance up to about 220 Mpa, a dielectric loss factor of 0.06 and a dielectric strengths of 7.35 kv/mm.

並列關鍵字

TFT-LCD Waste Glass ； Calcium Fluoride Sludge ； Insulated Glass-Ceramic ； MAS system ； Dielectric properties

參考文獻

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