Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/3331
標題: The Study of Styrene Polymerization in the Presence of Montmorillonite Containing Living Free Radical Initiator
含活性自由基之蒙脫土與苯乙烯聚合研究
作者: 蔡茜茜
Tsia, Chan-Chan
關鍵字: 聚苯乙烯/蒙脫土奈米複合材料;PS/MMT nanocomposite;在位活性自由基聚合;蒙脫土;活性自由基起始劑;接枝;in-Situ Living Free Radical Polymerization;montmorillonite;Living Free Radical Initiator;graft
出版社: 化學工程學系
摘要: 
The purpose of this thesis was to investigate the effect of montmorillonite content, the concentration of TEMPO and reaction time on the synthesis of PS/MMT nanocomposites by in situ living free radical polymerization at 123℃.
Polymerization of styrene in presence of montomorillonite(the montomorillonite's dosage: 1.55 and 3.10 wt%) containing living free radical initiator for 8 hours gave the chemical grafting of PS at 2.28 ~ 2.74 g/1gMMT without adding TEMPO and at 1.08 ~ 1.21 g/1gMMT with 0.005M TEMPO addition. The presence of TEMPO exhibited the linear dependence of versus conversion and showed the “living character” of the polymerization. The polydispersity index of 1.0 ~ 1.2 and the number-average molecular weight (Mn) of 50,000~ 90,000 polymer was obtained for 8-hour reaction period and XRD data showed a weak diffraction between 2.9 and 3.5 nm indicating trace amount of montomorillonite not exfoliated. Without the addition of TEMPO, the polydispersity is between 1.3 and 1.5 and the Mn of 170,000 ~ 230,000 could be obtained for 8-hour reaction period. The d-spacing greater than 4.4 nm after a reaction time of 6 hours was observed. In summary, we have demonstrated that PS/MMT nanocomposites can be directly polymerized via adsorbed living free radical initiator. Diversifying molecular weight and polydispersity of polystyrene grafted on the montomorillonite surface can be prepared by varying the external concentration of TEMPO.

本研究利用蒙脫土/苯乙烯之在位活性自由基聚合 (in-Situ Living Free Radical Polymerization)的方式,在蒙脫土表面吸附活性自由基起始劑,探討在123℃進行聚合反應不同TEMPO外加濃度及蒙脫土含量對反應時間之變化,製備聚苯乙烯/蒙脫土奈米複合材料。
含活性自由基之蒙脫土(蒙脫土含量為1.55 wt%及3.10 wt%)
的苯乙烯聚合,在不外加TEMPO下,則反應8小時後,蒙脫土表
面接枝PS量為2.28∼2.74 g PS/1g MMT;若外加0.005M TEMPO
,則反應8小時之蒙脫土表面接枝PS量為1.08∼1.21g PS/1g MMT
。有外加TEMPO情形下, 對轉化率為線性關係,具活性自由
基聚合的特徵,反應8小時分子量Mn約50,000∼90,000,聚分散
度較窄約在1.0∼1.2,且大部分蒙脫土之層間距大於4.4 nm。若不
外加TEMPO,則反應8小時後,分子量Mn約170,000∼230,000,
聚分散度較寬約1.3∼1.5,於反應6小時後層間距已大於4.4 nm。
研究結果顯示,藉外加TEMPO濃度變化可製備不同分子量與聚分
散度之PS接枝於蒙脫土表面形成PS/MMT奈米複合材料。
URI: http://hdl.handle.net/11455/3331
Appears in Collections:化學工程學系所

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