側鏈含三苯胺結構之芳香族聚醯胺與聚醯亞胺的合成與電致變色性質之研究

Synthesis and Electrochromic Properties of Aromatic Polyamides and Polyimides Bearing Pendent Triphenylamine Units

周于丹(Yu-Tan Chou)

指導教授 ： 蕭勝輝

國立臺北科技大學/工程學院/化學工程研究所/碩士(2012年)

https://doi.org/10.6841/NTUT.2012.00382

摘要

本論文在探討三種新型懸掛三苯胺側鏈基的芳香族二胺單體分別為4-(3,5-diaminobenzamido)triphenylamine (4)、4-(3,5-diaminobenzamido)-4',4'-di- tert-butyltriphenylamine (t-Bu-4) 和 4-(3,5-diaminobenzamido)-4',4'-dimethoxy triphenylamine (MeO-4)及由它們衍生的芳香族聚醯胺與聚醯亞胺之合成及特性。三個系列具電活性的聚醯胺是由這三種二胺單體分別與三種芳香族二羧酸經由磷酸化聚縮合反應而製得。這些聚醯胺均很容易溶於極性的有機溶劑當中，並可由它們的溶液塗佈及烘乾後製成具可撓曲性、強韌的薄膜。這些聚合物的玻璃態轉移溫度 (Tg) 在269-294 oC之間，受熱溫度超過470 oC才會達到10 %的重量損失，顯示它們具備良好的熱安定性。由二胺 t-Bu-4 與 MeO-4 所衍生的聚醯胺具有可逆的電化學氧化還原特性，它們的薄膜在電化學氧化還原的過程中會伴隨著明顯的顏色變化並具有高的光學對比度及電致變色穩定性。我們並以光譜電化學的量測結果來解釋它們的電致變色行為。由二胺 4 所衍生的聚醯胺在氧化的過程中所生成的三苯胺自由基陽離子會產生電偶合反應形成聯苯胺 (benzidine) 結構，此種新結構會使聚合物多一種氧化態及顏色變化。
此外，我們也用上述三種二胺單體分別與 4,4-oxydianiline (ODA) 混合再與兩種二酐 DSDA 及 6FDA 進行開環加成聚合得到聚醯胺酸，然後再經由化學閉環得到六種聚醯亞胺共聚物。這些聚醯亞胺均易溶於極性溶劑中，並且可由它們的的溶液塗佈鑄成具可撓曲性、強韌的薄膜。這些聚醯亞胺展現出優異的熱穩定性，其 Tg 值在269-294 oC之間。由高分子薄膜的循環伏安研究發現這些聚醯亞胺同時擁有p-和n-可掺雜特性並且具有多顏色的電致變色現象。與聚醯胺類似，由二胺 t-Bu-4 與 MeO-4 所衍生的聚醯亞胺具有可逆的電化學氧化還原特性，它們的薄膜在電化學氧化還原的過程中會伴隨著明顯的顏色變化並具有高的光學對比度及電致變色穩定性。由二胺 4 所衍生的聚醯亞胺在氧化的過程中所生成的三苯胺自由基陽離子也會產生電偶合反應形成聯苯胺的結構，此種新結構也會使聚醯亞胺多出一種氧化態及顏色變化。

關鍵字

聚醯胺 ； 聚醯亞胺 ； 三苯胺 ； 電化學 ； 電致變色 ； 光譜電化學

並列摘要

This thesis describes the synthesis and properties of three new aromatic diamine monomers with pendent triphenylamine group including 4-(3,5-diaminobenzamido)triphenylamine (4), 4-(3,5-diaminobenzamido)-4',4'-di- tert-butyltriphenylamine (t-Bu-4) and 4-(3,5-diaminobenzamido)-4',4'-dimethoxy- triphenylamine (MeO-4) and their derived aromatic polyamides and polyimides. Three series of electroactive polyamides were synthesized from these three diamines with three aromatic dicarboxylic acids via the phosphorylation polyamidation reactions. The resulting polyamides are easily soluble in polar organic solvents and can be solution-cast into flexible and strong films. They exhibited good thermal stability with glass-transition temperatures (Tg) in the range of 269-294oC and 10% weight-loss temperatures in excess of 470 oC. The polyamides derived from diamines t-Bu-4 and MeO-4 exhibited reversible electrochemical oxidation, accompanied by strong color changes with high contrast ratio and electrochromic stability. The remarkable electrochromic behavior of the polymer film is clearly interpreted on the basis of spectroelectrochemical studies. For the polyamides derived from diamine 4, the triphenylamine radical cations formed during the oxidative process will dimerize to a benzidine structure, leading to an additional oxidation state and color change.
Aromatic polyimides with pendent triphenylamine group were synthesized from equimolar mixture of 4,4'-diaminodiphenyl ether and each of the newly synthesized diamines with two tetracarboxylic dianhydrides (DSDA and 6FDA) via a conventional two-steps procedure that included a ring-opening polyaddition to give poly(amic acid)s, following by chemical cyclodehydration. These polymers exhibited good solubility in polar organic solvents and could be solution-cast into tough and flexible polymer films. They showed excellent thermal stability, with Tg values in the range of 284-309 oC. Similar to that of polyamides, the polyimides derived from diamines t-Bu-4 and MeO-4 exhibited reversible electrochemical oxidation, accompanied by strong color changes with high contrast ratio and electrochromic stability. For the polyimides derived from diamine 4, the triphenylamine radical cations formed during the oxidative process also could couple to a benzidine structure, leading to an additional oxidation state and color change.

並列關鍵字

polyamides ； polyimides ； triphenylamine ； electrochemistry ； electrochromism ； spectroelectrochemistry

參考文獻

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