Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/3330
標題: (一)波克(Pockels Effect)效應之光電原理與其檢測系統之架設與操作(二)含鎳錯合物聚亞醯胺高分子之物性與結構分析
作者: 葉世傑
關鍵字: 波克效應;電光係數;含鎳錯合物聚亞醯胺;六配位離子錯合物
出版社: 化學工程學系
摘要: 
Abstract
In the first part of this study, a linear electro-optical (EO) measurement was set up by a simple reflection method. A laser beam aims on the glass substrate at an incident angle q. The incident laser beam is linearly polarized with a 45o polarization angle in respect to the incidence plane so that the parallel (p wave) and perpendicular (s wave) polarized optical fields have equal amplitudes. The beam is transmitted through the ITO-coated substrate, the thin film of NLO material, and then reflected by a gold film. The reflected beam propagates through a Soleil-Babinet compensator, an analyzer and then into a detector. A sinusoidal voltage is applied on the NLO film and the modulation of the laser beam is measured using a lock-in amplifier. Using helium-neon laser (λ = 632.8 nm), an EO coefficient of 30.8 pm/V at the wavelength of the He-Ne laser was obtained for a z-cut LiNbO3 crystal, which is comparable to that reported in literature. The set-up of EO-coefficiency measurement was estabilished and it's operation was confirmed.
For the second part of this study, 5,5'-diamino-2,2'-bipyridine was synthesized for preparing high performance polyimides. The polymers can be coordinated with nickel containing complexes such as (NH3)2Ni(mnt) and Ni(tfd)2, and coordination nickel complex-contained polyimides, PI-Ni(mnt) and PI-Ni(tfd) were obtained.
These metal-coordinated polymeric materials exhibit the improved solubility and mechanical property (high Tg's above 200℃). However, the Td's are lower than those of the pristine polyimides.
A metal-complex coordinated polyimide copolymer coPI50.3, was analyzed by UV-vis and NMR because of its better solubility. An absorption maximum was found at 809 nm. This observation implies the existence of anion of Ni(tfd)- . Moreover, the signals due to the hydrogen atoms of bipyridine ring were not detected by 1H NMR. To further clarity the chemical structure of the metal-complex coordinated polyimide, a series of model compounds were synthesized, and they were analyzed by UV-vis, 1H NMR, and elemental analysis. It was found that a paramagnetic six-coordinated Ni2+ center with two Ni(tfd)- as counter ions presents in the nickel-contained polyimides as well as model compounds. The previously expected second-order NLO active four-coordinated square planar bonding structure was not formed. This study also confirmed that, except the NO2-contained bipyridine complex Ni(5NO2bipy)(tfd), nickel metal complexes are in form of second-order NLO inactive six-coordination in either model compounds or polymer.
To investigate the electro-optical property of the push-pull nickel complex contained in bulk material, a guest-host system based on commercially available polysulfone and Ni(5NO2bipy)(tfd) [doping level = 10 wt%] was prepared. An EO coefficient r33 of 0.7 pm/V was obtained after poling at 165 ℃ (7 kV) for 10 minutes.

摘要
在本論文的第一部份,我們成功地架設反射式電光係數(EO coefficient)檢測的儀器。將雷射光的偏振角度固定在與入射面夾45度,使p波(平行入射面)與s波(垂直入射面)的振幅相等,以特定角度θ入射至鍍有ITO透明導電電極的玻璃載體經遇非線性光學材料薄膜,再由鋁製電極層反射,再加一調變電壓(modulation voltage),以Soleil-Babinet compensator調整p波與s波相對相位至相差π/2,雷射光經一分析片,至光偵器,再以鎖相放大器得到訊號。以氦-氖雷射 (波長=632.8nm)入射至z切割LiNbO3晶體測得其電光係數為30.8 pm/V,與先前文獻上所得之電光係數值相當,証實檢測系統架設成功操作無誤。
第二部份製備主鏈配位含鎳聚亞醯胺高分子錯合物,使其有非線性光學性質。首先合成具雙砒碇環的雙胺單體5,5’-diamino-2,2’-bipyridine以製備耐高溫聚亞醯胺高分子(PI),再與兩種含鎳發光團基(NH3)2Ni(mnt)及Ni(tfd)2形成配位錯合物型高分子材料,PI-Ni(mnt)與PI-Ni(tfd)。
製備所得兩系列之含鎳錯合物聚亞醯胺高分子在高溫有好的機械性質(Tg在200 ℃以上) ,但其所預期的熱性質加成性並不如預期,PI-Ni(mnt)系列無明顯增加,而 PI-Ni(tfd)系列增加在10℃左右。含鎳錯合物材料之熱裂解溫度皆不如原本之聚亞醯胺,下降約數十度至一百度左右,其結果與先前4,4’-diamino-2,2’-bipyridine所製備聚亞醯胺及其共聚物之研究有相同的結果。在PI-Ni(tfd)系列中,我們利用合成聚亞醯胺共聚物的方法及選擇溶解度良好之鎳錯合物Ni(tfd)2成功地使形成之材料在常溫下具有良好的溶解度。進一步利用紫外光-可見光(UV-vis)、核磁共振光譜(NMR)、元素分析(EA)等儀器分析其結構。
含鎳錯合物聚亞醯胺共聚物(30%) coPI0.35-Ni(tfd)在UV-vis的吸收峰在809nm,與所製備出之含雙砒碇模型化合物有相同之吸收峰。經文獻比對,材料內疑有Ni(tfd)-的離子存在。再由模型化合物所得之核磁共振光譜,發現含鎳錯合物聚亞醯胺與模型化合物的光譜皆形成順磁性化合物的結果。元素分析數據結果得知,高分子結構以三個雙砒碇配位基跟一個鎳二價金屬離子形成的六配位離子化合物伴以二個Ni(tfd)-為陰離子是主要形成之產物。所以判斷與模型化合物性質相似的含鎳聚亞醯材料並沒有形成所預期之平面四方配位鍵結。
本實驗亦証實其中除了雙砒碇上取代基為-NO2官能基的模型化合物形成具有二次非線性光學性質之推-拉電子結構的平面四方結構外,其他形成的均為不具二次非線性光學性質之鎳六配位離子型錯合物。
為了了解含鎳錯合物之非線性光學性質,我們以購得的高分子polysulfone (Tg = 185℃; 溶於THF中)作為高分子基材以Ni(5NO2bipy) (tfd) (10 wt%)製備賓主系統之高分子薄膜,在經165 ℃及7 kV的高電場極化下所得之薄膜量測所得之r33 = 0.7 pm/V,証明含鎳錯合物材料在光電調變材料應用上之可行性。
URI: http://hdl.handle.net/11455/3330
Appears in Collections:化學工程學系所

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