以三臂鏈及六臂鏈星狀聚苯乙烯為成孔劑製備孔隙性聚醯亞胺及其性質探討

Preparation and characterization of porous polyimides using 3-armed and 6-armed star-like polystyrene as porogens

劉偉強(Wei-Chiang Liu)

指導教授 ： 鄭俊麟 ； 王立義

中原大學/工學院/化學工程研究所/碩士(2009年)

https://doi.org/10.6840/cycu200901211

摘要

在本研究中，我們利用原子轉移自由基聚合反應合成出不同分子量的三臂鏈及六臂鏈星狀聚苯乙烯作為成孔劑，並由GPC數據得到其分子量分佈均小於1.2。隨後將之掺混在pyromellitic dianhydride (PMDA)及 4,4-methylenedianiline (MDA)聚醯胺酸中，加熱環化後，再將聚苯乙烯進行熱裂解而製備出多孔性聚醯亞胺薄膜。
我們使用AFM來量測材料的表面型態，可看到隨著作為成孔劑的聚苯乙烯含量的提高，膜材的表面粗糙度也會些微的增加。由SEM來觀察材料的剖面型態，由實驗結果可看到，隨著所添加的成孔劑含量增加，內部的會由於孔隙的變多而結構會較為鬆散。
由TGA的結果可得到5%熱裂解溫度會隨著成孔劑的分子量增加和含量的提高而稍微下降。在DSC的結果上，玻璃轉移溫度亦會隨著成孔劑的分子量提高以及添加量的增加而下降。由TMA的測量結果發現，PMDA-MDA聚醯亞胺薄膜的熱膨脹係數與孔洞的多寡並無明顯關係。
在介電性質的測量上，實驗結果顯示，在三臂鏈及六臂鏈的星狀聚苯乙烯為成孔劑下，我們都可發現，介電常數會隨著添加量的提高，而下降的越多，且分子量提高也會讓介電常數下降的程度增加。我們在使用六臂鏈星狀聚苯乙烯為成孔劑時，所製備的PMDA-MDA聚醯亞胺薄膜其在介電性質及熱性質上的表現都會比使用三臂鏈星狀聚苯乙烯為成孔劑所製備出來的PMDA-MDA聚醯亞胺薄膜要佳。

關鍵字

孔洞 ； 聚醯亞胺 ； 星狀聚苯乙烯

並列摘要

In this study, we used atom transfer radical polymerization (ATRP) method to synthesis 3-armed and 6-armed star-like polystyrene. GPC data showed the molecular weight distribution of star-like polystyrene were less than 1.2. Then star-like polystyrenes were added into poly(amic acid) (PAA) solution (pyromellitic dianhydride (PMDA) and 4,4-methylenedianiline (MDA)) as porogens. The PAA solution that contained porogens was cast onto glass side by spin-coated and then used thermal imidization for converting PAA to polyimide. When it ensured imidization, star-like polystyrenes were thermally decomposed to form porous polyimide.
We used SEM to observed cross section structure of porous polyimide and the surface roughness was measured by AFM. The results showed an increase of the porogen content and the surface roughness would be increased.
The thermal decomposition temperature and the glass transition temperature of polyimide were decreased when the porogen content or/and molecular weight increased. The results showed that the coefficient of thermal expansion of polyimide had no obvious effect with number of pore.
The results of the dielectric constant of polyimide showed decreased when increasing content or/and molecular weight of 3-armed and 6-armed star-like polystyrene. In thermal and dielectric properties, preparation of porous polyimides using 6-armed star-like polystyrene as porogen would better than using 3-armed one.

並列關鍵字

star polystyrene ； porous ； polyimide

參考文獻

1. J. O. Simpson, A. K. Clair, Thin Solid Films, 308, 475 (1997).

2. P. S. Alegaonkar, A. B. Mandale, S. R. Sainkar, V. N. Bhoraskar, NuclearInstruments & Methods in Physics Research Section B-Beam Interactions with Materials and Atoms, 194, 281 (2002).

3. L. Jiang, J. Liu, D. Wu, H. Li, R. Jin, Thin Solid Films, 510, 241 (2006).

4. G. Maier, Progress in Polymer Science, 26, 3 (2001).

7. T. Takeichi, M. Zuo, A. Ito, High Performance Polymers, 11, 1 (1999).