Optically Transparency and Light Color of Novel Highly Organosoluble Alicyclic Polyimides with 4-tert-Butylcyclohexyl Group
✍ Scribed by Der-Jang Liaw; Ching-Cheng Huang; Wen-Hsiang Chen
- Publisher
- John Wiley and Sons
- Year
- 2006
- Tongue
- English
- Weight
- 186 KB
- Volume
- 207
- Category
- Article
- ISSN
- 1022-1352
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✦ Synopsis
Abstract
Summary: Novel optically transparent and highly organosoluble alicyclic polyimides derived from bulky alicyclic diamine containing trifluoromethyl group on either side, 1,1‐bis[4‐(2‐trifluoromethyl‐4‐aminophenoxy)phenyl]‐4‐tert‐butylcyclohexane (BTFAPBC), were prepared. All polymers showed excellent solubility in various organic solvents like N‐methyl‐2‐pyrrolidinone (NMP), N,N‐dimethyl acetamide (DMAc), N,N‐dimethyl formamide (DMF), pyridine, cyclohexanone, and γ‐butyrolactone. The cut‐off wavelength and 80% transmission wavelength for polyimides ranged from 362 to 407 nm and 436 to 492 nm, respectively. Polyimides with alicyclic tert‐butylcyclohexyl cardo and trifluoromethyl substituents exhibited low dielectric constants ranging from 3.38 to 4.07 (at 1 KHz). Inherent viscosities of the polyimides were found to be in the range of 0.52–1.00 dL · g^−1^. Polyimides showed glass transition temperatures in the range of 231–262 °C, and possessed a coefficient of thermal expansion (CTE) of 66–79 ppm · °C^−1^. Thermogravimetric analyses of the polyimides revealed high thermal stability and decomposition temperature more than 450 °C in nitrogen atmosphere. The 10% weight loss temperature was found to be in the range of 453–544 and 413–502 °C in nitrogen and air atmospheres, respectively. The polyimide films had a tensile strength ranging from 84 to 100 MPa. The elongation at break varied from 6 to 12% and the tensile modulus varied from 1.1 to 2.1 GPa.
Synthesis of diamines, BTFAPBC, BTFAPAd, and BTFAPTC.
magnified imageSynthesis of diamines, BTFAPBC, BTFAPAd, and BTFAPTC.