Organosoluble, low‐dielectric‐constant fluorinated polyimides based on 9,9‐bis[4‐(4‐amino‐2‐trifluoromethyl‐ phenoxy)phenyl]xanthene

Abstract

A new trifluoromethylated bis(ether amine) monomer, 9,9-bis[4-(4-amino-2-trifluoromethylphenoxy)phenyl]xanthene (BATFPX), was prepared through the nucleophilic aromatic substitution reaction of 2-chloro-5-nitrobenzotrifluoride and 9,9-bis(4-hydroxyphenyl)xanthene in the presence of potassium carbonate, followed by catalytic reduction with hydrazine and Pd/C in ethanol. A series of novel fluorinated polyimides were synthesized from BATFPX with various commercially available aromatic tetracarboxylic dianhydrides by one-step polycondensation in m-cresol. The resulting polyimides were readily soluble in many organic solvents such as N,N-dimethylacetamide and tetrahydrofuran, and afforded transparent, flexible and strong films with low moisture absorption (0.28-0.51%), low dielectric constant (2.85-3.26 at 1 MHz) and good optical transparency with UV-visible absorption cut-off wavelengths at 352-410 nm. All the polyimides were amorphous and exhibited high thermal stability, with glass transition temperatures of 282-330 • C, 5% weight loss temperatures above 520 • C in nitrogen or air and char yields higher than 55% at 800 • C in nitrogen. Also, these polyimides had good mechanical properties with tensile strengths of 93-118 MPa, elongations at break of 9-16% and initial moduli of 2.07-2.58 GPa.

Synthesis and characterization of fluorinated polyimides derived from 1,4-bis-[4-amino-2-(trifluoromethyl)-phenoxy] benzene/tetrafluoride benzene

“…[13][14][15][16][17][18][19][20][21] At the same time, the existence of bulky substituent moieties could increase the free volume and decrease the dielectric constants and water absorptions. And the PIs derived from 9,9-bis [4-(4-amino-2-trifluoromethyl-phenoxy) phenyl] xanthene [22] and 2,2′-bis(trifluoromethyl)-4,4′-diaminobiphenyl [23] confirmed it. However, to the best of our knowledge, the research related to the influence of fluorination of the benzene on the properties of PIs was rarely made.…”

Synthesis and characterization of trifluoromethylated poly(ether–imidazole–imide)s based on unsymmetrical diamine bearing carbazole and imidazole chromophores in ionic liquids: Study of electrochemical properties by using nanocomposite electrode

“…The data from thermal analysis indicated that the resulting polymers exhibited fairly high thermal stability. This explains that introduction of strong electron negativity of -CF 3 groups might have enhanced the polarity of the polymer, which should restrict the movement of polymer-link and led to better thermal stability [37,38]. Fig.…”

Synthesis and characterization of novel fluorinated pyridine-based polyimides derived from 4-(4-trifluoromethylphenyl)-2,6-bis(4-aminophenyl)pyridine and dianhydrides

“…37–40 In our previous study, it was found that incorporating rigid 2,6-diphenylpyridyl unit and bulky 4-trifluoromethylphenyl pendent group, based on a diamine monomer 4-(4-trifluoromethylphenyl)-2,6-bis(4-aminophenyl)pyridine ( TFMPBPP ), 41 into the polyamide could effectively improve its solubility and processability, while not deteriorating positive properties. Herein, as part of our continuing efforts on the preparation of soluble, easily processable PIs with high thermal stability and optical transparency for advanced optoelectronics applications, 42,43 we report the synthesis and basic characterization of novel PIs derived from TFMPBPP, which was polymerized with five commercial dianhydrides to produce the corresponding fluorinated pyridine-based PIs. The obtained polymers were systematically investigated to measure the general properties, such as solubility, thermal stability, and optical transparency property, as well as their mechanical property and water uptakes in this article.…”