Synthesis and Properties of Fluorinated Polyimide Films Based on 1,2,3,4-Cyclobutanetetracarboxylic Dianhydride

Abstract

The alicyclic dianhydrides 1,2,3,4-cyclobutanetetracarboxylic dianhydride(CBDA) was polymerized with four kinds of fluorinated aromatic diamine, 2,2’-bis(trifluoromethyl)-4,4’- diaminobiphenyl(TFDB), 1,4-bis(4-amino-2-trifluoromethylphenoxy)benzene(6FAPB), 1,4-bis(4- amino-2-trifluoromethylphenoxy) diphenyl ether (6FAPE) and 1,4-bis(4-amino-2-trifluoromethyl- phenoxy)diphenyl(6FBAB) respectively, via a two-step polycondensation procedure to prepare four series of fluorinated polyimides(PIs) derived from CBDA. The obtained PIs displayed excellent solubility in aprotic polar solvents, such as NMP, DMAc, DMF and DMSO. These PIs showed good thermal stability with the 10% thermal decomposing temperatures higher than 457 in nitrogen and the glass transition temperatures higher than 267 . In addition, the PI films exhibited good optical transparency in the visible light region(400-700nm) with the transmittance higher than 80% at 450nm, and the PI films showed little absorption at the optocommunication wavelengths of 1.30µm and 1.55µm.

Hyperthermal atomic oxygen durable transparent silicon-reinforced polyimide

“…The diamine 4, 4-bis(4-amino-2-trifluoromethylphenoxy) diphenylether (6FAPE) is polymerized with the dianhydride 1, 2, 3, 4-cyclobutanetetracarboxylic (CBDA) to form poly(amic acid), with a solid content of 15% and a formula shown in Figure 1, and is referred as pristine poly(amic acid) in this study. 52 TSP POSS powders of 0.25 and 0.56 g were dissolved in 15 g poly(amic acid), 53 resulting in transparent Si-reinforced poly(amic acid) solutions with POSS loadings of 10 and 20 wt%, as shown in Figure 2. The Si-reinforced and pristine poly(amic acid) solutions were spun coated on slide glasses at 500 r min À1 for 30 s. The spin-coating speed and time were adjusted in order to get 50-80-mm-thick free-standing films after curing.…”

Transparent Polyimide/Organoclay Nanocomposite Films Containing Different Diamine Monomers

“…Therefore, efforts are now being made to improve these optical properties and the processability of PI. For example, PIs containing trifluoromethyl groups have been synthesized that show a high modulus, low thermal expansion coefficient, and good solubility in conventional organic solvents [9][10][11]. Another method is to use a copolyimide (Co-PI) using a specific monomer.…”

Transparent and organosoluble cardo polyimides with different trans/cis ratios of 1,4‐diaminocyclohexane via aromatic nucleophilic substitution polymerization

“…In order to overcome the drawback of deep coloration of PIs, which is caused by intra‐ and intermolecular charge transfer interactions, many structural modification strategies have been utilized . The most effective approach is to use aliphatic tetracarboxylic dianhydrides or aliphatic diamines, which would enlarge the energy gap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital, and shift the absorption wavelength from the visible region to the ultraviolet (UV) region . For the former, there are many reports focusing on semi‐aromatic PIs derived from alicyclic dianhydrides with different ring sizes .…”