Xiao, Peng; He, Xiaojie; Zheng, Feng; Lu, Qinghua published the artcile< Super-heat resistant, transparent and low dielectric polyimides based on spirocyclic bisbenzoxazole diamines with Tg > 450°C>, Name: Cyclobuta[1,2-c:3,4-c’]difuran-1,3,4,6(3aH,3bH,6aH,6bH)-tetraone, the main research area is polyimide spirocyclic bisbenzoxazole diamine glass transition temperature.
Maintaining ultra-high heat resistance and sufficient colorless transparency at the same time is a challenge for polymer materials because of conflicting design principles, but such materials are urgently needed for some optoelectronic devices. In this study, four new isomeric diamines with a spirocyclic bisbenzoxazole structure were synthesized, and their polyimides were prepared by condensation with com. diamines, 4,4′-(hexafluoroisopropylidene) diphthalic anhydride (6FDA) and cyclobutane-1,2,3,4-tetracarboxylic acid dianhydride (CBDA) followed by chem. imidization. The resultant polyimide (PI) films have excellent optical transparency with cut-off wavelengths in the range of 346 nm-380 nm, and 85%-90% transmittance at 550 nm. Also, these PIs possessed excellent solubility in common organic solvents, even in low-boiling-point solvents, such as chloroform, dichloromethane and THF. Most importantly, the colorless polyimides displayed a super-high glass transition temperature (Tg), high thermal stability, and favorable mech. properties, and their Tg reached 491°. The polyimides possessed low moisture absorptions of 0.52%-0.61% and low dielec. constants (Dk) of 2.32-2.93. The excellent comprehensive properties of the spirocyclic bisbenzoxazole-containing colorless transparent polyimides (CPIs) render these materials promising candidates for optical and optoelectronic applications.
Polymer Chemistry published new progress about Absorption. 4415-87-6 belongs to class tetrahydrofurans, and the molecular formula is C8H4O6, Name: Cyclobuta[1,2-c:3,4-c’]difuran-1,3,4,6(3aH,3bH,6aH,6bH)-tetraone.
Referemce:
Tetrahydrofuran – Wikipedia,
Tetrahydrofuran | (CH2)3CH2O – PubChem