2,2'-Bis(trifluoromethyl)benzidine (TFMB), CAS number 341-58-2, a fluorinated benzidine derivative, has two trifluoromethyl substituents at 2 and 2'-position. 2,2'-Bis(trifluoromethyl)benzidine is rigid and aromatic, which is desired for synthesizing high surface area metal organic frameworks (MOFs) and covalent organic frameworks (COFs). Owing to its rigidity, the polyimides containing the repeating units of TFMB have high thermal resistance and low linear thermal expansion coefficient (23.4 × 10−6/K from 50 to 250 °C). The two fluoromethyl groups have strong electron withdrawing effect, reducing the electron delocalization of the π orbital on the fully conjugated polymer backbone. This effect leads to significantly more transparent polyimide films compared to those with methyl substituents.
Due to the high transparency, the polyimides are used for solar cell encapsulation with MOFs cluster light diffusers (6.6% enhancement in power conversion efficiency). Flexible solar cells supported by these mechanically robust polyimide substrates maintain 97% initial efficiency after 5000 bending cycles.
Multiple functional groups
For facile synthesis
Fluorinated diamine building block
For polyimides, COFs, and solar cells
Worldwide shipping
Quick and reliable shipping
High purity
>99% High purity