Comprehensive properties study of polyimide with fluorinated nanofillers

There is an increasing demand for polyimide (PI) with excellent mechanical properties, good heat resistance, and low dielectric constant in integrated circuits and advanced packaging. Based on this, we report a strategy of tailoring the PI via fluorinated nanofillers modification to improve its mechanical properties, heat resistance, hydrophobicity, and reduce its dielectric constant. Specifically, different fluorinated nanofiller, including fluorinated graphene (FG), fluorinated carbon nanotubes (FCNT), fluorinated carbon black (FCB), and fluorinated graphene quantum dots (FGQD) were introduced into PI matrix to prepared composite films by a simple method of in-situ polymerization, and the effect of different nanofillers on the properties of polyimide was systematically investigated. The results showed that the introduction of fluorinated nanofillers significantly improved the comprehensive performance of the composite films, especially the FGQD. FGQD/PI composite film with 0.5 wt% FGQD exhibits superior tensile strength (145.8 MPa), Young's modulus (2.83 GPa) and elongation at break (45.4%) the best comprehensive performance which are 10.0%, 19.4%, and 32.0% of those of pure PI, respectively. Most importantly, the FGQD/PI composite film shows decreased dielectric constant (from 3.38 to 2.93) at 1 MHz improved hydrophobicity and excellent heat resistance. The FGQD/PI composite film exhibits excellent comprehensive performance, thereby showing the potential in the future development of advanced packaging and microelectronics industry.