Novel polyethersulfone dielectric films with high temperature resistance, intrinsic low dielectric constant and low dielectric loss

In this work, a series of fluorene-containing fluorinated polyethersulfone (PES-6AF/BHPF) copolymers with high temperature resistance and intrinsic low dielectric constant (low-epsilon) have been designed and synthesized from 4,4 '-dichlorophenyl sulfone (DCS) and polyphenol. The performance of obtained PES-6AF/BHPF can be controlled and optimized by controlling the copolymers structure. The thermal and dielectric properties of PES-6AF/BHPF were evaluated comprehensively. The obtained PES-6AF/BHPF copolymers show high glass transition temperatures (T-g) ranging from 200 to 260 degrees C, and 5% weight loss temperatures (T-d5%) is stable up to 500 degrees C. The epsilon value of PES-6AF/BHPF-0% and PES-6AF/BHPF-100% are as low as 2.1 and 2.3, and the loss tangent (tan delta) are only 0.0088 and 0.003 at 1 kHz, respectively. In addition, all of PES-6AF/BHPF films show good stability of dielectric properties in high temperature conditions. More importantly, the PES-6AF/BHPF copolymers are soluble in common solvents (such as DMAc, NMP, DMF, THF). The PES-6AF/BHPF copolymers are amorphous and can be easily cast into transparent and flexible films with tensile strength of 62-74 MPa and an elongation at break of 13.3-15.8%. The outstanding comprehensive properties made it possible to be the most promising polymer candidates for high-performance interlayer dielectrics.

Automated summary

A series of fluorene-containing fluorinated polyethersulfone (PES-6AF/BHPF) copolymers with high temperature resistance and intrinsic low dielectric constant have been designed and synthesized, showing excellent thermal and dielectric properties. The copolymers exhibit high glass transition temperatures and stable weight loss temperatures, as well as low dielectric constants and loss tangents, making them promising candidates for high-performance interlayer dielectrics.