Design of polyarylates containing tert-butyl cyclohexyl bulky side group with high transparency and low dielectric properties

A new kind of novel low dielectric constant ( D k ) and high transparency polyarylate had been synthesized through interfacial polycondensation with 1,1′- bis (4-hydroxybenzene)-4-tert-butylcyclohexane (Bt-BPZ) containing tert-butyl cyclohexyl bulky side group. As we expect, that the introduction of tert-butyl cyclohexyl with large free volume is proved to be an efficient strategy for obtaining low dielectric constant and high transparency polyarylate. The optimal dielectric property is obtained with 90% Bt-PZA in polyarylate (Bt-PZA91), which show a D k as low as 2.14 at 1 MHz. Meanwhile, Bt-PZA91 also demonstrates good transmittance of 81.08%–88.34% at 450 nm and 78.67–88.26 at 400 nm. The cut-off wavelength of Bt-PZA91 is 304 nm, which is 16 nm shorter than commercial product U-100 ( λ c : 320 nm). In addition, the resultant polyarylates showed good comprehensive performance such as T g of 202.2–220.5°C, T d 5% (the initial thermal degradation temperature) of 455.4–468.4°C, tensile strength of 64.7–86.8 MPa and low water absoption (0.41% of Bt-PZA91). Also it was found to can be thermal process, that its convenient thermoplastic processability makes it a great candidate for light-electronic industry, 5G communication, and we believe that Bt-PZA will have a broad application prospect.