A Facile Method for Preparing Fluorinated Poly(aryl ether)s Toward High-Frequency Low Dielectric Materials.

Area of Science:

• Polymer Chemistry
• Materials Science
• Organic Synthesis

Background:

• Poly(aryl ether)s are widely used in advanced materials due to their excellent thermal and mechanical properties.
• Developing novel poly(aryl ether)s with enhanced properties, particularly for high-frequency applications, remains a significant challenge.
• Fluorinated polymers often exhibit desirable characteristics such as low dielectric constants and low moisture absorption.

Purpose of the Study:

• To synthesize novel fluorinated monomers and polymers with potential for high-frequency applications.
• To investigate the structure-property relationships of the synthesized fluorinated poly(aryl ether)s.
• To evaluate the performance of the fluorinated polymers, focusing on thermal stability, water uptake, and dielectric properties.

Main Methods:

• Synthesis of two fluorinated monomers (M1 and M2) based on pentafluorostyrene via aromatic nucleophilic substitution (SNAr) reaction.
• Conversion of monomers to fluorinated poly(aryl ether)s through thermo-crosslinking.
• Characterization of polymer properties, including thermal stability (T5d), water uptake, dielectric constant (Dk), and dielectric loss (Df).

Main Results:

• Monomers M1 and M2 were synthesized with high yields (up to 90%) at room temperature.
• The cured M2 polymer, with higher fluorine content, exhibited a high 5% weight loss temperature (T5d) of 465 °C.
• Cured M2 demonstrated excellent performance with low water uptake (0.17%) and a low dielectric constant (Dk = 2.46) and dielectric loss (Df = 3.65 × 10⁻³ at 10 GHz).

Conclusions:

• A facile and effective method for preparing high-performance fluorinated poly(aryl ether)s was established.
• The synthesized fluorinated poly(aryl ether)s, particularly M2, show superior properties compared to existing materials.
• These fluorinated polymers are well-suited for demanding high-frequency communication applications.