Ultra-low dielectric constant materials with hydrophobic property: Synthesis of poly(aryl ether sulfone) with POSS and biphenyl group in the main chain

A series of novel poly(aryl ether sulfone)s (PESs) with polyhedral oligomeric silsesquioxane (POSS) and biphenyl group in the main chain were synthesized from 4,4′-biphenol, biphenol POSS and 4,4′-bis[(4-chlorophenyl)sulfonyl]-1,1′-biphenyl via a nucleophilic aromatic substitution polycondensation. The structures of the polymers were characterized by infrared, nuclear magnetic resonance, and wide-angle X-ray diffraction spectroscopy. The incorporation of POSS and biphenyl group into PES matrix at various molar percentages of POSS resulted in a dramatic decrease of dielectric constant as well as a significant increase of hydrophobicity. As the content of POSS increased, the dielectric constant decreased from 2.54 to 1.82, while the contact angle can be increased to 122.6°. The thermal properties, crystallinity, solvent resistance, and surface topography were also studied in this article.