Preparation and performance of low‐dielectric benzocyclobutene resins containing dicyclopentadiene.

Low‐dielectric‐constant polymer materials are widely used in the electronic industry owing to their unique characteristics. Benzocyclobutene (BCB) resin is one such material with excellent dielectric properties and thermal stabilities. In this work, a novel BCB‐functionalized monomer (DCPDNO‐BCB) was synthesized from 2,6‐dimethyl phenol‐DCPD novolac (DCPDNO) and 4‐Bromobenzocyclobutene through Ullmann coupling. The structure of DCPDNO‐BCB was characterized by 1H NMR, 13C NMR, and ESI‐MS, and poly(DCPDNO‐BCB), obtained by ring‐opening and subsequent Diels–Alder reaction at the appropriate temperature, was found to exhibit low dielectric properties (k = 2.53 at 10 MHz), low water absorption, high thermal stability (Td5 = 430°C), and good film flatness. [ABSTRACT FROM AUTHOR]