High-performance and low-dielectric cyanate ester resin optimized by regulating the structure of linear polyhydroxy ether modifier

Cyanate ester resin (CE) is an ideal candidate for low dielectric constant (low-k) materials in the microelectronic industry, however the incoordination among mechanical, thermal and low-k properties greatly restricts their practical applications. Herein, two kinds of fluorinated polyhydroxy ether (PHE) with or without polyhedral oligomeric silsesquioxane (FPHE, FPHE-POSS) were designed and synthesized by regulating the structure of the linear PHE chains, to modify CE resin for elevating its comprehensive performances. Results reveal that FPHE can improve the mechanical properties and reduce the k of CE resin to some extent owing to its weakly polarizable flexible chains. Whereas FPHE-POSS can not only enlarge the optimization effects from FPHE, but also significantly improve thermostability simultaneously due to the extra-contribution of the heat-resistant rigid skeleton (POSS). Especially, FPHE-POSS₆/CE possesses lower k values (2.48, 1 MHz), superior impact strength (24.59 kJ/m², increased by 65.0 %) and higher glass transition temperature (307.6°C, increased by 18.8°C) as compared with pure CE resin. This work proposed a facile strategy to break through the incoordination among dielectric, thermal, and mechanical properties of CE resin via using weak-polarizable and flexible-rigid linear oligomer, which could be a guidance for advanced researches.