Cross Linkable Hydrocarbon Resins Bearing β-Styryl Moieties and Allylic C-H Bonds: Synthesis, Curing Behavior and Performance for CCL Applications

Currently, hydrocarbon resins are mainly classified into styryl-based and benzocyclobutene (BCB)-based systems. Styryl-based hydrocarbon resins are cost-effective but generally show limited heat resistance, whereas BCB-based resins have relatively high cost. Moreover, these two systems seem to have mismatched curing temperature windows and limited mutual compatibility. Herein, we develop a cross-linkable hydrocarbon resin derivative BP-TVCH from biphenyl and 1,2,4-trivinylcyclohexane, rich in β-styryl moieties and allylic C-H bonds. Upon curing, the benzene rings are incorporated into the cross-linked network. The β-styryl moieties undergo homopolymerization, while the allylic C-H bonds participate in curing through chain-transfer reactions. The resulting resin can be co-cured with both styryl-based and BCB-based hydrocarbon resins. When composited with styrene-terminated polyphenylene ether (OPE-2st), the resulting CCL exhibits a dielectric loss of 0.00101–0.00105 and a high glass transition temperature (Tg) of up to 277 °C.