The development of multifunctional
polymeric materials from renewable
resources is of foremost significance from a sustainable development
perspective. In this work, a biobased epoxy monomer (EHCPP) with hard
core structures and multi-arms was prepared from cardanol with hexachlorocyclotriphosphazene,
followed by epoxidation with m-chloroperoxybenzoic
acid (m-CPBA). Then, the epoxy polymer networks were
prepared via the curing process of EHCPP with four thiol monomers
of different thiol groups. The mechanical and thermomechanical properties,
thermal stability, solvent resistance, recyclability characteristics,
and optical behavior of the cardanol-based epoxy resins were systematically
investigated. The results showed that four epoxy resins (EHCPP-2SH,
EHCPP-3SH, EHCPP-4SH, and EHCPP-BDB) not only exhibited excellent
solvent resistance in 10 wt % aqueous solutions of NaOH, HCl, and
NaCl but also showed intrinsic fluorescence, while only the EHCPP-BDB
epoxy resin showed phosphorescence behavior. Recyclability was observed
in the EHCPP-BDB polymer network due to the presence of dynamic reversible
boron ester bonds. These cardanol-based epoxy-thiol polymer networks
open a pathway to explore potential biomass resources for high-performance
multifunctional materials as a replacement for petroleum-based thermosets
in various industrial applications.