The invention relates to a curable resin that represents an excellent substitute for phenolic resins and is therefore able to replace phenolic resins in all applications in which they are used. Said resin is characterised in that it comprises: (1) at least one prepolymer resulting from the prepolymerisation of a compound A comprising at least one aromatic or heteroaromatic ring, a first group —O—CH2-C?CH and at least one second group selected from the groups —O—CH2-C?CH2 and —CH2-CH?CH2, said groups being carried by the at least one aromatic or heteroaromatic ring; and (2) a compound B comprising at least two thiol groups (—SH). The invention also relates to a material obtained by curing said curable resin, and in particular to an ablative composite material. The invention further relates to a material obtained by curing said curable resin.