Moving from PO its longer chain variants BO (run #1) and DO (run #2) results in a slight improvement of linkage selectivity, while as expected lowering the glass transition temperature from 30ºC for the PO terpolymer to -23ºC for the DO terpolymer. As for PO, addition of more sulfur to the initial monomer feed ratio (run #3) results in an increase to 97% selectivity. Moving to bicyclic CHO (run #4) results in 76% linkage selectivity and an increased Tg of 85ºC and both can be attributed to the rigidity of the cyclohexyl backbone. Mechanistically this leads to a strained bicyclic intermediate upon backbiting thereby disfavouring O/S exchange and S8 incorporation. Nevertheless an increase in sulfur loading achieves near perfect linkage selectivity (run #5) which has been challenging to achieve in related sulfurated polymerisations. In line with this interpretation the geminally disubstituted epoxide IBO (run #7) that favours backbiting due to the Thorpe-Ingold effect leads to an increase in sequence selectivity compared to monosubstituted PO. Notably IBO does not contain diastereotropic protons, simplifying H NMR analysis that again supports an increase in longer oligosulfide links with sulfur loading (run #8, see ESI Figure ) by this complementary technique. Moving to SO (run #9 and #10) an intrinsically challenging monomer in this class of polymerisation also results in successful polymer formation albeit with no head-to-head or tail-to-tail regioselectivity. As it has been previously reported that SO ring opening occurs both at the head CHPh and tail CH2 position of the epoxide this demonstrates that the regioselectivity of the initial epoxide ring-opening explains the head-to-head-alt-tailto-tail regioselectivity observed for PO and others epoxide thus further supporting the mechanistic hypothesis. Even epichlorohydrin bearing electrophilic CH2Cl groups is tolerated albeit with decreased molecular weight and broadened polydispersities (run #18) indicating some branching due to co-occurring nucleophilic substitution with the side chains. Motivated by this circumstance we employed a bifunctional epoxide DEO (run #19) which indeed yields an insoluble network with PTA and S8. We could even extend this to epoxidized soybean oil yielding crosslinked network with a very low Tg of -40 ºC. Despite of the insolubility these networks in good solvents for linear terpolymers (THF, CHCl3) they can be compression moulded into brittle films at 80ºC due to the dynamicity of the incorporated -Sx-bonds.