The terpolymer of CO₂, 1,3-butadiene and epoxides is synthesized by cationic ring-opening copolymerization of α-ethylidene-δ-vinyl-δ-valerolactone (EVL), an intermediate derived from CO₂ and 1,3-butadiene, with epoxides. The resulted poly(ester-ether) with moderate molecular weight bears all the C=C double bonds derived from 1,3-butadiene, enabling post-polymerization modification and functionalization. Photoinitiated crosslinking through these preserved C=C double bonds produces network with fluorescence and degradation properties.

Comprehensive Summary

The utilization of carbon dioxide (CO₂) as a C1 feedstock is consistently attractive, especially in the preparation of sustainable polymeric materials. In this contribution, a terpolymer of CO₂, 1,3-butadiene (BD) and epoxide is synthesized by scandium triflate catalyzed cationic ring-opening copolymerization of α-ethylidene-δ-vinyl-δ-valerolactone (EVL), an intermediate derived from CO₂ and BD, with epoxides. The obtained terpolymer with a CO₂ content of 22 mol% has a number-average molecular weight (M _n) up to 7.8 kg/mol and a dispersity (Đ) of 2.4. The reactivity ratios of EVL and cyclohexene oxide (CHO) are determined as 0.01 and 1.07, respectively, suggesting random characteristic of the terpolymer. The preserved C=C double bonds from BD allow for the further modification of the terpolymer by photoinitiated crosslinking. The yielded networks are fluorescent and degradable. This method offers enhanced versatility to the synthesis and additional functionalization of CO₂-based polymers.