It is significant and challenging to use CO 2 to produce polymeric materials, especially with olefins. Here, a novel strategy named "scrambling polymerizations" is designed and performed for the copolymerization of a CO 2 -and-1,3-butadiene-derived valerolactone, 3-ethylidene-6-vinyltetrahydro-2H-pyran-2-one (EVL), with ɛ-caprolactone (CL) to prepare polyesters. Anionic ring-opening polymerization of CL and conjugated addition oligomerization of EVL take place individually to form PCL and EVL oligomers, respectively. Then EVL oligomers insert into PCL by transesterification resulting in polyester P(CL-co-EVL) with a tunable topology and composition. The non-cytotoxic and degradable polyester network with elongation at break of > 600 % can be used as an elastomer. We propose a method to provide polyester elastomers from CO 2 and olefins for the first time, and expand the potential of transformation from sustainable feedstocks to polymeric materials.

No abstract

No abstract

As a substituted-δ-valerolactone, α-ethylidene-δ-vinyl-δ-valerolactone (EVL) provides a method of utilizing carbon dioxide with 1,3-butadiene to produce functional polymers. Its di-enesubstituted lactone ring was considered inactive in polymerization in the past two decades, while successful polymerization attempts of EVL have been reported very recently. Novel synthetic strategies and functional polymers from EVL have been developed. The ring-opening reactions of EVL and the corresponding polymers as well as the ring-opening (co)polymerizations of EVL and its derivatives are highlighted in this review. The obtained functional polymers with or without facile post-polymerization modification possess unique properties, such as amphipathy, elasticity, peel resistance, etc., allowing for application potential in various fields.

Being a disubstituted δ-valerolactone synthesized by the telomerization of carbon dioxide with 1,3-butadiene, 3-ethylidene-6-vinyltetrahydro-2H-pyran-2-one (EVL) contains a six-membered ring and two unsaturated groups. This report describes the synthesis of an amphiphilic graft copolymer by the combination of thiol-ene click polymerization and ring-opening grafting reaction of EVL, ethyldithiol (EDT), and methoxy polyethylene glycol (mPEG-OH). The alternating copolymer of P(EVL-alt-EDT) with 17.9 wt% CO 2 content and weight-average molecular weight (M w ) of 7 kg/mol was prepared by means of the free radical thiol-ene click polymerization of EVL with EDT initiated by 2,2-dimethoxy-1,2-diphenylethanone under UV irradiation. The following alcoholysis of the lactone ring of P(EVL-alt-EDT) backbone by mPEG-OH is catalyzed by 1,5,7-triazabicyclo[4.4.0]dec-5-ene, producing the amphiphilic graft copolymer P(EVL-alt-EDT)-g-PEG 750 with M w of 12 kg/mol. The polymers are characterized by nuclear magnetic resonance, Fourier transform infrared, matrix-assisted laser desorption ionization-time of flight mass spectra, size exclusion chromatography and differential scanning calorimetry. The onepot orthogonal strategy is a new utilization of EVL in synthetic polymers and it is significant to the carbon dioxide transformation.