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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 (Mn) 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. [ABSTRACT FROM AUTHOR]

2-Methyltetrahydrofuran (2-MeTHF) is a biomass-based tetrahydrofuran derivative that is considerably difficult to polymerise. This contribution reports Sc(OTf)3-catalysed cationic ring-opening copolymerization of 2-MeTHF with β-butyrolactone (BBL), another renewable monomer. The possibility of copolymerization is verified by density functional theory (DFT) calculations. The obtained copolymer poly(2-MeTHF-co-BBL) has a number-average molecular weight (Mn) of 5.2 kg mol−1, in which the 2-MeTHF content is 48.8 mol% in accordance with the initial feed ratio of 50 mol%. The copolymers have been characterized by NMR, SEC, MALDI-TOF MS and DSC measurements. The cationic ring-opening polymerisation mechanism is confirmed by kinetic studies and DFT calculations. Poly(2-MeTHF-co-BBL) is able to degrade completely within 24 h under alkaline conditions, and has potential as an environmentally friendly material from biomass sources. [ABSTRACT FROM AUTHOR]

It is significant and challenging to use CO2 to produce polymeric materials, especially with olefins. Here, a novel strategy named "scrambling polymerizations" is designed and performed for the copolymerization of a CO2‐and‐1,3‐butadiene‐derived valerolactone, 3‐ethylidene‐6‐vinyltetrahydro‐2H‐pyran‐2‐one (EVL), with ϵ‐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 CO2 and olefins for the first time, and expand the potential of transformation from sustainable feedstocks to polymeric materials. [ABSTRACT FROM AUTHOR]

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% CO2 content and weight‐average molecular weight (Mw) 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‐PEG750 with Mw 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 one‐pot orthogonal strategy is a new utilization of EVL in synthetic polymers and it is significant to the carbon dioxide transformation. [ABSTRACT FROM AUTHOR]