Carbon dioxide/epoxide copolymerization is an efficient way to add value to waste CO2 and to reduce pollution in polymer manufacturing. Using this process to make low molar mass polycarbonate polyols is a commercially relevant route to new thermosets and polyurethanes. In contrast, high molar mass polycarbonates, produced from CO2, generally under-deliver in terms of properties, and one of the most widely investigated, poly­(cyclohexene carbonate), is limited by its low elongation at break and high brittleness. Here, a new catalytic polymerization process is reported that selectively and efficiently yields degradable ABA-block polymers, incorporating 6–23 wt % CO2. The polymers are synthesized using a new, highly active organometallic heterodinuclear Zn­(II)/Mg­(II) catalyst applied in a one-pot procedure together with biobased ε-decalactone, cyclohexene oxide, and carbon dioxide to make a series of poly­(cyclohexene carbonate-b-decalactone-b-cyclohexene carbonate) [PCHC-PDL-PCHC]. The process is highly selective (CO2 selectivity >99% of theoretical value), allows for high monomer conversions (>90%), and yields polymers with predictable compositions, molar mass (from 38–71 kg mol–1), and forms dihydroxyl telechelic chains. These new materials improve upon the properties of poly­(cyclohexene carbonate) and, specifically, they show good thermal stability (T d,5 ∼ 280 °C), high toughness (112 MJ m–3), and very high elongation at break (>900%). Materials properties are improved by precisely controlling both the quantity and location of carbon dioxide in the polymer chain. Preliminary studies show that polymers are stable in aqueous environments at room temperature over months, but they are rapidly degraded upon gentle heating in an acidic environment (60 °C, toluene, p-toluene sulfonic acid). The process is likely generally applicable to many other lactones, lactides, anhydrides, epoxides, and heterocumulenes and sets the scene for a host of new applications for CO2-derived polymers.

Renewable, biodegradable polymers, such as aliphatic polyesters, based on sustainable sources have attracted considerable interest as alternatives to petroleum based polymers. One limiting factor in the development of aliphatic polyesters as replacements for these materials has been their relatively low glass transition temperatures (T g). For example, commercially available poly(lactic acid) has a T g of approximately 60 °C. Epoxide/anhydride copolymerizations offer an alternative to the ring-opening polymerization of lactones for the synthesis of aliphatic polyesters, and allow for tuning of polymer properties through two distinct

A new series of block polyester thermoplastic elastomers are prepared by a one-pot procedure; they show properties competitive or better than conventional materials and can be fully degraded after use.

The formation of bio-derived materials is gaining momentum in academic and industrial laboratories, though the use of terpene oxides as renewable monomers for the preparation of bio-based polymers yet remains limited. In order to advance the impact of such monomers, we have investigated the use of terpene derived epoxides (limonene oxide, carene oxide, limonene dioxide and menthene oxide) for the ring-opening copolymerization (ROCOP) in the presence of various aromatic anhydrides. These copolymerization reactions were mostly performed under mild reaction conditions (65ºC, low loading of catalyst: 0.50 mol%) using a binary catalyst comprising of a Fe(III) based aminotriphenolate complex and PPNCl (bis(triphenylphosphine)iminium chloride) providing partially bio-based semi-aromatic polyesters with molecular weights of up to 25 Kg/mol (Ð = 1.54) and glass transitions spanning a wide range from 59 to 243 ºC. The copolymerization reactions proceed with excellent selectivity towards fully alternating polyesters ( 98% ester bonds) with modular thermal properties that depend on the nature of the terpene oxide used, and are potentially useful towards the development of new coating and thermoset materials.