Bifunctional imidodiphosphoric acid-catalyzed controlled/living ring-opening polymerization of trimethylene carbonate resulting block, α,ω-dihydroxy telechelic, and star-shaped polycarbonates

Overview: Polycarbonates via Ring-Opening Polymerization, Differences between Six- and Five-Membered Cyclic Carbonates: Inspiration for Green Alternatives

This review aims to cover the topic of polycarbonate synthesis via ring-opening polymerization (ROP) of cyclic carbonates. We report a wide variety of ROP-initiating systems along with their detailed mechanisms. We focus on the challenges of preparing the polymers; the precise control of the properties of the materials, including molecular weight; the compositions of the copolymers and their structural characteristics. There is no one approach that works for all scales in cyclic carbonates ROP. A green process to produce polycarbonates is a luring challenge in terms of CO₂ utilization and the targeted domains for application. The main resolution seems to be the use of controlled incorporation of functional/reactive groups into polymer chains that can tailor the physicochemical and biological properties of the polymer matrices, producing what appears to be an unlimited field of applications. Glycerol carbonate (GC) is prepared from renewable glycerol and considered as a CO₂ fixation agent resulting in GC compound. This family of five-membered cyclic carbonates has attracted the attention of researchers as potential monomers for the synthesis of polycarbonates (PCs). This cyclic carbonate group presents a strong alternative to Bisphenol A (BPA), which is used mainly as a monomer for the production of polycarbonate and a precursor of epoxy resins. As of December 2016, BPA is listed as a substance of very high concern (SVHC) under the REACH regulation. In 2006, Mouloungui et al. reported the synthesis and oligomerization of GCs. The importance of GCs goes beyond their carbonate ring and their physical properties (high boiling point, high flash point, low volatility, high electrical conductivity) because they also contain a hydroxyl group. The latter offers the possibility of producing oligo and/or polycarbonate compounds that have hydroxyl groups that can potentially lead to different reaction mechanisms and the production of new classes of polycarbonates with a wide range of applications.

Ring-opening polymerization of trimethylene carbonate to poly(trimethylene carbonate) diol over a heterogeneous high-temperature calcined CeO2 catalyst

CeO₂ calcined at 1273 K was an effective reusable heterogeneous catalyst for the synthesis of poly(trimethylene carbonate) diol by ring-opening polymerization of trimethylene carbonate under neat conditions without any additives.

Squaramide and amine binary H-bond organocatalysis in polymerizations of cyclic carbonates, lactones, and lactides

Multiple combinations of six squaramides and eight amines as co-catalysts were success in ROPs of cyclic monomers by H-bond donor and acceptor binary catalysis that established a general protocol.

Tripodal hydrogen bond donor binding with sulfonic acid enables ring-opening polymerization

The first Brønsted acidic catalysis platform workable in all of the three major types of cyclic ester monomers including lactides, cyclic carbonates, and lactones, is described in this paper.

Polymerization of trimethylene carbonates using organic phosphoric acids

1,1′-Binaphthyl-2,2′-diyl hydrogen phosphate (BNPH) catalyzed a controlled/living ROP of TMC through a bifunctional activation mechanism, leading to end-functionalized PTMC and block polymers.

A squaramide and tertiary amine: an excellent hydrogen-bonding pair organocatalyst for living polymerization

A hydrogen-bond motif based on a squaramide and sparteine efficiently promoted the ring-opening polymerization of l-lactide at ambient temperature.

Organophosphate-catalyzed bulk ring-opening polymerization as an environmentally benign route leading to block copolyesters, end-functionalized polyesters, and polyester-based polyurethane

To expand the potential of an organophosphate catalyst, ring-opening polymerization of cyclic esters, cyclic ester-ether, and cyclic carbonate was demonstrated under bulk conditions.

o-Benzenedisulfonimide as a recyclable cationic organocatalyst for the controlled/living ring-opening polymerization of δ-valerolactone and ε-caprolactone

A safe, recyclable, and water-tolerant Brønsted acid o-benzenedisulfonimide (OBS) catalyzed ROP of lactones in a living/controlled manner.

2,4-Dinitrobenzenesulfonic acid in an efficient Brønsted acid-catalyzed controlled/living ring-opening polymerization of ε-caprolactone

2,4-Dinitrobenzenesulfonic acid as an efficient Brønsted acidic catalyst has been evaluated for the controlled/living ring-opening polymerization of ε-caprolactone end-functionalized, α,ω-dihydroxy telechelic poly(ε-caprolactone), and diblock copolymers were also synthesised successfully.